Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
TIG Welding (GTAW): Precision and Quality
Gas Tungsten Arc Welding (GTAW) uses a non-consumable tungsten electrode with a separate filler rod. It produces the cleanest, most precise welds but at lower speeds. TIG is essential for applications where weld appearance and integrity are critical.
| Steel Thickness | Tungsten Diameter | Current DCEN (A) | Filler Rod | Gas Flow (L/min) |
|---|---|---|---|---|
| 1–3 mm | 1.6–2.4 mm | 60–120 | ER70S-2 | 8–10 |
| 3–6 mm | 2.4–3.2 mm | 120–200 | ER70S-2/6 | 10–14 |
| 6–10 mm | 3.2–4.0 mm | 200–300 | ER70S-6 | 14–18 |
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
TIG Welding (GTAW): Precision and Quality
Gas Tungsten Arc Welding (GTAW) uses a non-consumable tungsten electrode with a separate filler rod. It produces the cleanest, most precise welds but at lower speeds. TIG is essential for applications where weld appearance and integrity are critical.
| Steel Thickness | Tungsten Diameter | Current DCEN (A) | Filler Rod | Gas Flow (L/min) |
|---|---|---|---|---|
| 1–3 mm | 1.6–2.4 mm | 60–120 | ER70S-2 | 8–10 |
| 3–6 mm | 2.4–3.2 mm | 120–200 | ER70S-2/6 | 10–14 |
| 6–10 mm | 3.2–4.0 mm | 200–300 | ER70S-6 | 14–18 |
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
- Shielding gas: 75% Ar / 25% CO₂ (spray transfer) or 100% CO₂ (short circuit, economical)
- Filler wire: ER70S-6 for low carbon, ER80S-D2 for medium carbon steel
- Transfer mode: Short circuit for thin sheet (<6mm), spray transfer for plates >8mm
- Best for: High-volume fabrication, structural steel, automotive components, shipbuilding
TIG Welding (GTAW): Precision and Quality
Gas Tungsten Arc Welding (GTAW) uses a non-consumable tungsten electrode with a separate filler rod. It produces the cleanest, most precise welds but at lower speeds. TIG is essential for applications where weld appearance and integrity are critical.
| Steel Thickness | Tungsten Diameter | Current DCEN (A) | Filler Rod | Gas Flow (L/min) |
|---|---|---|---|---|
| 1–3 mm | 1.6–2.4 mm | 60–120 | ER70S-2 | 8–10 |
| 3–6 mm | 2.4–3.2 mm | 120–200 | ER70S-2/6 | 10–14 |
| 6–10 mm | 3.2–4.0 mm | 200–300 | ER70S-6 | 14–18 |
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
- Shielding gas: 75% Ar / 25% CO₂ (spray transfer) or 100% CO₂ (short circuit, economical)
- Filler wire: ER70S-6 for low carbon, ER80S-D2 for medium carbon steel
- Transfer mode: Short circuit for thin sheet (<6mm), spray transfer for plates >8mm
- Best for: High-volume fabrication, structural steel, automotive components, shipbuilding
TIG Welding (GTAW): Precision and Quality
Gas Tungsten Arc Welding (GTAW) uses a non-consumable tungsten electrode with a separate filler rod. It produces the cleanest, most precise welds but at lower speeds. TIG is essential for applications where weld appearance and integrity are critical.
| Steel Thickness | Tungsten Diameter | Current DCEN (A) | Filler Rod | Gas Flow (L/min) |
|---|---|---|---|---|
| 1–3 mm | 1.6–2.4 mm | 60–120 | ER70S-2 | 8–10 |
| 3–6 mm | 2.4–3.2 mm | 120–200 | ER70S-2/6 | 10–14 |
| 6–10 mm | 3.2–4.0 mm | 200–300 | ER70S-6 | 14–18 |
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
Carbon Steel Welding Methods: MIG, TIG & Stick Welding Guide
Welding is the most common joining method for carbon steel, accounting for over 70% of all structural fabrication globally. Whether you are manufacturing pressure vessels, building steel structures, or repairing heavy machinery, the choice of welding method directly determines joint quality, production efficiency, and total fabrication cost. This guide covers the three primary arc welding processes—MIG (GMAW), TIG (GTAW), and Stick (SMAW)—with specific parameters and recommendations for low, medium, and high carbon steel grades.
Understanding Carbon Steel Weldability by Carbon Content
The carbon content of steel is the single most important factor determining weldability. The carbon equivalent (CE) formula provides a more accurate prediction of welding behavior by accounting for the combined effect of alloying elements:
CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15
| Category | Carbon % | CE Range | Weldability | Preheat Required |
|---|---|---|---|---|
| Low Carbon | ≤0.25% | <0.40 | Excellent | Usually not |
| Medium Carbon | 0.25–0.55% | 0.40–0.60 | Fair to Good | 150–260°C |
| High Carbon | 0.55–1.00% | >0.60 | Poor | 260–400°C |
Low carbon steels like Q235, S235JR, and ASTM A36 are readily weldable by all three methods without special procedures. Medium carbon steels like SAE 1045, C45, and S45C require preheat and controlled cooling to avoid hydrogen cracking. High carbon steels like 65Mn and C70S demand strict preheat, post-weld heat treatment, and low-hydrogen processes.
MIG Welding (GMAW): Speed and Productivity
Gas Metal Arc Welding (GMAW), commonly called MIG welding, is the workhorse of carbon steel fabrication. A continuously fed wire electrode melts under a shielding gas to form the weld pool. It offers the highest deposition rates of the three methods.
Recommended Parameters for Carbon Steel MIG Welding
| Plate Thickness | Wire Diameter | Voltage (V) | Current (A) | Wire Feed (m/min) | Gas Flow (L/min) |
|---|---|---|---|---|---|
| 3–6 mm | 0.8–1.0 mm | 18–22 | 100–180 | 3–6 | 12–15 |
| 6–12 mm | 1.0–1.2 mm | 22–28 | 180–280 | 6–10 | 15–18 |
| 12–25 mm | 1.2–1.6 mm | 28–32 | 280–400 | 10–16 | 18–22 |
- Shielding gas: 75% Ar / 25% CO₂ (spray transfer) or 100% CO₂ (short circuit, economical)
- Filler wire: ER70S-6 for low carbon, ER80S-D2 for medium carbon steel
- Transfer mode: Short circuit for thin sheet (<6mm), spray transfer for plates >8mm
- Best for: High-volume fabrication, structural steel, automotive components, shipbuilding
TIG Welding (GTAW): Precision and Quality
Gas Tungsten Arc Welding (GTAW) uses a non-consumable tungsten electrode with a separate filler rod. It produces the cleanest, most precise welds but at lower speeds. TIG is essential for applications where weld appearance and integrity are critical.
| Steel Thickness | Tungsten Diameter | Current DCEN (A) | Filler Rod | Gas Flow (L/min) |
|---|---|---|---|---|
| 1–3 mm | 1.6–2.4 mm | 60–120 | ER70S-2 | 8–10 |
| 3–6 mm | 2.4–3.2 mm | 120–200 | ER70S-2/6 | 10–14 |
| 6–10 mm | 3.2–4.0 mm | 200–300 | ER70S-6 | 14–18 |
- Shielding gas: 100% Argon
- Polarity: DCEN (DC Electrode Negative) for carbon steel
- Material prep: Surface must be absolutely clean — remove all rust, scale, oil, and moisture
- Best for: Pressure vessels, pipe welding, food-grade equipment, thin-wall tubing, root passes
Stick Welding (SMAW): Versatile and Field-Ready
Shielded Metal Arc Welding (SMAW) remains indispensable for outdoor and field applications. The flux coating on the electrode generates its own shielding gas, making it wind-resistant and suitable for all positions.
Electrode Selection Guide for Carbon Steel
| Electrode (AWS) | Tensile (KSI) | Coating Type | Position | Application |
|---|---|---|---|---|
| E6010 | 60 | Cellulose sodium | All | Root pass, pipe welding, deep penetration |
| E6013 | 60 | Rutile | All | General purpose, smooth bead, sheet metal |
| E7018 | 70 | Low hydrogen iron powder | All | Structural, medium carbon, crack-resistant |
| E8018-B2 | 80 | Low hydrogen | All | Medium carbon steel, Cr-Mo steels |
- E7018 is the go-to electrode for medium carbon steel welding. Its low-hydrogen coating minimizes the risk of hydrogen-induced cracking.
- Store low-hydrogen electrodes in a rod oven at 120–150°C. Exposed electrodes absorb moisture within 4 hours.
- Best for: Construction sites, pipeline welding, repair work, heavy equipment, structural steel erection
Method Selection: MIG vs TIG vs Stick at a Glance
| Criterion | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) |
|---|---|---|---|
| Deposition Rate | ★★★★★ | ★★☆☆☆ | ★★★☆☆ |
| Weld Quality | ★★★★☆ | ★★★★★ | ★★★★☆ |
| Thin Material (<3mm) | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Outdoor/Wind | ★☆☆☆☆ | ★★☆☆☆ | ★★★★★ |
| Equipment Cost | $$$ | $$$$ | $ |
| Operator Skill | Medium | High | Medium |
| Production Speed | ★★★★★ | ★☆☆☆☆ | ★★★☆☆ |
Preheat and Post-Weld Heat Treatment Requirements
For medium and high carbon steels, preheat and PWHT are non-negotiable:
| Steel Grade | Preheat Temp (°C) | Interpass Max (°C) | PWHT Temp (°C) | PWHT Time |
|---|---|---|---|---|
| Q235/S235JR | Not required | — | Not required | — |
| S355JR/Q345 | 50–100 (t>30mm) | 300 | Not required | — |
| SAE 1045/C45 | 150–260 | 300 | 600–650 | 1 hr/25mm |
| S50C/S55C | 200–300 | 300 | 600–650 | 1 hr/25mm |
| 65Mn/C70S | 260–400 | 250 | 600–680 | 1 hr/25mm |
Pro tip: Always verify preheat temperature with a temperature-indicating crayon (Tempilstik) or infrared thermometer at least 75mm from the joint in all directions. The preheat must be maintained throughout the welding process.
FAQ
Q: Can I MIG weld medium carbon steel without preheat?
A: Not recommended. Without preheat, the rapid cooling rate in the HAZ (Heat Affected Zone) can form hard, brittle martensite, leading to cracking. Always preheat medium carbon steel to at least 150°C.
Q: Which welding method is best for S45C carbon steel?
A: TIG welding with ER70S-6 filler and 200–260°C preheat produces the best results. If TIG is not practical, use E7018 stick electrodes with the same preheat requirement.
Q: What causes porosity in carbon steel MIG welds?
A: The most common causes are insufficient shielding gas flow, wind disrupting the gas shield, contaminated base metal (rust, oil, paint), or moisture in the wire or gas system.
Q: How do I prevent hydrogen cracking in medium carbon steel?
A: Use three strategies together: (1) low-hydrogen consumables (E7018, ER70S-6), (2) proper preheat (150–260°C), and (3) slow cooling after welding (cover with insulating blanket or perform PWHT).
Source Quality Carbon Steel for Welding Fabrication
Huaxia-Steel supplies a full range of weldable carbon steel products — plates, pipes, structural sections, and bars — in grades optimized for your welding process. All products include full MTC documentation with chemical composition verified for weldability. Request a quote today with your specifications.
