Welding Wire

ER420

ER420 is copper-coated high-carbon 13Cr martensitic stainless steel solid wire, suitable for GMAW (MIG/MAG) and GTAW (TIG) welding.

ER420

ER420 is copper-coated high-carbon 13Cr martensitic stainless steel solid wire, suitable for GMAW (MIG/MAG) and GTAW (TIG) welding.

Features

• Higher carbon content delivers high hardness after heat treatment, excellent wear resistance

• Good corrosion resistance to weak acid & atmospheric environment

• Stable arc, compact weld bead for tool & mold repair overlay

• Continuous service temperature: ≤450°C

MIG：0.8 / 1.0 / 1.2 / 1.6 mm 1KG Spool/5KG Spool / 15KG Spool

TIG：2.0 / 2.4 / 3.2 mm /4.0mm 5kg plastic tube

Polarity: DC+ (DCRP, Direct Current Reverse Polarity)

MIG / MAG

Shielding Gas: 98%Ar + 2%O₂ Gas Flow Rate: 20～25 L/min Reference Current for common sizes: Φ0.8mm：70–140 A Φ1.0mm：90–180 A Φ1.2mm：130–200 A

TIG (GTAW)

Shielding Gas: 99.99% High Purity Argon Gas Flow Rate: 8–14 L/min. Back purging is recommended for thick plates.

Base Metal Matching

Suitable for 420 martensitic stainless steel, cutting tools, mold steel repair overlay.

Kitchen cutlery, surgical instruments, plastic molds, wear-resistant roller overlay, shear blade repair.

⚠️ Not for low-temperature impact components; poor toughness without post-heat treatment

Welding Precautions

• Thoroughly remove oil, rust, scale and moisture from grooves before welding to avoid porosity.

• Mandatory preheat 200–400°C; strictly control low heat input to prevent cold cracks.

• Post-weld full tempering is necessary to reduce weld brittleness.

• Wind protection required for outdoor welding over 1.0m/s wind speed.

ER420 vs ER430

✅ ER420 (martensitic high carbon): High hardness, wear-resistant tools & mold overlay

✅ ER430 (ferritic 17Cr): Decorative, nitric acid equipment, low-stress anti-rust parts

Important Cautions

• Pure CO₂ gas is forbidden; extra carbon will cause severe weld cracking risk.

• Not applicable for long-term service in chloride-containing media.