410

These consumables are specifically designed for welding 12% Cr martensitic stainless steels, such as type 410, in both wrought and cast conditions. It is crucial that fabrication welds, with a similar composition, undergo appropriate post-weld heat treatment (PWHT) due to high hardness (~450 HV) and low ductility in the as-welded condition. Type 410 contains a sufficient amount of carbon to promote transformation through air hardening into a primarily martensitic microstructure. Structural performance below room temperature is limited by the relatively high ductile-brittle transition temperature (especially in welds) and modest creep resistance up to about 550 °C. It has good general corrosion resistance in non-aggressive environments, sulfide stress corrosion cracking resistance in sour crude oil conditions, and oxidation resistance up to about 800 °C. Typical applications include hydrocrackers, reaction vessels, distillation units, and associated piping in refineries; furnace components, linings; cladding for pinch rolls in steel mills; cast valve bodies, turbine parts, and burner nozzles.

12%Cr (410) martensitic stainless steel.

In the PWHT condition the microstructure consists of tempered martensite with some retained ferrite.

• EN W.Nr.: 1.4006 (X10Cr13), 1.4006 (G-X10Cr13), 1.4000 (X6Cr13), 1.4024 (X15Cr13)
• ASTM: 410, 410S, 403, A487 gr. CA15
• UNS: S41008, S40300

For thicker sections, preheating to a temperature between 150 and 250 °C is essential. After welding, components should be allowed to cool to room temperature before PWHT. Weld metal and heat-affected zones (HAZ) exhibit poor ductility and toughness in the as-welded condition; therefore, careful handling is advised prior to PWHT to minimize any physical impacts. A typical industrial PWHT for unalloyed 410 involves slow cooling to room temperature to ensure complete transformation (range: MS-350 °C, MF-100 °C), followed by tempering at 680-760 °C and subsequent air cooling. To ensure a hardness below 22 HRC (per NACE) in the weld area, a PWHT at 745 °C is preferred.