BM410NM00001870E60 - E410NiMo 3/16 Inch Martensitic Stainless Stick Electrode

Technical Overview of E410NiMo Electrodes

The Exocor E410NiMo 3/16" Coated Electrode is a premium consumable designed for the Shielded Metal Arc Welding (SMAW) of martensitic stainless steels. This electrode is formulated according to AWS A5.4 specifications, featuring a nominal composition modified from standard E410 by the addition of approximately 4.5% Nickel and 0.5% Molybdenum. The metallurgical objective of these additions is to refine the microstructure of the as-welded deposit, specifically to minimize or eliminate the presence of delta ferrite. Ferrite in martensitic stainless steel welds can lead to reduced notch toughness and ductility; therefore, the E410NiMo chemistry ensures a fully martensitic structure that responds well to post-weld heat treatment (PWHT).

This electrode is specifically engineered for joining and repairing cast materials of similar composition, most notably ASTM A487 Grade CA6NM. These materials are ubiquitous in the power generation industry, particularly within hydroelectric turbines, runners, and wicket gates, where resistance to cavitation, erosion, and corrosion is paramount. The 3/16" diameter allows for higher deposition rates in flat and horizontal positions, making it suitable for heavy-section repairs and fabrication. The weld metal exhibits high tensile strength and excellent impact properties after proper heat treatment.

Preheat and interpass temperature controls are critical when using E410NiMo to prevent cold cracking in the heat-affected zone (HAZ). A preheat of 100°C to 150°C is typically recommended, followed by a post-weld heat treatment in the range of 600°C to 620°C to temper the martensite and restore ductility. This electrode provides a reliable solution for critical infrastructure maintenance where structural integrity and longevity are non-negotiable.