Weld Mold 4061 description: Weld Mold 4061 is for welding 200 and 201 nickels. 4061 is also used for welding cast iron and build-up on steels. This product will also join many dissimilar combinations such as high nickels to stainless steels, inconel, carbon steels and incoloy alloys, monel and copper-nickel alloys. Remove old welds, cracks, fatigued metal and base materials from surface. Pre-heat is not required except when welding alloy steels. Multi-layer build-ups are acceptable.