Molybdenum-alloyed welding wire
Molybdenum-alloyed welding wire increases high-temperature strength and creep resistance in pressure vessels. It prevents carbide formation at high temperatures.
Physical-Chemical Mechanism of Action
Molybdenum-alloyed filler wire contains molybdenum atoms that bond with alloying elements in the molten pool. This bonding prevents the formation of carbides that would otherwise precipitate at high temperatures and weaken the material.
Metallurgical Relevance & Welding Risks
Without molybdenum-alloyed wire, carbides can form in pressure vessels at elevated temperatures, reducing hot strength and creep resistance. That can lead to safety issues and distortion in the vessel.
Shop Practice & Action Items
Use molybdenum-alloyed filler wire when making pressure vessels, especially where high temperatures are expected. Follow the melting and cooling procedures closely to get a uniform structure and maximum strength.