Weldability is an essential part of welding technology. Process , material and service weldability need to be established for any given application. Welding metallurgy pertaining to metals and alloys requires understanding. Metallurgical and mechanical behavior analysis forms the basis for performance evaluation of any engineering structure or component. Defects , sizing and acceptance criteria requires using of appropriate NDT methods. Fracture toughness studies to make fail safe designs are now mandatory for nuclear and defence applications. Cold cracking and hot cracking behavior , low and high temperature behavior of welded joints requires special attention.

The effect of gases (Hydrogen , oxygen and nitrogen) on weld metal properties has to be analyzed critically for evaluating service behavior.