Heat resistant steel and high temperature alloy are widely used in the field of high temperature components. Because the alloy is welded to a very wide. Their composition and welding metallurgy problems are very complex. The complex includes the following contents.
The complex system can be: O alloy iron-based alloy iron-based alloy ", in low and high alloy steels, various types of stainless steel, even with high Cr. Ni alloy elements). Can also be based on Ni or C. A very complex alloy system based on components
The organization structure is complex: Alloy ferrite or pearlite (bainite) organization. Can also be martensite or austenite; can be single organization. It can also be multi phase hybrid organization; from solidification to room temperature for single-phase state. Can also occur with the decrease of temperature and phase transition. Phase transformation product type, quantity and morphology and performance and cooling speed. Because of the difference of composition and temperature, some precipitates may occur in some alloys.