Abstract:
Cr
3C
2/Ni
3Al composite is a potential candidate for elevated temperature surface hardfacing material.The weldability is very important for its application.When the Cr
3C
2-NiAl-Ni welding wires produced by pressureless sintering process in vacuum were welded on the surface of carbon steel and heat resistant steel by the manual gas tungsten arc welding,crack-free Cr
3C
2/Ni
3Al composite coatings were obtained.The Cr
3C
2/Ni
3Al composite possesses good weldability and is suitable for industry application as hardfacing material of iron base material.The good weldability is attributed to following factors:(1) Cr
3C
2 is dissolved during hardfacing.C precedes Al to be oxidized in melting pool thereby protects Al from oxidation severely.(2) Some Fe diffuses into hardfacing metal from steel and Cr that comes from dissolved Cr
3C
2 enters into Ni
3Al matrix,which improves the weldability of Ni
3Al markedly.