According to the mechanical property requirements of fan impeller welded joints to high-performance welding electrode and combination with principles of welding material designed to microstructure matching, a kind of welding electrode with good mechanical and processing properties was developed by using metallurgical analysis, mechanical property testing and fracture observation.The results show that the deposited metal of developed welding electrode with the alloy system Cr-Ni-Nb-Cu-Ti and mechanical properties of welding electrode developed is superior to the special welding electrode of
FV520(B) stainless steel. Mechanical properties of deposited metal were improved by carbides
rich of chromium and alloying.The carbides are Mo2C3,NbCrN and Ti(C,N) which
are composed by alloy element of Mo,Nb,Ti,Cr and so all.The welding zone and HAZ microstructure of FV520(B) stainless steel is composed of tempered sorbite, lath martensite,
residual austenite and quadratic precipitated phase. However, the fracture mechanism of No.1,No.2 and No.4 welding electrode is quasi-cleavage crack and the No.3 is complex fracture consisting of dimple and cleavage fracture.
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