Abstract:
52M alloy surfacing layer was deposited on the substrate of S304 stainless steel by laser surfacing and TIG surfacing, respectively, with 52M alloy wire as surfacing material, and then the microstructure, phase composition and sensitivity of high-temperature ductility-dip cracking of the surfacing layers were studied. The results show that the microstructures of the two surfacing layers consisted of uniphase austenite. Compared with those of the TIG surfacing layer, the grain size of the laser surfacing layer was smaller and the grain shape was more regular. Cr
23C
6 was precipitated in the two surfacing layers. The amount of the precipitates in the laser surfacing layer was relatively small. The amount of cracks in the laser surfacing layer was smaller than that in the TIG surfacing layer at the same temperature and different strains. With the increase of strain, the amount of cracks in the laser surfacing layer increased faster, but the sensitivity of ductility-dip cracking was lower.