Microstructure and wear resistance of Fe-Cr-C-B-N hardfacing alloy

On the surface of low carbon steel, the Fe-Cr-C-B-N alloy with different nitrogen content was prepared by the method of arc surfacing. The microstructure and properties of the surfacing layer were analyzed by means of X ray diffraction (XRD), optical microscope (OM), scanning electron microscopy (SEM), Rockwell hardness tester and wet sand wear tester. The results show that the microstructure of the surfacing layer is martensite+austenite+BN+M23 (C, B) 6+M3 (C, B)+M2B. With the increase of the amount of nitrogen, the BN was formed in the tissue, the primary austenite was transformed into acicular martensite, and the number of eutectic structure decreased. The hardness of the hardfacing layer increases, and the wear rate decreases firstly and then increases.When the nitrogen content in the surfacing layer is 0.17%, the matrix structure and the hard phase match well, the overall performance of the surfacing layer is the best, the hardness value is 62.7 HRC, and the wear amount is only 0.054 2g.