Microstructure of W18Cr4V High Speed Steel After Cryogenic Treatment

The microstructure of W18Cr4V high speed steel before and after repeated cryogenic treatment was studied using X-ray diffraction and transmission electron microscopy.The results show that in comparison with single long cryogenic treatment after repeated cryogenic treatment,the axial ratio and carbon content of martensite decrease significantly,the residual austenite content further lowers,a lot of new ultra-fine dispersed carbide particles precipitates on the twin bands and dislocation lines of martensite,therefore,the effect of repeated cryogenic treatment is better than that of the single long cryogenic treatment for high speed steel.