Comparison of K340 Steel Microstructure and Mechanical Properties Using Shallow and Deep Cryogenic Treatment

In this research, Böhler K340 cold work tool steel was subjected to three different heat treatment protocols, conventional (CHT), shallow cryogenic (SCT), and deep (DCT). The study compares the effect of SCT DCT on microstructure consequently selected mechanical properties (micro- macroscale hardness impact toughness). shows no significant difference in after treatments. However, microhardness values indicate a slightly lower case DCT. Microstructure analysis with light (LM) scanning electron microscopy (SEM) indicated finer more homogenous smaller lath size preferential orientation martensitic matrix samples compared CHT. addition, uniform precipitation spherical carbides is determined for both Moreover, small dispersed secondary observed DCT, whereas CHT counterparts, these carbide types were not detected. X-ray diffraction (XRD) backscatter (EBSD) confirms that are very effective minimizing amount retained austenite down 1.8 vol.% even below 1 variant.