Strength characterization and microstructure of untreated and cryo treated CrMoV low alloy steel

This study examines the impact of various cryogenic treatments compared to traditional vacuum heat treatment on the development of mechanical characteristics and microstructure of CrMoV Steel. The mechanical characteristics of the samples were analysed to determine the impact of untreated and cryogenically treated materials on hardness, toughness, tensile strength, and microstructure. Experimental evidence showed that the cryogenically treated samples exhibited improved mechanical characteristics compared to the traditionally treated ones. The findings indicated that specimens subjected to cryogenic treatment at a temperature of -100°C for a soaking period of 2 hours, followed by furnace tempering at 200°C for 2 hours, exhibited an 81% increase in tensile strength, an 18% increase in hardness, and a 123% increase in toughness. The confirmation of numerous phases and complicated carbides was achieved using X-ray diffraction, while the shape of microstructure and cracked surfaces was examined using field emission scanning electron microscopy methods.