Cryogenic Treatments of Hot Work Tool Steel (56NiCrMoV7)


The main objective of this paper is to study the effect of Cryogenictreatment of hot work tool steel type (56NiCrMoV7) on the microstructure andmechanical properties. Three different temperature (-50°C,-100°C & -150°C)were selected at different soaking time(1hr,2hr & 3hr) respectively. All cryogenictreatments were adopted after hardening by air & oil respectively. It wasconcluded that the property enhancement for this tool steel can be attributed byconversion most of retained austenite to martensite accompanied with higherdislocations density that leads to the precipitation of fine carbide during thecryogenic treatment especially at the samples quenched by oil & treated at (-150°C) with soaking 1hr