تاثير زمان و دما در عمليات سرد كردن زير صفر بر رفتار سايشي فولاد 1/2436

The Effect of Cryogenic Treatment on the Wear Behavior of 1.2436 Tool Steel

In this study effects of cryogenic treatment on wear, hardness and mechanical properties of 1.2436 tool steel were studied. For this purpose two temperatures were used, -63 °C as shallow cryogenic temperature and -185 °C as deep cryogenic temperature. In this study effect of cryogenic temperature (Shallow and deep), cryogenic time (holding at cryogenic temperature for 20 and 40 hours), stabilization (holding at room temperature for 1 week) and effect of austenizing temperature (grain size) on wear behavior, hardness and mechanical properties of 1.2436 was studied. Wear test was performed using pin on disk method. IN this respect, 2 different loads 120 and 180 N and 3 different velocities 0.05, 0.1 and 0.2 m/s were examined. It was shown that cryogenic treatment decreases retain austenite and hence improves wear resistance and hardness. This improvement in deep cryogenic treatment is more compare with shallow cryogenic treatment. This could be due elimination of retained austenite as well as better carbide distribution. In longer holding times at cryogenic temperatures, more retain austenite was transformed to martensite and hence better wear behavior and more hardness was seen. By stabilizing at room temperatures more retain austenite was transform to martensite and better wear behavior and more hardness was reached.. Cryogenic treatment increases strength and decrease elongation in this steel, on the other hand, cryogenic treatment decreased toughness. In longer holding time at cryogenic temperatures toughness decrease as a result of retain austenite decrease. Stabilization time at room temperatures decrease toughness as a result of retain austenite decrease.