تاثیر عملیات حرارتی بر روی خواص مکانیکی و بالستیکی فولاد AISI 4140

The heat treatment process was known as one of the most economical routes for development of the high strength steels. Low alloy AISI4140 steel was also famous for its widespread applications in the automotive and aerospace industries. Thus, a combination of heat treatment procedure and using this type of steel could be the economical and applicable process for various industries. As a result, in the current study, the effect of different heat treatment cycles on the yield and ultimate tensile strength and also elongation per cent of the low alloy AISI 4140 was conducted. All of the samples were heat-treated at 880 ˚C for 30 min to achieve Austenite and then quenched in a diesel fuel environment. To continue, by performing the heat treatment cycles at different conditions for each sample, the martensite, martensite-ferrite, and bainite phases were formed.By performing tensile and hardness tests on each of the samples, the mechanical properties, and with the penetration of 7.62 mm projectile of G3 gun, the ballistic properties of the samples were evaluated.