Effects of Austenized and Forged on Microstructure and Mechanical of MIL A-12560/ AISI 4340 Steel

Laterite steels might be used for alternative armored steels. Their properties can be improved in various ways, such as by heat treatment. This paper reports the influences of tempering temperature on hardness and microstructure of the modified MIL A-12560/ AISI 4340 steels. Samples were austenitized at 1200, 1000 and 800C and forged at 100, 75, 50, and 700 T. Mechanical properties consisted of Hardness measurement was conducted by Brinell indentation and metallographic observation was conducted by scanning electron microscope (SEM). The results show that increasing forging force until 100 T can decreased hardness. The microstructure formed consists of tempered martensite containing ferrite and perlite dual phase. The presence of void and porous can also decreasing hardness. Decreasing austenizing temperature from 1200C to 800C can increase impact strength and hardness material. The International Conference on Advanced Materials Science and Technology 2016