Study on Microstructural Characteristics and Mechanical Behaviour of AISI1050 Steel under Various Heat Treatments

Heat treatment of metal alloys is one of the most widely used techniques for achieving the desired mechanical properties by modifying the microstructure namely the grain and or by altering the second phases present in heat treat able alloys. At times heat treated materials undergo further process like forming, machining, welding etc. Thus the present work describes the effect of heat treatment of AISI 1050 steel and its associated micro structural changes that correlate it with the mechanical behaviour. AISI 1050 steel is widely used in the production of bearings, landing gear, actuators and aerospace structural components. In this study, different samples of AISI 1050 steel were heat treated to temperature above the austenitic region and were subjected to annealing or normalising, or spheroiding. It is indicative that the properties of the AISI 1050 steel can be easily altered by heat treatment to suit a particular application and for secondary processing. The property comparison includes micro structural grain size, yield strength, tensile strength, hardness and percentage elongation. Thus the results provide a better insight on the process of increasing the versatility of the AISI 1050 steel for its demanding use in aerospace structural applications and related mechanical processing. It was found that the effect of heat treatment has resulted in increased grain size, decreased strength and hardness, and improved properties which were more suitable for machining and forming process.