COMPARISON OF MECHANICAL PROPERTIES OF DUAL PHASE STEEL FOR DIFFERENT QUENCHING MEDIUMS

The objective of this study is to find out the best suitable quenching medium for quenching which effects most on the mechanical properties of medium carbon steel. Specimens were first heated in the Muffle Furnace at three different temperatures (i.e., 760 ºC, 800 ºC & 840 ºC) for holding time of 2, 4 and 6 minutes and then quenched in different quenching medium of (water, air and oil). Dual phase steel which is developed from medium carbon steel after heating were examined to record toughness and hardness of the specimens. The mechanical properties of medium carbon steel untreated specimen were also recorded to compare with treated samples of medium carbon steel. The Rockwell hardness test and Charpy test is used to determine the mechanical properties such as hardness & Toughness of both treated and untreated samples of medium carbon steel. The result indicates that the specimen hardness and toughness are proportional to amount of martensite and amount of martensite depends on intercritical annealing temperature. The hardness of the quenched materials is higher than the parent material. The hardness of the water quenched materials is higher than the other quenched materials. The water quenched material had more hardness & toughness as compared to oil & air, to suggest in improved mechanical properties.