Effect of Salt quenching on the microstructures and mechanical properties of AISI 1045 steel

Steel has a very important role in the industrial applications, especially for the manufacture of automotive components such as gear. In its applications, gear undergoes the compressive and friction loads, so that in the manufacturing process, materials with high hardness and wear resistance are needed. One method to increase steel hardness is by quenching process. In this research, quenching process will be carried out on AISI 1045 steel using pure water and the salt solution as the cooling medium. The austenization process was conducted at a temperature of 850 degrees C with the holding time of 15 and 30 minutes. The samples were then quenched at the cooling medium of salt solution with concentration of 0, 10 and 23%. The results showed that the quenching process on AISI 1045 steel promotes the phase transformation from mixture of ferrite and pearlite to be martensite. The increase of austenization holding time and salt concentration level resulted in higher martensite intensity and hardness. In contrast, the increase of austenization holding time and salt concentration level resulted in lower toughness.