Influence of Age Hardening on Hardness and Wear Properties of Al-Si-Mg (A357) Alloy

摘要

Need of Automotives & Aircraft industries to produce components of complex geometry lead to an increased exploitation of Al-Si-Mg cast alloys. Which possesses excellent castability and good tensile properties &corrosion resistance. For substantial improvement in properties, solutionization and age hardening were carried out. The effect of different artificial aging heat treatment on the properties of A357 alloy cast ingot specimens was evaluated. The experiments include solutionization temperature at 540°C for 8 hrs and artificial aging of the specimens at 155°C for various aging times. The dependencies of hardness and wear properties of the aged alloys on the aging conditions are derived. The investigation involved the effects of load and sliding speed on wear rate and mechanisms during dry sliding. The wear behavior of A357 alloys was influenced by the morphology of silicon particles and the stability of the mechanically mixed layer (MML). In the present investigation Solutionization of Al-7.0Si-0.6 Mg (A357) ALLOY was carried out at 540°C for 8 hrs and rapidly quenched to room temperature in water maintained at 60°C and then age hardened at 155°C for various time periods. The effect of age hardening time on Hardness and wear properties were studied by conducting BRINNEL and PIN-ON-DISK Wear tests. From the above analysis it was revealed that Solutionization and age hardening improve the Hardness and wear resistance of the alloy. This beneficial effect of enhanced wear resistance was more apparent with increase age hardening time.