Investigation of the effect of heat treatment and shot peeni̇ng on AlSi10Mg alloy produced by additive manufacturing method

AlSi10Mg alloy formed by selective laser melting (SLM), one of the additive manufacturing methods, often requires secondary treatments to rule out disadvantages such as surface roughness, stress accumulation and internal defects. In this study, the effects of T6 heat treatment (HT) as well as ball forging (VP) at different temperatures and for different times were applied to AlSi10Mg alloy, and both single and multiple effects of these treatments were investigated. AlSi10Mg alloys were heat treated with no heat treatment and solution treatment temperatures of 400 °C, 450 °C, 500 °C, respectively. Vibratory peening (VP) was applied for 2.5 min, 5 min, 10 min and 20 min at the applied heat treatment temperatures. The changes in microstructure, hardness and wear properties of untreated (AB), vibration peening (AB+VP), heat treated (AB+HT) and vibration peening/heat treated (AB+HT+VP) specimens were investigated. While there was a single-phase microstructure after SLM, Si precipitates were formed in the structure with the heat treatment applied and a two-phase microstructure was formed. The size of Si precipitates in the new phase increased as the dissolution temperature increased. The hardness of the surfaces was improved by the vibratory forging process and the increase in VP time increased the depth of impact on the surface. Increasing the solution temperature led to an improvement in hardness. Although the hardness of the AlSi10Mg alloy produced by selective laser melting was significantly reduced by heat treatment (HT), the hardness was increased by vibration forging. Since vibratory forging leads to increased wear resistance, these hardness values increased slightly with increasing solution temperatures and wear losses were significantly reduced.