Study on the Effect of Heat Treatment Process on the Dynamic Impact Mechanical Properties of Aluminum Alloys
摘要
This study investigates the influence of various heat treatment processes on the dynamic impact properties of 7075 aluminum alloy. Dynamic compression tests were performed using a Hopkinson pressure bar over a temperature range of 20 °C to 420 °C and strain rates from 1800 to 5800 s−1, followed by an analysis of the alloy’s mechanical behavior under these conditions. The findings show that the yield strength of 7075 aluminum alloy, after undergoing three distinct heat treatment procedures, increases with higher strain rates and decreases as temperature rises, indicating a clear sensitivity to both factors. At ambient temperature, the flow stress of the alloy demonstrates an upward trend across all three heat treatments as the strain rate increases. Specifically, the yield strengths in the T6, T76, and RRA conditions at a strain rate of 5800 s−1 are 1.47, 1.38, and 1.19 times greater than those measured at 1800 s−1, respectively. As the temperature elevates to 420 °C, all three aging conditions reveal pronounced thermal softening, attributed to high-temperature deformation. At elevated strain rates under room temperature conditions, the yield strength follows the order of T76 > T6 > RRA. However, at 420 °C, with the same high strain rates, the order shifts to RRA > T76 > T6.