Quench sensitivity of 2024, 6063 and 7075

Abstract

The influence of quenching temperature during solution heat treatment of 2024, 6063 and 7075 was investigated by means of tensile testing. SEM analyses were carried out on the fracture surfaces. In addition, reduced pressure tests were carried out to correlate the mechanical test results with metal quality. The alloys were received as extruded. SIMA process was applied to achieve spherical grain structure. T6-solution heat treatment was carried out and quenching was done in temperature controlled water bath. Two different quenching temperatures were selected: 20°C and 80°C. The results were analysed by Weibull statistics. It was found that Weibull modules of all test results were similar for all the alloys and there was a good correlation between bifilm index. Ultimate tensile strengths were high when samples were quenched at 20°C. On the other hand, elongations at fracture were high for the samples quenched at 80°C.