Microstructural Evolution and Softening Behavior of Simulated Heat-Affected Zone in 2219 Aluminum Alloy

• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2017,（12）
• 页码范围: 1177-1184
• 页数: 8页
• 语种: 英文
• DOI: 10.1007/s40195-017-0586-3

摘要

0The effect of peak temperature (Tp) at 200,300,400,500 and 550 ℃ on the microstructural evolution and softening behavior of the simulated heat-affected zone (HAZ) was studied in the 2219-T87 alloy by electron-backscatter diffraction,transmission electron microscopy,X-ray diffraction,micro-hardness and micro-tensile tests.The results showed that the grain size in the HAZs at 200-500 ℃ was comparable,but the number density of the strengthening precipitates (GP zones/θ') decreased with increasing Tp.At a Tp of 550 ℃,the grain size significantly decreased and the distribution of the misorientation angles corresponded to the MacKenzie distribution.The GP zones/θ'phase coarsened and translated into θ phases at Tp values in the range of 200-400 ℃.Increasing the Tp to 500 ℃ and above,some θ'phases translated into θ phases and others dissolved into the α-Al matrix which led to an increase in the solid solution strengthening.The reduction of the number density of the GP zones/θ'was responsible for the softening behavior.