(1. 西北有色金属研究院 钛合金研究所，西安 710016；
2. 西北工业大学 材料学院，西安 710072)
摘 要: 对等轴组织TC21合金进行β相区高温固溶+α/β相区低温固溶+低温时效热处理；分析β相区高温固溶冷却速率、α/β相区低温固溶温度对TC21合金组织和性能的影响。结果表明：随着β相区固溶冷却速率的增加，α/β相区固溶热处理后合金中条状α相尺寸明显减小，α条厚度减小；随着α/β区固溶处理温度的降低，在相同的β相区固溶冷却速率下，合金中的初生条状初生α相尺寸有一定的减小，相含量增加。经过(960 °C, 1 h, FC)+ (890 °C, 1 h, AC)+(620 °C, 6 h, AC)三重热处理后，TC21合金的强度、塑性和韧性匹配较好。这表明三重热处理可以改善常规锻造TC21合金的综合力学性能。
关键字: β固溶处理；TC21合金；冷却速率；强韧性匹配
（1. Titanium Alloy Research Center, Northwest Institute for Non-ferrous Metal Research, Xi’an 710016, China;
2. School of Materials Science and Engineering, Northwest Polytechnical University, Xi’an 710072, China）
Abstract:The equiaxed TC21 alloy samples were β solution treated, followed by α/β solution treatment and then aged at low temperature. The effect of β heat treatment cooling rate and temperature of α/β heat treatment on the morphology of TC21 alloy was analyzed. The results show that higher cooling rate of β heat treatment leads to the shrinking of platelet α phase, in the α/β heat treatment process. It is also confirmed that lower α/β heat treatment temperature, after the same beta heat treatment process, results in the decrease of width and increase of the content of platelet α phase. After optimized triplex heat treatment (960 °C, 1 h, FC)+(890 °C, 1 h, AC)+(620 °C, 6 h, AC), the strength, plasticity and fracture toughness match well, indicating that the triplex heat treatment can improve the synthetical mechanical properties of TC21 alloy.
Key words: β solution treatment; TC21 alloy; cooling rate; matching of strength and fracture toughness
