温度和应变速率对Ti-1023合金等温压缩行为的影响  

Effect of Temperature and Strain Rate on the Isothermal Compression Behavior of Ti-10V-2Fe-3Al

作　　者：郭鸿镇[1] 姚泽坤[1] 冯超[1] 苏祖武[1] 

机构地区：[1]西北工业大学,陕西西安710072

出　　处：《稀有金属材料与工程》2003年第7期566-568,共3页Rare Metal Materials and Engineering

摘　　要：在(α+β)两相区对Ti-1023合金进行等温压缩试验,实测高温流动应力曲线,讨论流动应力及显微组织随温度及应变速率的变化规律,实验结果表明,Ti-1023合金的流动应力对应变速率非常敏感;变形温度对流动应力的影响程度与应变速率大小有关,在ε=1.0s-1的较快速变形时,当温度由760℃提高到800℃时,流动应力值下降约40MPa,而在ε=1.6×10-4s-1的慢速变形时,流动应力值仅下降10MPa;显微组织观察结果表明,在相同温度下较快速变形时(ε=1.0s-1),所得显微组织比较细小、均匀,而慢速变形时(ε=1.6×10-4s-1),初生α相及组织比较粗大,亚β晶界也比较明显。因此,在保证锻件良好成形的前提下,Ti-1023合金在等温锻造时可采用适当大的应变速率。Isothermal compression testing of Ti-10V-2Fe-3Al in (alpha + 8) phase zone was carried out. Hot compression flow stress curves have been determined, and changing laws of flow stress and microstructure versus temperature and strain rate have been discussed in order to provide test basis for determining isothermal forming technological parameters. The results show that flow stress is very sensitive to strain rates. For example, flow stress is 220 MPa for true starting strain rate of 1.0 s(-1) at 760degreesC, and, flow stress is only 40 MPa when strain rate is reduced to 1.6 x 10(-4)s(-1); it is reduced by 5.5 times. The effect of the deformation temperature on flow stress is relative with measure of strain rate. When deformation temperature increases from 760degreesC to 800degreesC, the flow stress decreases by 40 MPa using faster strain rate of 1.0s(-1), and decreases only by 10MPa using slower strain rate of 1.6 x 10(-4)s(-1). The observation results of microstructure show that at same deformation temperature the microstructure of Ti-10V-2Fe-3Al is finer and more uniform using faster strain rate than that of the primary a phase using slow strain rate. Under good forming condition of forgings, strain rate may be appropriately raised during isothermal forging of Ti-10V-2Fe-3Al.

关 键 词：Ti—1023合金 等温压缩 流动应力 显微组织 

分 类 号：TG146.23[一般工业技术—材料科学与工程]