作　　者： ; ; ; ; ;

机构地区： 中南大学材料科学与工程学院

出　　处： 《金属学报》 2006年第6期629-634,共6页

摘　　要： 在Gleeble-1500热模拟机上对Ni76Crl9AlTi合金棒材进行恒温和恒速压缩变形实验,变形温度范围为800- 1150℃,应变速率范围为10-3-100s-1．结果表明,实验合金在800和850℃热压缩时变形抗力较大,容易发生开裂;而在950-1150℃温度范围内热变形由于发生动态再结晶,合金变形抗力减小,变形容易进行,不会发生开裂．研究了合金在高温塑性变形过程中流变应力的变化规律,确定了合金在950-1150℃范围内的变形激活能Q为376．84 kJ／mol,应力指数n为 4．15．对合金的热压缩变形真应力-真应变曲线及变形机制的分析表明,合理的变形条件为1050-1150℃及10-1-100s-1． The hot deformation behavior of Ni76Cr19AlTi alloy was studied by compression test of cylindrical specimen at constant temperature and constant strain rate in a Gleeble-1500 system. The deformation temperature ranges from 800 ℃ to 1150 ℃, strain rate from 10^-3 s^-1 to 1 s^-1. The results show that Ni76Cr19AlTi alloy has a large deformed resistance and is easily fractured when deformed at 800 ℃ and 850 ℃. But when compressing at a temperature range of 950-1150℃, the resistance to deformation reduces and the alloy doesn＇t fracture because of dynamic crystallization. The measurement of the flow stress of the alloy in high temperature range of 950-1150℃ showed that the thermal deformation activation energy Q is 376.84 kJ/mol and stress exponent n is 4.15. By analyzing the true stress-strain curves for the alloy at hot compression and its deformation mechanism, the suitable deformation condition is at the temperature range from 1050℃ to 1150 ℃ with strain rate from 10^-1 s^-1 to 10^0 s^-1.

关 键 词： 合金 排气门 热压缩变形 热变形激活能

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]