CAJ | 학술논문

通过在700～950℃和应变速率0.001～50s~(-1)条件下的热模拟实验,系统研究了TC18钛合金应变速率、变形温度对变形抗力和显微组织的影响.结果表明:提高变形温度或降低应变速率,可显著降低TC18合金变形过程中的真应力,与单相区相比,两相区变形抗力对温度的变化更为敏感.在α+β区变形时,α相和β相都参与变形,球状初生α沿形变方向略有拉长,β相沿金属流动方向形成纤维组织;β相变点以上温度变形时,β相沿金属流动方向呈纤维状分布,在950℃可以观察到再结晶的等轴β晶粒.
통과재700～950℃화응변속솔0.001～50s~(-1)조건하적열모의실험,계통연구료TC18태합금응변속솔、변형온도대변형항력화현미조직적영향.결과표명:제고변형온도혹강저응변속솔,가현저강저TC18합금변형과정중적진응력,여단상구상비,량상구변형항력대온도적변화경위민감.재α+β구변형시,α상화β상도삼여변형,구상초생α연형변방향략유랍장,β상연금속류동방향형성섬유조직;β상변점이상온도변형시,β상연금속류동방향정섬유상분포,재950℃가이관찰도재결정적등축β정립.
The effect of strain rate and deformation temperature on the deformation resistance and the microstructure of TC18 titanium alloy was studied through heat simulating test at 700-950℃ and strain rate 0.001-50s~(-1) .The results show that, when the deformation temperature increases or the strain rate decreases, the real stress can be reduced obviously. Comparing to deformation in β phase, deformation resistance in α+β phase is more sensitive to the change of temperatures. When α+β phase deformed, α and β phases join in deformation at the same time, but deformation degree is different. Preliminary equiaxed alpha phase is elongated slightly and beta phase changes to fiber texture along deformation direction. When β phase deformed, beta phase is fibrous along metal flowing direction, and equiaxed beta grain can be seen when the deformed temperature is above 950℃.