摘要
用示差扫描量热仪和拉伸试验对比研究了Ti-50.8Ni、Ti-49.8Ni-1.0Co、Ti-50.8Ni-0.5V和Ti-50.8Ni-0.3Cr(原子分数%)超弹性合金的相变和形变特性。结果表明,冷却加热时,400℃退火态Ti-50.8Ni-0.3Cr合金发生AR(A-母相,R-R相)一阶段可逆相变,其余3合金发生ARM(M-马氏体)两阶段可逆相变。以Co取代Ni,以Cr、V取代Ti后,Ti-Ni合金的R、M相变温度和相变热降低,M相变热滞增加,R相变热滞变化不大。4种合金室温下皆显示超弹性,加入1.0%Co和0.5%V后,合金的超弹性应力分别减小了130MPa和85MPa,超弹性应变分别减小了1.8和2.4;加入0.3%Cr后,合金的超弹性应力增加了147MPa,超弹性应变减小了2.9;Co、Cr、V的加入使合金的应力-应变回线面积减小。
Abstract： The transformation and deformation characteristics of Ti-50. 8Ni,Ti-49.8Ni-1.0Co,Ti-50. 8Ni-0. 5V and Ti- 50. 8Ni-0. 3Cr （atomic fraction, % ） superelastic alloys were comparatively investigated by differential scanning calorimeter （DSC） and tensile test. The results show that one-stage reversible transformation A→←R （ A-parent phase, R-R phase ） occurs upon heating →←cooling in 400 ℃ annealed Ti-50. 8Ni-0. 3Cr alloy, while the two-stage reversible transformation A→←R→←M （M-martensite） occurs upon heating →←cooling in other 3 alloys. Replacing Ni by Co, and replacing Ti by Cr and V, respectively, the R, M transformation temperature and transformation heat decrease, the M transformation temperature hysteresis increase, the R transformation temperature hysteresis has no significant change. All the 4 alloys show superelasticity at room temperature. After adding 1.0% Co and 0. 5% V, the superelastic stress goes down by 130MPa and 85 MPa, and the superelastic strain goes down by 1.8 and 2.4, respectively. After adding 0. 3% Cr, the superelastic stress of the alloy goes up by 147MPa, the superelastic strain goes down by 2. 9. After adding Co, Cr and V, the area of stress- strain loop of the alloys decreases.
出处
《金属热处理》
CAS
CSCD
北大核心
2008年第5期16-18,共3页
Heat Treatment of Metals
基金
陕西省自然科学基金项目(2005E121)
