冷加工和热处理对Nb及Nb合金弹性性能的影响

INFLUENCE OF COLD-WORKING AND HEAT-TREATING ON ELASTIC PROPERTIES OF Nb AND Nb-BASE ALLOYS

研究了冷加工和热处理对Nb及两种Nb基弹性合金弹性性能(包括弹性极限、弹性模量以及弹模温度系数)的影响。试验结果表明:(1)Nb—2Mo—2Zr—1Ti单相合金回复态弹性极限较冷轧态及再结晶态的皆高。时效硬化型合金Nb—40Ti—5.5Al,尽管冷轧态弹性极限较低,但经时效处理,弹性极限增加较多,而弹性模量只有少量变化,从而储能比(σ_?~2/E)大大增加(2)强烈冷变形态及再结晶态纯Nb弹性模量随温度变化(E—T)关系皆存在反常升高现象。强烈冷变形态Nb经600℃,4h处理,(回复态),E—T反常关系消失;而再结晶Nb经600℃,4h处理,反常关系不起变化。本文还讨论了无磁性的Nb弹性反常机理。

The elastic limit of single--phase alloy Nb--2Mo--2Zr--1Ti is higher as recovered state in comparison with as cold--rolled or recrystallized one. For Nb--40Ti--5.5Al alloy of age--hardening type, the elastic limit is lower as cold--rolled state, but increases considerably after proper aging. However, its elastic modulus changes no more, so the stored--energy (σ_e^2/E) may raise significantly. The temperature dependence on elastic modulus for pure Nb as intensely cold--worked or recrystallized state is anomalous. This anomaly may disappear after reco vered treatment of intensely cold--worked state at 600℃ for 4h, and may change no more after that of recrystallized state. The anomalous behaviour of elasticity was also discussed on the non--magnetic Nb.