The results indicated that , the fabrication process of ultra - fine grain material is mainly determined by the stress , rotate speed and the flux of cooling water . the grain refining and the hardening effect are mostly affected by the rotate speed and the flux of cooling water . compared with commercial ly12 , the invalidate strength and the prolongation rate of the ultra - fine grain material are properly improved in the measurement of compression property ; and the abrupt change of the dilatability of the ultra - fine grain material at 500c is found ; also the phenomena of which the grain size of these microstructures is stable when annealed under 300c is observed 研究表明，采用本文提出的摩擦压扭强变形区转移法可以得到棒状的超细晶材料，轴向压力、扭转速度和温度是采用该方法制备超细晶材料的主控参数；试件的旋转转速和冷却速度对变形区晶粒细化和硬化效果影响显著；超细晶ly12的压缩性能与淬火+自然时效状态的ly12压缩性能相比，断裂强度和延伸率均有一定程度的增强；超细晶ly12的热膨胀系数在550左右发生明显的变化。
