CoMn合金中的马氏体相变和形状记忆效应

Martensitic Transformation and Shape Memory Effect in CoMn Alloy

研究了 Co Mn合金中的 γ(fcc)→ ε(hcp)马氏体相变 ,并测量了合金的形状记忆效应(SME) .结果表明 ,该合金的马氏体相变具有典型的 γ→ ε马氏体相变特征 ,它在发生马氏体相变时 ,内耗峰并不对应于母相模量的下降 ,其形核无需籍软模或区域软模 .通过训练可以改善 Co Mn合金的 SME,对改善的原因进行了初步的探讨 .

Co based alloys exhibit fcc( γ )→hcp( ε ) martensitic transformation. Since the stacking fault energy and driving force of martensitic transformation in Co based alloys are quite low, a /6〈112〉 Shockley partial dislocations are easy to move under the applied magnetic field, which implies that Co based alloys are potential magneto shape memory materials. The martensitic transformation γ (fcc)→ ε (hcp) and shape memory effect (SME) in CoMn alloy was studied. The results show that the transformation of the alloy has traditional characteristics of γ→ε martensitic transformation. The internal peak of the sample does not correspond to decrease of the modulus, which means that the martensitic transformation does not need soft mode. The SME of the alloy is found to be increased after training. The reason of improving SME was investigated.