机械球磨和高压对Co相变的影响  

Effects of Mechanical Milling and High Pressure on Phase Transition of Cobalt

作　　者：刘力[1] 姚斌[2] 丁战辉[2] 曹幼章[1] 郭秀芝[1] 苏文辉[2] 

机构地区：[1]北华大学理学院物理系,吉林省吉林132013 [2]吉林大学物理学院,长春130021

出　　处：《吉林大学学报（理学版）》2006年第6期959-962,共4页Journal of Jilin University:Science Edition

基　　金：国家自然科学基金(批准号:50472003);教育部博士点基金(批准号:20040183063)

摘　　要：通过高能球磨和高压技术对Co的相变过程及其机制进行研究,结果表明,具有六角密积结构的α-Co经60 h高能球磨后完全转变为具有面心立方结构的-βCo,但继续球磨直到120 h,未观察到β-Co向α-Co的逆转变.由于球磨碰撞引起的缺陷层错和局域温度导致α-Co到β-Co的转变.研究发现,高压下-βCo向α-Co相转变,由于-βCo向α-Co的相转变为无扩散相变,因此,压力可使其形核热力学势垒降低,即压力对β-Co向α-Co的相转变具有促进作用.Phase transition of cobalt induced by mechanical milling and high pressure and its transition mechanisms were studied, α-Co with the hcp. structure completely transformed to β-Co with the fcc. structure after milling for 60 h due to the stacking fault and local temperature resulted from impact and shear force of steel balls during the milling process. However, the reverse transition from β-Co to α-Co was not observed, even milling up to 120 h. The reverse transition was studied under high pressure, and it was found that pressure can accelerate the transition from β-Co to α-Co, which is due to that this transformation is a diffusionless one and its thermodynamic barrier decreases by pressuring.

关 键 词：相变 CO 高压 机械球磨 

分 类 号：O521.2[理学—高压高温物理]