作　　者： ; ; ; ;

机构地区： 哈尔滨工业大学材料科学与工程学院

出　　处： 《金属学报》 2005年第3期291-296,共6页

摘　　要： Zr41.25Ti13.75Ni10Cu12.5Be22.5块体非晶合金在过冷液相区内的拉伸断裂行为与拉伸温度及应变速率有关.在室温 条件下拉伸表现为剪切带扩展形成脆性断裂,在断口表面层出现了大量放射状脉状纹络,断口表面层的绝热升温现象导致断裂层温 度超过了液相线温度,从而在断面上出现熔融状液滴.在玻璃化转变温度点,断裂模式依然为脆性断裂,韧窝状形貌及脉状纹络代 替了放射状的脉状纹络分布于断口表面,同时伴随有熔融状液滴.计算表明,断口表面层绝热升温温度依然高于液相线温度.在更 高温度或较低应变速率条件下,断裂方式转变为颈缩断裂模式,在颈缩点顶端依然存在脉状纹络,而未能观察到熔融状液滴.分析 表明,在较高温度或较低应变速率条件下,绝热升温对断裂层的影响非常微弱,断口表层的温度没有明显升高. The tension fracture behavior of Zr41.25Ti13.75Ni10Cu12.5Be22.5 bulk metallic glass is associated with the test temperature and strain rate. At room temperature, the brittle fracture is dominated by the shear band's formation and expansion. A large amount of radiating vein-like morphologies and the liquid droplets can be observed on the fracture surface. The calculation found that the adiabatic heating makes the temperature of the fracture surface layer higher than the liquidus temperature. At the glass transition temperature, the fracture mode is still brittle fracture. Dimples, vein-like morphologies and liquid droplets occupy the fracture surface. The adiabatic heating induces the temperature of fracture surface layer to be higher than the liquidus temperature too. With the temperature increasing or the strain rate decreasing, the necking fracture appears. The fracture surface displays the vein-like morphologies without the liquid droplets. The affection of the adiabatic heating is so weak that the temperature of the fracture surface layer can not increase obviously.

关 键 词： 锆基块体非晶合金 拉伸变形 断裂行为 绝热升温

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]