CAJ | 학술논문

采用高分辨率电镀观测铸态Zr60Al15Ni25的微观结构.X-射线分析表明,铸态Zr60Al15Ni25合金为非晶态,而通过高分辨电镜发现非晶合金中存在大量的短程有序区.实验发现,非晶合金的无序程度与相对应的母合金铸锭的凝固组织密切相关.通过差示扫描量热法研究非晶合金在线性加热和等温条件下的晶化动力学.结果表明:非晶合金的晶化是预先存在的短程有序区作为晶核长大开始的三维扩散控制的过程.Zr60Al15Ni25块体非晶合金的无序程度对其晶化动力学具有明显的影响,即无序程度越大,非晶合金的晶化越迟缓.
채용고분변솔전도관측주태Zr60Al15Ni25적미관결구.X-사선분석표명,주태Zr60Al15Ni25합금위비정태,이통과고분변전경발현비정합금중존재대량적단정유서구.실험발현,비정합금적무서정도여상대응적모합금주정적응고조직밀절상관.통과차시소묘량열법연구비정합금재선성가열화등온조건하적정화동역학.결과표명:비정합금적정화시예선존재적단정유서구작위정핵장대개시적삼유확산공제적과정.Zr60Al15Ni25괴체비정합금적무서정도대기정화동역학구유명현적영향,즉무서정도월대,비정합금적정화월지완.
The microstructure of as-cast Zr60Al15Ni25 bulk metallic glass was investigated by high-resolution transmission electron microscopy.It is found that there exist numerous short-range order regions (SRORs) in the metallic glass though it is identified to be amorphous by X-ray diffraction method.Furthermore,the amorphous degree shows a close correlation with the microstructure of corresponding mother ingot.The crystallization kinetics was investigated by differential scanning calorimetry under isochronal and isothermal conditions.The results show that the crystallization is triggered by the growth of the pre-existing SRORs and the growth isthree-dimension diffusion-controlled.The amorphous degree of Zr60Al15Ni25 bulk metallic glass considerably influences its crystallization kinetics,namely,the more homogeneous distribution of atoms results in a more sluggish nucleation behavior.