爆炸复合制备非晶块体

Preparation of Bulk Metallic Glass by Explosive Composite

针对利用非晶薄带爆炸复合制备非晶块体面临的困难,提出在薄带表面涂镍使表面硬度降低,此举不仅可降低焊接下限,还可使焊接熔化区域集中于涂层上;同时,基于损伤力学的思想及焊接界面温升热软化模型对装置进行改进,通过在基座上增设缺陷界面,以削弱到达焊接界面的反射拉伸波强度从而提高焊接上限;以上举措使爆炸焊接窗口得以扩大,再根据多层薄带焊接动力学进行装药设计并试验;最后对制备所得样品进行X射线衍射、DSC及SEM测试,由X射线衍射及DSC曲线可知块体样品呈非晶态结构,而SEM照片则表明焊接界面结合良好。

In order to overcome the difficulty of preparing bulk metallic glasses by explosive composite, surfaces of amorphous foils were coated with Ni to decrease the surface hardness. Results show that this method can not only reduce the lower limit, but also assemble impacting between layers on Ni-layers. Besides, based on the damage mechanism and the model of thermo-softening at welding interfaces, defects in device of explosive welding were setted to accelerate the attenuation of tensile waves, so the tensile strength arrived at welding interfaces can be reduced. It can be concluded that the upper limit is increased. The welding window of foils was expanded by the mentioned above careful designing; then according to the dynamic model of the multi-layers amorphous foils explosive welding, the mass of explosive can be calculated. After experiment, a sample was tested by X-ray diffraction, DSC and SEM. Data of XRD and DSC can prove that the sample is bulk metallic glass, and images of SEM show that welding interfaces are satisfactory.