【摘要】 利用铜模浇铸法制备了厚度为2 mm、成分为Mg65Cu22Ni3Y10块体合金试样,并通过X射线衍射、差热扫描量热仪证实其为完全的非晶态。以镁合金AM60B为母材、2 mm厚的Mg65Cu22Ni3Y10板状非晶态合金为中间层,在420~540℃下进行焊接,利用金相显微镜、扫描电镜(SEM)和能谱仪研究了焊接接头的微观形貌和成分分布。结果表明:界面接合良好,未观察到片状夹杂物、气孔及未焊合等缺陷;焊缝区由块状α-Mg相和针状化合物组成,基体中的Al元素通过晶界扩散偏聚到焊缝中,微量Y元素扩散到基体中,有少量的Mn和Cu元素发生偏聚,Ni元素分布均匀,没有发生偏聚现象。更多还原

【Abstract】 Bulk Mg65Cu22Ni3Y10 alloy with thickness of 2 mm was fabricated by casting in a traditional copper mould.Full amorphous structure was confirmed by X-ray diffractometry and differential scanning calorimetry(DSC).A welding experiment was performed using Mg-based alloys AM60B as base metal and bulk Mg65Cu22Ni3Y10 amorphous alloy as interlayer between 420 ℃ and 540 ℃.The microstructures and elements distribution of the brazed joints were analyzed by metallographic microscopy,SEM and EDS.The results show that a sound bonded interface is obtained without sheet inclusion,pore and unbinding.The microstructure consists of bulk α-Mg phase and needle compound in the weld metal,element Al diffuses along the grain boundary of the substrate into the welding line.A little Y diffuses into the base metal.A little Mn and Cu segregate and element Ni distributes homogeneously and no segregation appears in weld area.更多还原