摘要
利用快速凝固技术和传统铸造技术分别制备出成分相同的Al-Cu快冷钎料薄带和普通钎料.将2种钎料在4种钎焊温度(590、600、610、620℃)和4种保温时间(5、10、15、20 min)下与纯铝进行真空钎焊,借助差热分析(DTA)、扫描电镜(SEM)、X衍射(XRD)、能量色散谱仪(EDS)对2种钎料的熔点、钎缝微观组织和Cu元素的扩散行为进行了研究.研究结果表明:快冷钎料元素分布均匀,晶粒细小,晶粒形态为胞状,而普通钎料成分有偏析,元素分布不均匀,且晶粒大小不一,晶粒形态多为枝晶;快冷钎料的熔点比普通钎料的熔点低3.0℃,结晶区间缩小1.2℃.在相同的钎焊条件下,快冷钎料Cu元素的扩散能力均比普通钎料的扩散能力强.钎焊温度较低时,普通钎料和快冷钎料的Cu元素的扩散能力差别较大;随着钎焊温度的升高和保温时间的延长,两者的差别减小.
The brazing ribbons and as-cast solder of Al-Cu with the same compositions were prepared by means of rapid solidification and ordinary casting method, respectively. These two kinds of solders were used to pure braze aluminum with vacuum brazing at 590,600,610, and 620 ℃ during the time periods of temperature holding as 5,10, 15, and 20 min. The melting points, microstructures, and diffusibility of Cu were studied with DTA, SEM, X-ray,and EDS. The results showed that the elements of the rapid solidified solder ribbons have homogeneous structure and very small crystal grain size and, as to the ordinary Al- Cu solders,there was crystal segregation and pine-tree crystal. Its melting point was lower than that of ordinary Al-Cu solder by 3. 0 ℃, and crystallizing range is narrower than that of ordinary Al-Cu solder by 1. 2 ℃. When the soldering temperature and soldering heat-retaining period was identical, the Cu diffusibility of the rapid solidified solder was remarkably higher than that of the ordinary solder. Discrimination of diffusivity reduced with the increase of soldering temperature and prolonged heat-retaining period.
出处
《兰州理工大学学报》
CAS
北大核心
2006年第2期9-13,共5页
Journal of Lanzhou University of Technology
基金
甘肃省中青年科技基金(YS021-A22-017)
关键词
快速凝固
快冷钎料
真空钎焊
扩散
rapid solidification
rapid solidification solder
vacuum brazing
diffusion
