快速凝固A1-Si基钎料性能的研究
Properties of rapidly solidified A1-Si base brazing filler alloys
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摘要: 利用单辊急冷设备和自制的双辊急冷设备,制得厚度为26~37μm和0.1~0.25mm的A1-Si基钎料薄带。在DuDont 1090设备上,用DSC测定了钎料的熔化特性,结果表明快凝态钎料液相点降低3~5℃,结晶温度区间缩小20℃左右,与普晶态钎料相比,快凝态钎料的润湿系数提高18%,强度提高28.4%,薄带钎料具有一定的柔性,便于某些场合使用,分析了钎料和钎缝的金相显微组织,测定了钎焊接义的抗拉强度。结果表明,当钎料成分相同时,快凝态钎料熔化温度低、强度高、组织细弥、润湿性好、接头强度波动小,是一种性能更优良的新颖钎料。Abstract: Ribbons of A1-Si base brazing filler alloys, which are 26-37μm and 0.1-0.25mm thick,arc produced on rapid solidiflcation cquipmcnt with single-and double-roller respcctivcly.By using a Dupont 1090 differcntial scanning calorimctcr (DSC),the melting properties of the ribbons are studied.The results show that the liquidus temperature is reduced by 3 to 5℃ and the interval of crystallization temperature by about 20℃,As compared with the brazing filler alloys of conventional cast,the ribbons produced by rapid solidification show some flexibility which enables them to be used preferably in some cases,and the wetting coefficient and tensile strength of the ribbons are increased by 18 and 28.4 percent respectively.Mierostructures of the ribbons and the brazing scams are examined.Tensile strength of the joints brazed with brazing filler of rapid solidiflcation and of conventional cast are tested.Analysis of the above results show that the rapidly solidifled new brazing filler alloys have superior properties of lower melting point,higher strength, finer crystal structure,better wettability and less fluctuation of strength in the brazing joints.