【摘要】 AgSn合金内氧化后表层往往出现氧化物聚集层,导致成品中出现大量氧化物聚集,严重影响产品质量。针对上述问题,采用氧化-还原-氧化的交替氧化方法,即在通常内氧化工艺过程中增加还原-氧化步骤,先将氧化后丝材表面氧化层还原,然后再次氧化以获得均匀的组织。还原过程起关键作用,考察了不同还原温度(650℃、700℃、750℃)、不同还原时间(0.5h、1h、3h、5h)对银氧化锡内氧化后显微组织的影响,并优选了一种工艺进行后续加工。研究得出:表面还原层厚度随着还原温度的升高、时间的延长逐渐增加;由于晶界上原子排列较晶粒内部疏松,存在较多空位、位错等缺陷,导致晶界成为氢气快速扩散的通道,还原优先在晶界位置发生;后续加工后的丝材无明显氧化物聚集现象。更多还原

【Abstract】 Oxide aggregated layer exists in the surface of AgSn alloy after internal oxidization oxidation,which leads to a lot of oxide aggregates appear in the product and affects quality seriously.In response to these problems,we use the oxidation-deoxidizing-oxidation surface treatment method,that is to say,deoxidizing-oxidization step is added compared to the normal internal oxidation process.Firstly,the surface oxide aggregation is deoxidized,and then oxidizing is taken again to obtain homogeneous microstructures.Deoxidizing plays an important role in this process,thus the effect of different deoxidizing temperature（650℃,700℃,750℃）and time（0.5h,1h,3h,5h）on AgSnO₂ microstructure after internal oxidization were investigated.It is shown that the thickness of surface oxide aggregated layer increased gradually as the deoxidizing temperature and time increased.Atoms at grain boundary arranged looser than atoms in grains,there were more vacancies,dislocations and other defects,thus grain boundaries become a channel for rapid diffusion of hydrogen,as a result of which deoxidizing in internal wire occurred at grain boundaries preferentially.In addition,no obvious oxide aggregation in wire was observed after subsequent processing.更多还原