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为了研究回流焊温度曲线对焊接缺陷产生的影响,同时研究在实际生产过程中温度曲线的设置如何以量化的方式代替传统的尝试式方式,本文主要从热效能的角度研究了回流焊温度曲线的升温区、保温区、回流区以及冷却区的温度时间变化,建立模型研究总热效能,并在保证这个值基本不变的条件下协调温度时间从而获得最优化的温度曲线,结合热效能和PCBA组装密度确定温度曲线的冷却速率,以焊接缺陷反推温度曲线设置的不足,结合热效能理念寻求解决办法。对焊膏的助焊剂活性从润湿力的角度研究导致缺陷的成因,并根据润湿力选择备选焊膏。
In order to study the effect of reflow temperature profile on the welding defects and to study how to set the temperature profile in the actual production process to replace the traditional trial-and-error approach in a quantitative way, this paper mainly studied the reflow temperature profile from the perspective of thermal efficiency Temperature, heating zone, reflow zone and cooling zone temperature, the model to study the total thermal efficiency, and to ensure that this value is basically the same conditions to coordinate the temperature and time to obtain the optimal temperature curve, combined with the thermal efficiency and PCBA The assembly density determines the cooling rate of the temperature curve, with the inadequate setback of the temperature profile of the welding flaw, combined with the thermal efficiency concept to find a solution. Flux activity on solder paste The cause of defects is investigated from the viewpoint of wetting force, and an alternative solder paste is selected based on wetting force.