【作者】 苗丽莎；

【导师】 曹彪； 陈和平；

【作者基本信息】 华南理工大学 ， 机械工程， 2011， 硕士

【摘要】 热压回流焊是基于回流焊和压焊的一种焊接手段,通过焊头向工件施加一定压力,使工件紧贴焊头,由流过焊头的电流产生的电阻热熔化工件焊点预置的钎料,实现排线或引线与金属薄层表面的回流焊。热压回流焊过程中,焊头焊接面温度分布是影响焊接质量的关键因素,与焊头的材料、几何结构,以及通电时间、散热等有关,随着绿色钎料发展,热压回流焊工艺窗口变窄,对焊头温度分布的均匀性提出了更高的要求。论文针对热压回流焊焊头的温度分布进行研究,通过ANSYS有限元分析软件建立焊头温度分布的电热模型,用ANSYS的参数化设计语言(APDL)对模拟求解过程进行控制,实现热压回流焊过程中的各阶段自动求解转换。将模拟结果与所设计的红外测温实验采集的热图像进行比对,表明模拟结果是准确的。建立焊头工作面温度场的几个重要性能指标作为判定条件,基于所建电热模型,利用单因素分析方法对焊头结构进行优化设计;研究升温速度和回流温度对焊头温度场分布的影响。得到了焊头关键结构尺寸、加热速度和回流温度对焊头温度场的影响规律,设计所得到焊头的温度分布与初始焊头相比较,温度分布得到了较大的改善。研究实现了焊头设计过程中温度场的可视化,所建立的焊头有限元模型能够有效的辅助焊头设计,缩短设计周期。更多还原

【Abstract】 Hot-pressing reflow soldering is a welding method based on reflow soldering and bonding. The workpiece is abutted to the electrode by the clamping force transferred by the electrode. The joule heat produced by the heated electrode passes through the abutted surface into the joint and causes the melt of preset solder. The process of reflow soldering achieves between the slender wears and the metallic coat.The temperature distribution of the working face which is a crucial influencing factor to the weld quality of hot-pressing reflow sodering is related to these influencing factors including workpiece diversity, different electrode structures and materials, current form and radiation. With the development of lead-free solder alloy, more strict technological parameter is demanded, which requires more better uniformity to the acting face. This paper designs infrared detecting experiment to get the thermograph during the heating process of electrode. The electrode temperature distribution simulation is achieved based on ANSYS. The continuous between each step of the solution process is achieved under the controlling of APDL program.The comparison between simulation result and the thermograph proves that simulation of the electrode is feasible.Based on the FEA model, several crucial property criterion of the acting face temperature distribution is established and a simple factor comparison system is designed to determine the optimization electrode. The effect of reflow soldering heating rate and reflow temperature on electrode temperature distribution is analysised under the optimization electrode model. The influence law of crucial structure size, reflow soldering heating rate and reflow temperature is obtained. The comprasion between optimization electode and initial electrode shows that the temperature distribution has been apparently improved.The FEA model of hot-press reflow soldering electrode based on ANSYS can simulate the temperature distribution in electrode effectively. The research achieves the electrode temperature distribution visualization during design procedure and shortens the electrode design process too.更多还原