回流焊常见缺陷的分析报告方案.doc

南京信息职业技术学院 毕业设计论文 作者 王 浩 学号 21124P29 系部 机电学院 专业 电子组装技术与设备(通信设备制造) 题目 回流焊常见缺陷的分析 指导教师 谭淑英 高晴 评阅教师 完成时间： 2014年 05月 15 日 毕业设计(论文)中文摘要 题目：回流焊常见缺陷的分析 摘要：元器件的微型化和产品的多功能化，驱动了产品安装设计的高密度化和立体化。其特点是焊点越来越密集、焊点尺寸越来越微小、间距越来越细。焊接缺陷是影响电子产品质量的主要因素，为了保证表面贴装电子产品的质量，对表面贴装工艺的核心环节回流焊的工艺特点进行了分析，讨论了回流焊的温度曲线特点和影响回流焊焊接质量的几个主要因素，并根据回流焊的温度和工艺特点对回流焊焊接过程中出现的锡珠、桥连、芯吸、空洞、曼哈顿现象、PCB扭曲等几种常见的焊接缺陷及其成因进行了分析，提出了相应的解决对策。通过这些措施，有效的降低了焊接缺陷的出现率，提高了回流焊的焊接质量。 关键词：表面贴装技术 回流焊 焊接缺陷 预防措施 毕业设计(论文)外文摘要 Title : Solder Defects in Reflow Soldering Process Abstract: With component micromation and product multifunction, the product design three-dimensional assembly andintegration. It is of the characteristics of high integration and small size and fine pitch more and more. Solder defects are oneof the major factors which have an impact on electronic product quality. In order to ensure the quality of surface-mount electronic products，the temperature characteristics of reflowsoldering，which is the key process of surface mount technology were analyzed and the characteristics of the reflow profileand the major factors which affect the quality of the reflow soldering were discussed．According to the characteristics ofrefiow temperature and technology,the causes and phenomenon of coliIxnon defects occured in reflow soldering，such 88，wicking，bridging，voiding,solder bailing，PCB distortion and opening of IC pin were analyzed and some effective solution methods were put forward．These measures can effectively reduce．the occurrence rate of the welding defects and improve the welding quality of the reflow soldering． keywords: surface mount technology(SMT)； reflow soldering； oldering defects； preventive measure 目录 1引 言......................................................1 2 影响回流焊焊接质量的因素........................................1 2.1 PCB焊盘设计..........................