氮气保护在无铅化电子组装中的应用  

Application of N_2 Protection in Lead-free Electronic Assembly

作　　者：史建卫 杜彬 廖厅 王卫 

机构地区：[1]集适自动化科技(上海)有限公司深圳分公司,广东深圳518103 [2]中国电器科学研究院有限公司,广东广州510300

出　　处：《电子工业专用设备》2013年第10期27-35,共9页Equipment for Electronic Products Manufacturing

摘　　要：无铅钎料的高熔点、差润湿性给SMT传统的焊接工艺带来了很大冲击,并且对焊点质量也产生了很大的影响。为了防止氧化,改善钎料与焊盘、元件引脚之间的润湿性,提高产品合格率,目前在电子组装中普遍采用氮气保护。针对几种常用无铅钎料进行了氮气气氛中润湿性和焊点组织的分析,并初步研究了氮气保护对焊点质量和氧化渣的影响。结果表明:氮气保护可以改善无铅钎料润湿性,细化焊点组织,减少氧化渣量,而且对焊点外观和成品率也有一定的影响。The higher melting point and poorer wettability of lead-free solder impact on common soldering technology in SMT, as well as solder joint quality. In order to avoid oxidation and improve the wettability between solder and pad and lead of devices, N2 protection is adopted in electronic assembly popularly in order that the production quality will be improved. This article analyzes the wettability and solder joint structure of several common lead-free solders, and investigates the effect on solder joint quality and oxidation of solder under N2 protection. The result shows that N2 protection not only improves the wettability of lead-free solder, fines solder joint structure, and decreases amount of oxidation, but also affects the appearance of solder joint and ratio of finished production.

关 键 词：无铅化组装 无铅钎料 氮气保护 波峰焊 再流焊 润湿性 

分 类 号：TN605[电子电信—电路与系统]