摘要
无论是有铅工艺还是无铅工艺,大多数EMS均采用免清洗技术,但对于要求比较严格的军用类、医疗器械类及汽车电子类生产厂家则仍然要求焊后清洗。作为军品类电子产品印制板组装件清洗后的洁净度满足GJB5807-2006军用印制板组装件焊后清洗要求:三级电子产品,用五倍放大镜检查印制板组装件表面应无残留物存在,印制板表面离子残留物含量不大于1.56μg(NaCl)/cm2。通过试验研究发现:在清洗剂一定的情况下,选用不同的焊膏,焊后清洗的效果不同;另外,焊接结束与清洗前间隔时间的长短,也是影响清洗效果的重要因素。采用Loctite CR37 63Sn37Pb和Alpha UP78 63Sn37Pb两种焊膏与VIGON A 200的水基清洗剂在焊后1h之内进行清洗,可得到较好的清洗效果。
NO-clean soldering technology has been widely used by most of EMS in either SnPb or No-lead process But PCB after soldering used in the military,medical and automobile electrical product must be cleaned,and the cleanliness of the PCA should meet the requirements of GJB5807-2006:no flux residues on the surface of PCB and the amount of Iron≤ 1.56 μg (NaCl)/cm^2.The result indicated that the right match of the paste and the solvent for cleaning and the time between soldering and cleaning have grate influence on the cleanliness of PCB.And the result of experiment was that solvent VIGON A 200 could clean the flux residues of the paste LOCTITE CR37 63Sn37Pb and Alpha UP78 63Sn37Pb and the PCB would be cleaned within one hour after soldering.
出处
《电焊机》
2008年第9期69-72,共4页
Electric Welding Machine