SMT 缺陷.pdf - 第23页
31 No Solder No Solder / / 无锡 Countermeasure/ 对策 1. Missing pr inting/ 漏印 Root cause: a) Stencil aperture was jammed./ 钢网堵孔 b) High viscosity of solder paste./ 锡膏粘性过高 Action: a) Clea n stencil;/ 清洗钢网 b) Replace the recyc…
30
No Solder
No Solder
/
/ 无锡
No solder to the land or termination where solder
is required.
焊点无锡
31
No Solder
No Solder
/
/ 无锡
Countermeasure/ 对策
1. Missing printing/ 漏印
Root cause: a) Stencil aperture was jammed./ 钢网堵孔
b) High viscosity of solder paste./ 锡膏粘性过高
Action: a) Clean stencil;/ 清洗钢网
b) Replace the recycled paste with fresh one./更换新锡膏
c) Printing machine parameter adjustment./校正丝印机参数
2. Poor solderability of component or pad./元件或焊盘可焊性太低
Root cause: a) Old date component or PCB. /陈旧元件或PCB板
b) Contamination on component or PCB. /元件或焊盘受污染
Action: Purge the material for further disposition. /清除来料
3. Insufficient flux volume: increase flux spray rate (wave solder).
助焊剂量不足: 增加助焊剂喷射量 (波峰焊接)
4. Preheat excess: lower preheat temperature properly (wave solder).
预热过度: 适当降低预热温度 (波峰焊)
5. Chip wave or solder wave height is low : proper height (wave solder).
波峰高度过低: 调整到适当高度 (波峰焊)
32
Insufficient Solder
Insufficient Solder
/
/
少
少锡
Insufficient
Insufficient solder
焊
焊锡不足