13.Leaching( 端子熔化 )

拒收 良好r

缺c描述 :

 

Metallization of the component has disappeared and material of the component’s body visible.

金俣俗尤刍零件底材露出

允收 :

Leaching not exceeding 25% of width or thickness is not consider to be a defect.

零件器特性o影 , 且融融比率小於 25%

可能因素 :

• Tin component of the solder dissolved the metallization of components
• 焊a分解零件a端子
• Immersion time or contact length with solder too long
• 焊接rg久或囟冗^高

 

可行的A防方法 :

• Ensure that the tin component of solder will not dissolve the metallization of components
• _保零件a端子不被焊a熔解
• Select components with metallization that would not dissolve in the solder
• 慎x端子材|不被焊a熔解
• Ensure that the immersion or contact time is not too long
• _保焊囟扰crg不太大

重工注意事 :

For SMD :
Preheating is necessary to soften the adhesive joint between the SMD and board so that it is easier to break by twisting when desoldered.A preheat temperature higher that the glass-transition temperature( 60°C / 140°F ~ 80°C / 180°F ) of the adhesive is necessary.The solder joint is desoldered with the help of a chisel-shaped soldering tip and solder wick.The solder wick should be pressed into the corner long enough to let the heat travel into the gap underneath the component so that the solder is sucked out and the damaged component is replaced by another good one.