Today is 2020-06-04 Thursday,Welcome to this site 

Company News

Analysis of The Reason Why The Solder Pad of Double Sided PCB Is Not Tinned

Word:[Big][Middle][Small] QR Code 2019-11-21     Viewed:    
  Our common computer board card is basically a double-sided PCB circuit board based on epoxy resin glass cloth,one side of which is the plug-in component and the other side is the component foot welding surface.It can be seen that the welding points are very regular.The component foot discrete welding surface of these welding points is called PCB pad.Ceramic substrate.Why don't other copper wires have tin on them.

  In addition to the solder pad and other parts requiring soldering,the surface of other parts has a layer of wave soldering resistance film.The appearance of the solder mask is mostly green,with a small amount of yellow,black,blue,etc.,so in PCB PCB industry,solder mask oil is often called green oil.The effect is to avoid bridging phenomenon during wave welding,improve welding quality and save solder.It is also the permanent protective layer of PCB,which can prevent moisture,corrosion,mildew and mechanical abrasion.From the outside,the smooth and bright green solder mask is the film heat curing green oil.Not only the appearance is more beautiful,it is important that its pad accuracy is higher,so as to improve the reliability of the solder joint.

  There are the following situations when PCB is not tinned.

  1.PCB is oxidized,and the PCB is not tinned.

  2.The temperature of the furnace is too low,or the speed is too fast,and the tin does not melt.

  3.For solder paste problem,you can try another solder paste.

  4.The problem of battery sheet is the most common one.As the battery sheet is usually made of stainless steel,a layer of chromium needs to be electroplated before tin can be applied.

  Ceramic substrate.If this electroplate layer has oil or electroplate bad,won't go up tin,you can try with soldering iron to see if can weld.Or put some solder paste on the battery chip,and then heat it on the soldering table or electric heating table to see if the battery chip can be tinned.

Ceramic substrate

Go Back
0562-2290098 0562-2296887