Hello RongJun Deng! Soldering to nickel finishes is typically done using
aggressive flux formulations because of the nickel oxide that forms on
nickel finishes. Check with your flux supplier to if the flux formulations
you are using are compatible for soldering nickel finishes.

Dave Hillman
Rockwell Collins

On Thu, Oct 29, 2015 at 2:32 AM, Deng RongJun <[log in to unmask]> wrote:

> Hi Technetters
>
> I have got a problem with a SMT type mini USB connector. The four pins
> contacted shield are no-wetting after reflow soldering.  But can be solder
> well by iron.
> The pins only plated by Nickel, is it possible the oxidation film creating
> on pin surface and then affect soldering?
>
> Picture:
> https://goo.gl/photos/qap1CBEWzUEJEc5i6
>
> Thanks in advance.
>
> RongJun Deng
>
>
> ______________________________________________________________________
> This email has been scanned by the Symantec Email Security.cloud service.
> For more information please contact helpdesk at x2960 or [log in to unmask]
> ______________________________________________________________________
>


______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________