Hello Victor - the problem you have encountered is due to the nature of the
plating bath formulations. There are clear differences in an ENIG plating
bath and a Hard Gold plating bath due to the bath constituents along with
the plating deposit itself. The differences in bright acid tin plating and
matte tin plating doesn't appear to have the same distinguishing
characteristics. A number of the industry tin whisker committees I
participate on have investigated your question, hoping to produce a clear
definition of what a "bright acid" versus a "matte" tin plating would be.
The committees have not been able to find a consensus definition, partially
due to plating bath formulation proprietary information and partially due
to some of the difference between bright acid tin versus matte tin is the
plating deposition parameters. Plating deposit attributes such as a
distinguishing grain size  or a carbon content level were researched
without success. A very good reference on tin plating is: The
Electrodeposition of Tin and its Alloys, M. Jordan, ISBN3-87480-118-7. I am
not much of a believer in using visual appearance as a plating
identification method as sometimes you can get fooled.

Dave

On Wed, Jan 4, 2017 at 6:35 AM, <[log in to unmask]> wrote:

>
> *Dell - Internal Use - Confidential *
> David,
>
>    Can I distinguish the tin plating process by SEM/EDX analysis.
> Perhaps by an element different in the processes.
>
>    I have also asked about the process difference between ENIG, P
> elements, and HARD GOLD plating, non P element, process when the XRF values
> are below 10 micro inches of gold.   The 10 micro inches value thickness is
> found in ENIG and hard gold plating process.
>
> Victor,
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask] <[log in to unmask]>] On Behalf Of
> David Hillman
> Sent: Tuesday, January 03, 2017 4:32 PM
> To: [log in to unmask]
> Subject: Re: [TN] Tin plating Process
>
> Hi Victor - nope and if someone tells you they can, I would suggest
> walking away very quickly. A number of the industry committees have chased
> this question in terms of grain size, chemistry, carbon content, etc. and
> have come away very unsatisfied with the results. The best way to
> understand a bright acid tin versus a matte tin plating deposit is to team
> with the component supplier/plater to understand the deposition
> characteristics of the bath.
>
> Dave Hillman
> Rockwell Collins
> [log in to unmask]
>
>
> On Tue, Jan 3, 2017 at 3:06 PM, <[log in to unmask]> wrote:
>
> > Fellow TechNetters:
> >
> >     Can I VISUALLY tell the difference between tin plating process,
> > bright and matte tin?
> >
> > Victor,
> >
>
>