There are plasma nozzles which use normal atmosphere to surface treat pcb assemblies (and which are safe on the circuitry). They can be set up on automation to do a number of simple passes of the pcb to get full coverage in an acceptable time. I can see that if the board topography were too extreme (skyscrapers), then it might get a bit tricky.
Regards,
Peter
--------------------------------------------------------
Peter Swanson
Managing Director
INTERTRONICS, Oxford, England
t 01865 842842
m 07785 908556
e [log in to unmask]
w www.intertronics.co.uk
Read our news! http://www.intertronics.co.uk/blog/blog.htm
INTERTRONICS is the trading name of Cygnet Electronics Ltd,
registered in England No 1835617. Registered office:
12a Station Field Industrial Estate, KIDLINGTON, Oxfordshire, OX5 1JD, ENGLAND
INTERTRONICS is certified to ISO 9001:2015
-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Douglas Pauls
Sent: 06 March 2019 21:05
To: [log in to unmask]
Subject: Re: [TN] [External] Re: [TN] Plasma before Coating
I would agree. Every time I have looked at open air plasma, it appears that it works well for flat substrates, like bare boards, but not for full assemblies with any kind of topography.
Out of curiosity, when you vacuum plasma, what gas are you using? We generally use argon so as not to blacken silver parts.
*Douglas Pauls *| Principal Materials and Process Engr | Advanced Operations Engineering
*COLLINS AEROSPACE*
400 Collins Road NE, MS 108-101, Cedar Rapids, IA 52498 USA
*Tel:* +1 319 295 2109 | *Mobile: *+1 319 431 3773
[log in to unmask]
On Wed, Mar 6, 2019 at 1:50 PM lduso - Diamond-MT.com <[log in to unmask]>
wrote:
> Not as a standard procedure on CCAs but a couple here and there. It
> came about due to poor surface energy tests and it does help. Quite
> often on metallic parts like stainless steel and nickel before
> parylene coating. All done in a vacuum. Although I would love to try open-air plasma.
>
> Lloyd Duso
> General Manager
> Diamond-MT
> (814) 535-3505
> www.Diamond-mt.com
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.Diamond-2Dmt.
> com&d=DwMFaQ&c=ilBQI1lupc9Y65XwNblLtw&r=lTRDjB8ojaf7ZaJ9DHeDAm7e-HFP9f
> xIkv6fRnV49HE&m=w13JU2W1V8UO5sePYWQBU04jy9DhgL4qXpKHfLaXFpA&s=xlQdpAXq
> DTjxXvzI2GcrjVv6--XbIxDd8PTkCsO-6WE&e=>
>
>
> On Wed, Mar 6, 2019 at 2:42 PM Douglas Pauls <
> [log in to unmask]> wrote:
>
>> Good morning all,
>> Are any of you routinely treating assembly surfaces with plasma prior
>> to conformal coating? We do not, except for very niche applications,
>> but I wanted to see if that was a mainstream process for anyone else.
>>
>> *Douglas Pauls *| Principal Materials and Process Engr | Advanced
>> Operations Engineering
>>
>> *COLLINS AEROSPACE*
>>
>> 400 Collins Road NE, MS 108-101, Cedar Rapids, IA 52498 USA
>>
>> *Tel:* +1 319 295 2109 | *Mobile: *+1 319 431 3773
>>
>> [log in to unmask]
>>
>
|
