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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Copper Tungsten: Activation / Plating / Surface Treatment
Q. Hi. I work in a chemical-processing job shop and we received parts made of copper-tungsten per ASTM B702 for plating (copper strike, EN & gold).
I have never heard of this "alloy" (it's not actually an alloy, but a metal matrix composite) and can't find any information in the surface engineering literature on how to prepare it for plating.
Is there anyone here who has experience plating this alloy?
Thanks in advance,
- Norwood, Massachusetts, USA
February 16, 2022
A. ASTM B482, "Standard Practice for preparation of Tungsten and Tungsten ALLOYS for Electroplating", however, my 1985 copy does not mention the word "copper".
Robert H Probert
Robert H Probert Technical Services
Garner, North Carolina
February 21, 2022
Thanks Robert.
For activation that specification calls for either an electrolytic hydrofluoric-acid cleaner or a chrome strike, neither of which I've ever seen before and, of course, both are very dangerous chemicals.
Fortunately, though, the parts appeared to be very clean and we obtained a very good result with just a quick direct/reverse electro-clean followed by nickel strike and cyanide-copper flash.
- Norwood, Massachusetts, USA
February 28, 2022
⇩ Related postings, oldest first ⇩
1998
Hi,
Q. I would like to seek your expertise on the surface treatment on Tungsten/Copper. Currently, I have a Tungsten/Copper material pick-up tip which is heated to a temperature of around 300 degree C in one of our machine. After a constant heating for a day, I realized that the tip becomes scaly and it affects the performance of the tip. I would like to know of any surface treatment that is commercially and easily available for such material. For your information, the Tungsten/Copper material which I am using now has yet sent for any surface treatment. Thank you.
With Regards,
Choon-Yen Chow- Singapore
A. Soldering iron tips are plated with iron to make them last longer. What does your pick-up tip pick up?
Tom Pullizzi
Falls Township, Pennsylvania
1998
Q. I want to know, in order to activate copper tungsten (85% copper-15%tungsten) what is the appropriate procedure?
Kenneth Lim Jee Huat- Ipoh, Malaysia
2001
A. Cycles for tungsten include anodic cleaning, HCl, HF, chromium strike. Also find ASTM B482, 'Standard Practice for Preparation of Tungsten and Tungsten Alloys for Electroplating'.
Tom Pullizzi
Falls Township, Pennsylvania
2001
A. No doubt this is a "Metal Matrix Composite" and not an alloy. Usually formed by sintering Tungsten Powder into a block then pouring molten Copper into the metal matrix under vacuum. Then machined into heat spreaders for high frequency Integrated Circuits like microwave components. What kills the plating here is the black "goo" that oozes out when its heated...leftover sintering binder. Lifts the plating right off. Also you have millions of Cu/W bimetallic galvanic joints all over the surface...and the Tungsten takes on a "tenacious" oxide. Plating this to withstand IC reliability specs requires much, much more than just a standard Tungsten-Copper Alloy pretreatment. These recipes are, however, proprietary. You really need to hire a good consultant if you wish to enter this business.
Dave Kinghorn
Chemical Engineer
SUNNYvale, California
2001
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