The famous Silicon Valley RLM process was selective solder over tin/nickel. We perfected the tin/nickel at H-P's Porter Dr. PCB facility in 1967 and used it as a final finish for many years. It is almost straight out of the "Metal Finishing Handbook" as the 'chloride/fluoride' bath with pure tin anodes. When I joined them in 1969, I started to use a Gold Flash or a Bright Tin Flash over the tin/nickel because it was so hard to solder to after the protective oxide had formed on its surface. But it is a remarkable alloy with properties far better than nickel or tin. IF YOU COULD CONTROL THE STRESS! Happy Holden APM Steve Hodge <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 08/17/2005 04:31 PM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to Steve Hodge <[log in to unmask]> To [log in to unmask] cc Subject HASL over nickel I believe the process for the selective solder over nickel (RLM) used tin/nickel and not pure sulfamate nickel. In the case I cited, we had to put on the immersion gold to prevent passivation in between nickel and HASL processes. At 02:12 PM 08/17/2005, you wrote: >Which works for a plating process, not too sure if the same applies where >the nickel is happily oxidizing all of the time it is out of a plating tank. > >John > >------------------------------------ >Avanex >John Burke >Senior Manager RoHS Compliance >[log in to unmask] >40919 Encyclopedia Circle >Fremont >CA 94538 >tel: 510 897 4250 >fax: 510 979 0189 >mobile: 510 676 6312 >-----Original Message----- >From: TechNet [mailto:[log in to unmask]]On Behalf Of Scott B. Westheimer >Sent: Wednesday, August 17, 2005 1:01 PM >To: [log in to unmask] >Subject: Re: [TN] HASL over nickel > > >The was actually a process back in the 70's called RLM. For you that worked >in Silicon Valley back then it stood for Robert L Mac the owner of Santa >Clara Circuits who had the process patented. It was a nickel plated board >that was then covered completed with screen ink, sorry no dry film back >then, except for the pads and then tin leaded plated and reflowed. Was there >any issues? Not sure but there was a lot of boards made that way, for >several years. > >Scott B. Westheimer >Colonial Circuits --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------