Long ago in another life I was involved with PCB Fab machines. Our etching systems used Titanium whenever metal parts were to be exposed to etchant. Pumps though would have been impossibly expensive in titanium, they were made of polymer or polymer coated SS. Any metal parts that could not be so coated were made of SS and designed to be easily replaced in routine servicing. Overall the designs specifically went out of their way to avoid this, especially fixings, even if it meant that the pumps were less efficient than they otherwise could have been. Regards Mike -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Adam Seychell Sent: Monday, April 16, 2007 8:53 AM To: [log in to unmask] Subject: [TN] stainless compatibility in alkaline etchant Does anyone know if stainless steel 316 corrodes when exposed to alkaline ammonia chloride etchants ? I have this diaphragm pump with internal stainless steel fasteners which are exposed to the etchant. The pump elastomers are EPDM and santoprene, and body material is glass filled polypropylene. I am wondering if the pump can be used for alkaline etchants. For a test I placed some stainless steel in etchant at let standing for one week. There was no visible surface corrosion, nor any measurable mass loss. I know this doesn't tell me I can use the pump and expect it to last. best regards, Adam Seychell --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 ----------------------------------------------------- ***This email, its content and any files transmitted with it are intended solely for the addressee(s) and may be legally privileged and/or confidential. If you are not the intended recipient please delete and contact the sender by return and delete the material from any computer. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. Messages sent via this medium may be subject to delays, non-delivery and unauthorized alteration. This email has been prepared using information believed by the author to be reliable and accurate, but Indium Corporation makes no warranty as to accuracy or completeness. In particular, Indium Corporation does not accept responsibility for changes made to this email after it was sent. Any opinions or recommendations expressed herein are solely those of the author. They may be subject to change without notice.*** --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 -----------------------------------------------------