You will find that though there are a number of candidate alloys with solidus >250C, few will be available as flux core according to supplier. You might also have to compromise on diameter. These alloys are not used in large enough amounts to warrant availability from stock in all possible combinations. My former colleagues will no doubt recall me grumbling: "It's not just melting point". You really do need to consider also surface finishes, service environment and stresses, max process temps, etc. Better to discuss the app with your supplier and determine the best alloy(s) for it and then the best presentation for applying it, keeping in mind that in-service performance generally trumps ease of application. Be aware higher melting point alloys generally are more difficult to form joints with and you might need to consider background heating to augment iron. Flux residues are likely to be harder to remove also due to increased thermal degradation. -- Regards Mike Fenner Bonding Services & Products M: +44 [0] 7810 526 317 T: +44 [0] 1865 522 663 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of McGlaughlin, Jeffrey A Sent: Wednesday, April 01, 2015 3:20 PM To: [log in to unmask] Subject: [TN] HIGH Temperature Solder I need to spec a high temperature wire solder for hand soldering. I need to have a solidus of greater than 250 degrees C. Is 90Pb10Sn my best/only choice or is there something else I should look at? Jeffrey McGlaughlin, C.I.D. Engineering Designer Avionics Systems & Tech Refersh Office: 614.424.7582| Fax: 614.458.7582 [log in to unmask]<mailto:[log in to unmask]> Battelle 505 King Avenue Columbus Ohio 43201-2693 http://www.battelle.org<http://www.battelle.org/> Connect with Battelle Facebook<http://www.facebook.com/battelle> | LinkedIn<http://www.linkedin.com/company/battelle> Twitter<http://www.twitter.com/Battelle> | YouTube<http://www.youtube.com/user/battelleinnovations> This message is intended only for the use of the individual or entity to which it is addressed, and may contain information that is privileged, confidential and/or otherwise exempt from disclosure under applicable law. If the reader of this message is not the intended recipient or the employee or agent responsible for delivering the message to the intended recipient, any disclosure, dissemination, distribution, copying or other use of this communication or its substance is prohibited. If you have received this communication in error, please return to the sender and delete from your computer system. ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________