How do I stress relieve nichrome V wire?
How do I stress relieve nichrome V wire?
(OP)
I have an application where we are using a nichrome v wire to move a contact. We have a mechanical adjustment to allow calibration of the contact. The calibration however when set during the day, and then verified the next day changes. We bake the unit containing the nichrome wire at 220 deg F for 12 hours. I think this is an attempt to stress relieve or stablize the nichrome wire. Does anyone know what temp would stress relieve the nichrome v wire?
James J Avalle
Jim Avalle Machine & Engineering Service
J.A.M.E.S.





RE: How do I stress relieve nichrome V wire?
I'm not sure what NiChrome alloy you are using but my Kanthal Percison book gives operating temps upwards of 2000*F for these alloys. I would try at least 1000*F and see. You can continually increse the temp until you get enough stress reliefe for your application.
Looking further into my guide gives the creep strength (1%elongation 1000 hrs) at 1470*F as 2160psi to 2900psi. Thsi rapidly drops off to <600psi as the temp goes to 1830*F. I'm gonna guess that you may get what you need at ~1800*F.
HTH
nick
RE: How do I stress relieve nichrome V wire?