Hi Volker, Look carefully at the graph axis text, it is temperature difference between the two leads, not 0Centigrade to 40 centigrade room temps.
M K > From: [email protected] > To: [email protected] > Date: Thu, 30 May 2013 11:05:42 +0200 > Subject: Re: [volt-nuts] cadmium solder alloy for low thermal emf? > > > Hello > > >I do not imagine cadmium bearing solder being easy to acquire. The > > Wikipedia entry for solder says Pb90Sn10 can be used as a replacement > > for Cd70Sn30 in low thermal EMF applications: > > > > http://en.wikipedia.org/wiki/Solder > > > > On Thu, 30 May 2013 04:00:19 +0200, Volker Esper <[email protected]> > > wrote: > > > >> > >>By the way: does anyone know, if Agilent uses special solder alloy? I've > >>heard that a cadmium containing solder is used to get extremely low > >>thermoelectric voltages (or voltage differences). > >> > >>Is that right? If so, which alloy has to be used? > >> > >>Thanks > >> > >>Volker > >> > > Within LT AN86 Cd60Sn40 is recommended for a limited temperature range of 0 > to around 40 degrees. > http://cds.linear.com/docs/en/application-note/an86f.pdf > > But: the thermal EMF is only zero against copper. > Most precision integrated (hermetical) cirquits use Kovar. (39uV/K against > copper) > Relay contacts will be either copper berillium or another material. > So in most cases a optimized solder for copper/copper connections will not > be useful. > > On the other side Cd containing solders create very poisonous damps when > being heated. > > With best regards > > Andreas > > > _______________________________________________ > volt-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
