From ibmwrNoSpam@NoSpamworld.std.com Fri May 30 16:08:54 1997 From: "Karsten Stig Rasmussen" To: Subject: Re: BMW: Fram PH6063 & metallurgy... Date: Fri, 30 May 1997 21:24:31 +0200 X-Priority: 3 Reply-To: "Karsten Stig Rasmussen" ------------------------------ Date: Fri, 30 May 1997 08:47:45 -0700 (PDT) From: Tom Nicholas Subject: Re: BMW: Fram PH6063 & metallurgy... --------------------- Good, I _do_ know what annealing is. 'Never heard of it being done to copper, but... Heating aluminum until it, "glows"? > Really, I only reuse crush gaskets once or twice and I only take > the time to anneal them because it's fun and it annoys Diaz. As > you can imagine, after a couple smushes the crush gaskets start to > lose it dimensionally. >Tom. ---------------------- Hi guys. I do a little bit of metallurgy, too, at the Technical University of Denmark. One kind of annealing is the total recrystallization ("softest result", no deformation hardening or other hardening left). The pure metals recrystallize completely (give or take a little) in _one_hour_ at the following temperatures (degrees Celsius, sorry): Sn (tin ) room temp., instantly! Al (aluminum) 150 Mg (magnesium) 150 Cu (copper) 220 = 428 deg. F Fe (iron) 450 W (tungsten) 1200 At this temperature, far from the melting points, no dimensional loss occurs so you can shape it (e.g. your gasket with a hammer?) if it's lost it, then recrystallize it. After each recrystallization (complete in one hour at 220 deg. C) the metal will be exactly as new. ...my 25 xre worth. Hope it'll reproduce the o with the / correctly... Sincerely, Karsten Stig Rasmussen ******************************* KSRNoSpam@NoSpamostenfeld.dtu.dk ******************************* Member of the Board of PMC DK Polytechnical MC Club Denmark http:\\www.pmc.dk (Not yet in English)