From thermodyanmic calculation we obtain a ternary
eutectic at 0.91 wt.% Cu and 3.66 wt.% Ag at 216.3 C.
From the same calculation we obtain for the enthaply of
reaction (L->(Sn)+Ag3Sn+Cu6Sn5) -67.2 J/g.  This is
the enthalpy on freezing, on heating the sign is just
reversed.  Since this alloy is so Sn-rich the enthalpy
is very close to the one of pure tin which has an
enthalpy of melting of 59.2 J/g.

Ursula Kattner, Metallurgy Division, NIST

|  From [log in to unmask]  Wed Mar 15 15:39:58 2000
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|  Date: Wed, 15 Mar 2000 15:37:20 -0500
|  To: [log in to unmask]
|  From: Carol Handwerker <[log in to unmask]>
|  Subject: Question on Fwd: [LF] Heat of transformation
|  Mime-Version: 1.0
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|
|  >X-Lotus-FromDomain: IBMIT
|  >Date:         Mon, 13 Mar 2000 12:35:28 +0100
|  >Reply-To: "Leadfree Electronics Assembly E-Mail Forum." <[log in to unmask]>,
|  >        [log in to unmask]
|  >Sender: Leadfree <[log in to unmask]>
|  >From: "V. Sirtori" <[log in to unmask]>
|  >Subject:      [LF] Heat of transormation
|  >To: [log in to unmask]
|  >
|  >Does anyone know the heat of transformation both for the heating and the
|  >cooling of the alloy Sn-3.5Ag-0.75Cu?
|  >
|  >Many thanks and best regards.
|  >
|  >V. Sirtori
|  >Material Engineer
|  >Electronic Card Assembly Process Development
|  >Dept. VIM424
|  >Mail address: IBM ITALIA / via Lecco 61 / 20059 Vimercate / ITALY
|  >Phone: +39/039/6005253                        E-Mail :
|  >[log in to unmask]
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|  **************************************
|  Carol A. Handwerker
|  Chief, Metallurgy Division
|  NIST
|  100 Bureau Drive Stop 8550
|  Gaithersburg MD 20899-8550
|  Office:(301) 975-6158
|  Fax:(301) 975-4553
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---------------------------------------------------------------
Ursula R. Kattner             (e-mail: [log in to unmask])
Metallurgy Division, Materials Science & Engineering Laboratory
NIST,  100 Bureau Dr. Stop 8555,  Gaithersburg MD 20899-8555
Phone: 301-975-6044            Fax: 301-975-4553

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