A study of the kinetics and energetics of solid state reactions in Pd/Sn diffusion couples

Book · Tue Dec 31 04:00:00 EST 1996

OSTI ID:479281

Chromik, R R; Cotts, E J ^[1]

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1. State Univ. of New York, Binghamton, NY (United States)

Using differential scanning calorimetry, supplemented by measurements from scanning electron microscopy images, the authors have investigated solid state reactions in Pd/Sn multilayer composites to form PdSn{sub 4} and PdSn{sub 3}. Planar diffusion couples of Pd and Sn were prepared by means of mechanical co-deformation in a rolling mill. A phase formation sequences was determined using differential scanning calorimetry and x-ray diffraction. Growth of the PdSn{sub 4} phase was studied from room temperature to the melting point of Sn. For temperatures between 430 and 460 K diffusion limited growth of PdSn{sub 4} was observed. From heat flow data over this limited temperature range, the form of the reaction constant was found to be k{sup 2} = k{sub 0} exp({minus}E{sub a}/k{sub b}T), where k{sub 0} = 0.16 cm{sup 2}/s and E{sub a} = 0.8 eV/atom. Also determined was a heat of formation, {Delta}H{sub f} = {minus}27 {+-} 1 kJ/mol for PdSn{sub 4} from Pd and Sn.

• Sponsoring Organization: National Science Foundation, Washington, DC (United States)
• OSTI ID: 479281
• Report Number(s): CONF-951155--; ISBN 1-55899-301-0
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALORIMETRY
COMPOSITE MATERIALS
DIFFUSION
ELECTRONIC EQUIPMENT
EXPERIMENTAL DATA
FOILS
INTERMETALLIC COMPOUNDS
KINETICS
PALLADIUM
PHASE DIAGRAMS
PHASE STUDIES
THERMODYNAMICS
TIN