Paper number 1193
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FATIGUE LIFE BEHAVIOUR OF SNPBAG/NITI COMPOSITE |
S. Trombert1, J. Chazelas1, M. Lahaye2, Olivier Fouassier2, J.F. Silvain2
1THOMSON-CSF†/ RCM, La Clef de St Pierre, F-78852 - ELANCOURT(FRANCE)
2Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB) - CNRS, Université de Bordeaux I, 87 Av. du Dr. A. Schweitzer, F-33608 - PESSAC (FRANCE)
| Summary | Uncoated and copper electroless coated fine NiTi superelastic particles have been incorporated into liquid SnPbAg matrix. The wettability of the Cu coating by the molten alloy was determined with a wetting balance. The composite interfaces have been investigated by Auger Electron Spectroscopy. Uncoated NiTi reacted with the matrix to form Ni-Sn intermetallics, whereas the Cu layer of coated particles behaved as a sacrificial layer, leading to a small interfacial zone containing neither Cu-Sn nor Ni-Sn intermetallics. The mechanical characterisation of Cu-coated NiTi/SnPbAg composites shows a reinforcement of the composite material compared to the monolithic matrix, and also an unusual increase of the elongation at rupture. This results can be interpreted with the superelastic properties of the NiTi SMA particles. |
Keywords | tin lead silver alloy, nickel titanium, superelasticity, metal matrix composite, electroless copper coating, interfacial study. |