J. Phys. IV France 01 (1991) C7-111-C7-116
LASER MELTING TREATMENT BY OVERLAPPING PASSES OF PREHEATED NICKEL ELECTRODEPOSITED COATINGS ON Al-Si ALLOYD. PANTELIS1, A. HOUNDRI2, S. POLYMENIS2 and Y. CHRYSSOULAKIS2
1 Laboratory MSS/MAT, URA CNRS n° 850, Ecole Centrale de Paris, Grande Voie des Vignes, F-92295 Châtenay-Malabry cedex, France
2 Laboratory of Physical Chemistry and Applied Electrochemistry, National Technical University of Athens, 9 Iroon Polychniou Str., GR-15773 Zografou, Athens, Greece
Microstructure improvements of a Nickel electrodeposited Al-Si alloy were studied after high power laser melting treatment through a single pass or partially overlapping successive adjacent passes. In some cases laser melting treatment was preceded by a 5-hours heating of the specimens at 500°C in an Argon atmosphere furnace. Best results concerning microhardness, microstructural homogeneity, porosity elimination as well as adhesion of the nickel coating on the Al-Si alloy were achieved when the specimens were first subjected to heating at 500°C in an Argon atmosphere furnace for 5 hours and then submitted to a laser melting treatment through successive adjacent laser passes with an overlapping rate of 70%.
© EDP Sciences 1991