6533b831fe1ef96bd1298179

RESEARCH PRODUCT

Modelling of laser beam texturing process: experimental and numerical approaches

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The aim of this work is to reache a better control of the laser beam surface texturing process on three materials: 304L, TA6V and AA6056 alloys. For this purpose, two complementary methods, experimental and numerical modelling, have been used. As a result of the experimental design approach, it was observed that the laser surface texturing process of 304L and TA6V alloys is strongly influenced by the pulse energy and frequency. In order to obtain a surface roughness Sa < 5 µm for the highest possible productivity it is necessary to work with an energy of 5 mJ and a frequency ranging between 10 and 12 kHz. Unfortunately, for aluminium alloy AA6056, it is necessary to make a choice between having a good surface quality and having a high productivity. Numerical simulations of the coupled phenomena (heat transfer-hydrodynamics-mechanics) complete the experimental results. They show that the existence of a strong recoil pressure generates a strong movement of liquid towards the edges of the crater. This movement continues even after the end of the laser pulse due to the inertial effect. Since the liquid displacement is more significant in case of AA6056 than in case of 304L and TA6V, there is a more significant pad formation around the impact area of aluminium samples. This has a negative influence on surface roughness. In this case, in order to minimize the surface roughness, it is necessary to assure the best compromise which favours the vaporization in order to decrease the thickness of the melted layer and optimizes the covering rate of the impacts. In conclusion, the laser beam can successfully be used in metal surface texturing process.