Richard Kouitat Njiwa

Abstract:

Steel plates have been coated by Al-based quasicrystal obtained by atomization from the liquid state and sprayed using a high-velocity oxygen-fuel flame torch. Static and sliding contact experiments were carried out in order to assess on the one hand the mechanical properties of the quasicrystal and on the other hand the friction and related properties such as wear and resistance to scratch. Besides these conventional properties, indentation experiments reveal the porous nature of the thick coating. Scratch test experiments pinpoint the low elastic recovery of the sample (despite a low plastic deformation at high loads). Pin on disc experiments reveals the abrasive nature of the coating.<br />In the end, the friction properties of this type of coating appear excellent in comparison to many state-of-the-art surface layers. The talk will summarize such findings and will compare them to solutions most frequently used in mechanical devices.