White-white polymer joints made with different laser absorbing nano fillers: Physical-mechanical features

Carbon, titanium and silver nanoparticles have been added to biomedical grade Ultra High Molecular Weight Poly Ethylene (UHMWPE) for the creation of "white-white" joints welded with a diode laser operating at 970 nm wavelength. The physical and surface features of the nanocomposite sheets, before and after the laser welding process, were measured in terms of surface roughness and wet ability (of distilled water, Simulated Synovial Fluid and human blood). Their adhesion strength and effect of the different nanoparticles on the joint’s physical features have been evaluated by a lap shear test. Experimental results highlight as diode laser energy changes the surface features in a different way depending on filler’s thermal conductivity while bulk features seems to be mainly due to filler size and hence, their dispersion degree inside the polymeric matrix.