Fracture assessment of PMMA/Si kitchen sinks made from acrylic casting dispersion

Acrylic casting dispersion is used to fabricate kitchen sinks made of PMMA/Si which stands for poly-methyl methacrylate mixed with a fine dispersion of silica. The composite is suited for sanitary wares that are subjected to severe temperatures, giving rise to high thermal stresses. This leads to failure by cracking in the region near the drain hole. Such conditions are investigated by determining the mechanical and fracture properties for two different chemical compositions of PMMA. They are referred to by trade marks from ICI as Asterite and Amatis. Data are obtained for temperatures from 0 to 95 °. Extensometry data are also obtained to the thermal stresses around the drain hole subjected to alternating flow of cold and hot water. Critical crack lengths are determined from the critical stress intensity factor and maximum local tensile stresses based on measured data. They are estimated to be 1.5 mm and 4.0 mm, respectively, for the Asterite and Amatis composites. These results confirm with practice where the cracking of the former was observed while the latter did not crack.