Maximization of Silica Loading in Ball-Milled Composite Powders for HVOF-SprayedMulti-scale Polymer/Silica Composite Coatings

摘要

The high velocity oxy-fuel (HVOF) combustion spray technique has been shown previously to be an excellentsolution for depositing crystalline matrix nano-reinforced polymer coatings. Dense polymer coatings can beproduced by controlling both the particle dwell time in the HVOF jet and through substrate thermal management.In composite materials, it is often desirable to incorporate the maximum amount of reinforcing material into thepolymer matrix to achieve optimum mechanical properties. The experiments described here were performed todetermine the maximum amount of different scales of silica particles that could be incorporated into a nylon 11matrix and the time required to do so. Ashing results indicated a maximum amount of silica that can beincorporated. Also, the maximum level of silica incorporation occurs in a shorter time than previously believed.Microscopy, however, indicated that other physical changes continued to occur within the powders when ballmilling was allowed to continue beyond this time.