| Friction stir processing (FSP) was employed to produce SiO2/AZ31 composites for increase of the hardness of AZ31 matrix. SiO2 particles with sizes of less than 0.2µm were uniformly dispersed into the matrix processed by FSP. As a result, the addition of SiO2 particles resulted in grain refinement of equi-axed ultrafine grains with sizes of less than 1 µm evolved in composite zone. Both the grain refinement and dispersion of SiO2 particles caused hardness of the composites to 90 Hv, which was 1.83 times higher than that of the original alloy. |
full paper (pdf, 1216 Kb)