Dry Sliding Wear Behavior of Composite Materials Fabricated by Powder Metallurgy

Aluminum matrix composites (AlMCs) were fabricated by powder metallurgy route. Two different ceramic oxides as (SiO2 and TiO2) were incorporated into aluminum matrix with different weight percentages at (3, 6, 9 and 12 wt. %) to produce aluminum matrix composites (AlMCs). There are many applications for aluminum matrix composites, such as connecting rods, vehicle parts and aerospace. The samples for this work were prepared by the following stages. The first stage is preparing aluminum powder (as a matrix) having 100 µm particle size, while SiO2, TiO2 as additive materials have about 150 µm in a particle size. The second stage is mixing the chosen powders using a planetary mixer. The third stage is a compacting process by a hydraulic unidirectional press to produce green compacts. Afterward, the samples were sintered at 480°C for 4 hours using an electrical furnace supplied with argon gas. The microstructure of the samples was examined using optical microscope (OM), the hardness of the samples was tested by Rockwell hardness apparatus. Wear test was carried out using pin-on-disc technique by changing the applied loads at a constant sliding time (10 min). Also, the physical properties, like porosity and density for the specimens after sintering were defined. The obtained results manifested that the improving in the wear resistance and hardness for Al/TiO2 is more than for Al/SiO2. And, the microstructure examination revealed that SiO2 and TiO2 are homogeneously distributed in Al matrix. Also, the results evinced an improvement in density and porosity for the manufactured composite material.