Production of parcelic reinforced composite materials with aluminum alloy chemical recycling using hot extrusion method

In this study, B4C powders were added to Al7050 chips in different proportions (5, 10 and 15% by weight) and the mixture was obtained in a ball mill at 200 rpm for 5 hours. The mixtures were compacted unilaterally at 550oC under 600 MPa pressure to produce billet samples with a diameter of 25 mm. The produced billets were extruded at a temperature of 550oC at different extrusion rates using a vertical axis hydraulic press with a capacity of 120 tons and 6 mm and 12 mm diameter rod-shaped samples were produced. Metallographic investigations, XRD analyzes, density measurements, hardness measurements, compression and tensile tests were used to determine the effects of extrusion rate and B4C amount on the mechanical and microstructural properties of the produced samples. According to the results, the dimensional reduction of Al7050 chips was determined with the increase of B4C amount in ball milling process. In addition, relative density values above 90% were obtained in the samples having both extrusion rates. As a result of the microstructural observations, the agglomerations in the chip boundaries with increase in the amount of particles were detected. These agglomerations led to structural defects. According to XRD results, no reaction products were found in the structure. The maximum hardness value was obtained in samples containing 5% B4C. The hardness values obtained for samples with 6 mm and 12 mm diameter were 76.4 HV and 75.3 HV respectively. In both sample types, the added B4C particles reduced the maximum tensile strength (UTS) and elongation. It was found that the samples with a diameter of 6 mm have higher tensile strength values than samples with a diameter of 12 mm. The maximum tensile strengths for samples with diameters of 6 mm and 12 mm without B4C are 286 MPa and 190 MPa, respectively. The compressive strength of the samples decreased with the increase in the amount of B4C.