The structure and properties of PM composite materials based on EN AW-2124 aluminum alloy reinforced with the BN or Al2O3 ceramic particles

Investigations of composite materials based on EN AW-2124 aluminum alloy reinforced with the BN or Al2O3 particles with various weight ratios of 5, 10 and 15% are presented. Powders of the starting materials were mixed in the laboratory vibratory ball mill to acquire the uniform distribution of reinforcement particles in the matrix material. The components were initially compacted at cold state in a die with the diameter of Ø 26 mm in the laboratory vertical unidirectional press—with a capacity of 350 kN. The obtained P/M compacts were heated to a temperature of 480/500 °C and finally extruded—with the extrusion pressure of 500 kN. Bars with a diameter of 8 mm were obtained as the end product. Based on the microstructural examinations of the obtained composite materials, the uniform distribution of the reinforcing particles in the aluminum matrix was revealed. Hardness tests, static tensile tests and the compressive tests made it possible to demonstrate that all these properties change along with the reinforcing particles concentration change. As an example, hardness increased from 89 HV1 for the material without the reinforcing phase to 123 HV1 for 15% of BN, and the ultimate compressive strength decreases along with the increase of the reinforcing phase fraction from 667 MPa for 5% to 472 MPa for 15% of BN.