Room temperature wear performance and mechanical properties of hot extruded ultrafine-grained Al5083-5 wt%B4C-Al2024 tri-modal composites

Abstract

In this paper, the mechanical properties and wear performance of Al5083-5 wt%B4C-Al2024 tri-modal composites at room temperature has been discussed. Al2024 alloy powders were added to mechanically milled Al5083-5 wt%B4C powders as coarse grains and the samples consolidated using the hot press and hot extrusion techniques. Results indicated that by adding Al2024 coarse grains, tensile strength of Al5083-5 wt%B4C composite decreased up to 35% from 508 MPa to 327 MPa however, ductility increased from 2.8 to 5%. Moreover, by adding 50 wt% of Al2024 coarse grains, hardness decreased from 355 to 288 HV which had a significant role on the room temperature wear performance of the tri-modal samples and wear rate increased from 3.5 × 10−6 to 4.7 × 10−6 (mm3 m−1). It seemed that room temperature wear performance of Al5083-5 wt%B4C-Al2024 composites is directly dependent to the hardness and the weight percentage of the Al2024 coarse grains.