Effect of different PCA types on morphology, physical, thermal and mechanical properties of AA2024-B4C composites

Abstract

In this study, the effect of various process control agents (PCAs), including Methanol, Ethanol, Stearic acid, and Zinc stearate, on the properties of AA2024-B4C composite powders during the milling was investigated. Through comprehensive analyses encompassing morphological imaging, EDS assessments, particle size measurements, hardness evaluations, apparent density calculations, XRD, TGA examinations, and subsequent hardness and tensile strength tests on bulk samples derived from these composite powders, intriguing findings emerged. The employment of methanol as a PCA manifested an 85% reduction in the average particle size, decreasing from 220 mu m (initial powder size) to 35 mu m after 5 h of milling. In contrast, the use of zinc stearate resulted in a more conservative 21% reduction, with an average particle size of 174 mu m. Notably, methanol usage resulted in superior hardness (144.5 HB) and tensile strength (262 MPa) compared to zinc stearate, which yielded lower values (107.8 HB and 204.5 MPa).