The role of boron on microstructural and wear behavior of A356/XB alloys produced by mechanical alloying method

In this study, A356/XB alloys (0.25%–2.0% wt. B) have been produced by the mechanical alloying (MA) method, and its microstructure and dry sliding wear performance are investigated. A356 alloy with 1.0% B exhibited remarkable grain sphericity and grain refinement. Moreover, it is observed that the relative density decreased, and the porosity and micro- and macrohardness are increased by the increase in B addition. According to the X-ray diffraction analysis, AlB₂, AlB₁₂, and AlFeB intermetallics are formed in the microstructures of A356/XB alloys due to the sintering process and the mechanochemical reaction during the MA. Moreover, it has been determined that the relative density of A356/XB alloys decreases depending on the B addition, and the relative density of the A356 alloy with 2% B addition has decreased. The lowest wear rate is determined in the A356/1.0B alloy, and the highest wear rate is observed in the A356 alloy.