Effect of External Pressure on the Microstructure and Mechanical Properties of In Situ (ZrB2+Al2O3/Al3Zr)/6016 Nanocomposites

In this study, effect of external pressure on the microstructure and mechanical properties of in situ (ZrB2+Al2O3/Al3Zr)/6016 composites, synthesized under electromagnetic field, is investigated using scanning electron microscopy, X-ray diffraction and tensile testing. It is found that the application of 0.5MPa external pressure can promote uniformity in shape and slight decrease in alpha-Al grain size due to pressure-assisted faster solidification rate, and thus results in strengthening of both the 6016 alloy and in situ (ZrB2+Al2O3/Al3Zr)/6016 nanocomposite. It is also found that the external pressure can inhibit the growth of in situ reinforcement particles present in (ZrB2+Al2O3/Al3Zr)/6016 nanocomposite, restricting their size to lower aspect ratios. The improved strengthening of the composite matrix contributes to the simultaneously higher yield strength (YS), ultimate tensile strength (UTS), %elongation and hardness. The work hardening rate and improvement in mechanical properties are discussed in terms of reinforcement particles' size and morphology of tensile fracture.

Automated summary

In this study, the effect of external pressure on the microstructure and mechanical properties of in situ (ZrB2+Al2O3/Al3Zr)/6016 composites synthesized under an electromagnetic field was investigated. It was found that the application of external pressure can lead to improved uniformity, reduced grain size, and inhibited growth of reinforcement particles, resulting in enhanced strength and hardness of the composites.