Measurement of aluminum alloys plasticity under their dynamic and static loading by the Vickers pyramid

Abstract

The paper considers the possibility of assessing the plasticity of aluminum alloys and aluminum matrix composites by the method of quasi‑static and micro‑impact indentation at pre‑impact velocities in the range of 1–3 m/s. It is proposed to use a pyramidal Vickers indenter for testing, which allows creating a constant amount of deformation. The characteristic plasticity values for industrial aluminum alloys and aluminum matrix composites of the Al‑Fe‑Cr system δ=0.83–0.98 are established. The influence of the deformation rate on the dynamicity coefficient Kd, which is the ratio of dynamic and static hardness, is shown. It was found that the increase in Kd for aluminum matrix composites is more significant than for other materials. At the same time, the well‑known expression linking plasticity with other mechanical characteristics: hardness HV and modulus of elasticity E, is not fulfilled for the studied aluminum matrix composites. The difference in the values of δ, calculated based on the parameters of the print and as a function of E/HV, can serve as an additional sign of the atypical behavior of materials during deformation.

Keywords

• indentation
• plasticity
• aluminum
• deformation rate