Microcosmic Mechanism of Short Fatigue Crack Propagation in High Strength Aluminum Alloy

  • Pu Li
Keywords: High-Strength Aluminum Alloy, Fatigue Fracture, Micro-mechanism, Microscope Research

Abstract

With the rapid development of modern science and technology, the application of microscope technology has
also matured and has been widely used in the observation and research of metal properties. Because
high-strength aluminum alloys have corrosion resistance and high fracture toughness, the performance of the
alloy can be checked by performing a microscopic fatigue test under a polarized light microscope. However,
fatigue and fracture of high-strength aluminum alloys have become the biggest drawbacks that restrict its
development. Therefore, it is necessary to carry out research on the micro-mechanism of short-fatigue crack
growth of high-strength aluminum alloys. The purpose of this article is to solve the micro-mechanism of fatigue
fracture of high-strength aluminum alloys. Through the study of the micro-mechanism of short fatigue crack
growth of high-strength aluminum alloys, the electron backscatter diffraction technology is used to build a
universal model of fatigue life reliability and fatigue performance reliability. Microscope experiments were
performed on the microscope, and the results of fatigue experiments, fatigue crack growth rate tests, and fracture
toughness tests were analyzed to obtain the relationship of fatigue fracture propagation of high-strength
aluminum alloys. The research results show that the study of the micro-mechanism of short fatigue crack growth
of this high-strength aluminum alloy can obtain the relationship between the grain orientation of adjacent grains
and crack growth following the crystal plastic deformation mechanism of the crack tip. When the effective slip
surface between two adjacent grains cannot form a 45-degree double-sided angle, the crack cannot directly pass
through the grain boundary, and tends to propagate along the grain, which will cause fatigue fracture.

Published
2020-02-01