Study on mechanical properties and hydrogen embrittlement susceptibility of 7075 aluminium alloy

Abstract

The mechanical properties and hydrogen embrittlement susceptibility of 7075 aluminium alloy were studied by means of cathodic H permeation, hydrogen determinator, slow strain rate test (SSRT), energy dispersive X-ray spectroscopy (EDS) and scanning electron microscope (SEM). The results showed that both before and after hydrogen charging, the strength and other properties all have double peaks for the examined alloys, and it was of excellent performance such as high strength and low hydrogen enbrittlement susceptibility under the second aging peak. Mg segregated at grain boundary during aging process, and there may exist Mg–H interaction during the hydrogen charging process, which played a significant role in hydrogen embrittlement.

Keywords

Hydrogen embrittlement Mechanical properties Mg–H interaction Aluminium alloy

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