Study on the formation of defects in duralumin forgings

Abstract

The mechanism of forming defects in 2024, 7075 series aluminium alloy forgings has been studied by means of metallography, EDAX, SEM etc. The defects are divided into two types by their appearance: needle-shaped and flake-shaped. The mechanism of them forming is discussed. It has been testified that the defects result from hydrogen or oxide film. The defects can be prevented by controlling the hydrogen content in the melt and keeping oxide film from involving.

Keywords

aluminium alloy / forging / hydrogen embrittlement / oxide film

References

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