Aerospace Manufacturing Technology Center (AMTC), National Research Council of Canada (NRC), Canada
Associate editor: J. C. Outeiro
*Corresponding author: [email protected]
Creative Commons License
Surface integrity is one of the most critical output of a machining operation. It has significant impact on the safety, performance, and fatigue life of aerospace components subjected to dynamic loads in harsh environments. The typical aspects of machining-induced integrity including residual stresses, surface roughness and defects, microhardness, near-surface microstructure modification, dynamic recrystallisation and grain refinement are discussed and correlated to the variables of machining system. Special attention is paid to how to control the machining-induced residual stresses by optimizing the cutting parameters, tool geometry, and the cooling strategy. Post-processing options, such as shot peening, burnishing and laser-assisted surface treatment are discussed as means for mitigating induced surface defects and for further improving surface integrity.
The fundamental aspects of residual stress formation during cutting are discussed in relation to: (a) the contribution of thermal and mechanical loads and (b) the effect of the coupling of thermal load and phase transformation. In addition to its effect on fatigue life reduction, the effect of machining-induced residual stresses on the distortion of thin-walled aerospace components is assessed in comparison with the magnitude of distortion produced by the bulk stresses. An overview of the effect of cryogenic cooling strategy of selected difficult-to-machine materials, aerospace alloys, and lightweight materials on machining-induced residual stresses is presented and compared to dry, minimum quantity lubrication, and flood cooling.
Surface integrity, aerospace materials, functional performance and life, Inconel 718, manufacturing processes
23 minutes video
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H. Attia and B. Shi, 2022, « Surface integrity in machining aerospace materials, and its impact on functional performance», Knowledge and Skills, ISSN 2800-2083, Materials Engineering, 020003, https://doi.org/10.53229/k.and.s.2021.020003
Surface integrity in machining aerospace materials, and its impact on functional performance
presented by Pr. Helmi Attia
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