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Publication Citation: White layers and thermal modeling of hard turned surfaces

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Author(s): Y K. Chou; Christopher J. Evans;
Title: White layers and thermal modeling of hard turned surfaces
Published: January 01, 1998
Abstract: White layers in hard turned surfaces are identified, characterized and measured as a function of tool flank wear and cutting speed. White layer depth progressively increases with flank wear. It also increases with speed, but approaches an asymptote. A thermal model based on Jaeger? s moving heat source problems (J.C. Jaeger, Moving source of heat and the temperature at sliding contacts, in: Proceedings of the Royal Society, NSW, vol. 56, pp. 203-224) is applied to simulate the temperature field in machined surfaces and to estimate white layer depth in terms of the penetration depth for a given critical temperature. The analysis shows good agreement with the trend in experimental results. White layer formation seems to be dominantly a thermal process involving phase transformation of the steel, possibly plastic strain activated; flank wear land rubbing may be a primary heat source for white layer formation. A strong material dependence of surface alteration is also observed. Published by Elsevier Science Ltd.
Citation: International Journal of machine Tools and Manufacture
Volume: 39
Pages: pp. 1863 - 1881
Keywords: Hard turning;phase transformation;surface integrity;White layer
Research Areas: Metrology and Standards for Manufacturing Processes