Asymmetrical Barkhausen Noise of a Hard Milled Surface

Mária Čilliková,Pavel Kejzlar,Robert Čep,Branislav Mičieta,Miroslav Neslušan,Anna Mičietová

doi:10.3390/ma14051293

Mária Čilliková, Pavel Kejzlar + Show 4 more

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https://doi.org/10.3390/ma14051293

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Abstract

This study is focused on the asymmetrical Barkhausen noise emission of a hard milled surface during cyclic magnetisation. The Barkhausen noise is studied as a function of the magnetising voltage and the hard milled surface is compared with a surface after heat treatment. The asymmetry in the Barkhausen noise emission after hard milling occurs due to the typical “sandwich” structure and the different magnetic hardnesses of the different layers beneath the free surface. Furthermore, this asymmetry is also due to the preferential orientation of the matrix in the direction of the cutting speed and magnetostatic fields, which hinder or favour the premagnetising process.

Highlights

IntroductionHard machining (mainly turning and milling) can be used as a substitute for grinding cycles
The presence of a white layer (WL) in such a surface indicates that the WL is a product of the temperature cycle when the hard milled surface is heated over the austenitising temperature, followed by rapid self-cooling, which in turn results in re-hardening of the near-surface layer
The preferential orientation of the near-surface matrix into the cutting speed direction takes a major role in the high magnetic Barkhausen noise (MBN) emission after hard milling; The remarkable asymmetry in the consecutive MBN bursts and the corresponding

Summary

Introduction

Hard machining (mainly turning and milling) can be used as a substitute for grinding cycles. The development of machine tools, as well as process technology, has increased the industrial relevance of hard machining [1]. The mechanism of chip separation during grinding significantly differs from hard machining. For this reason, the state of the surface produced by these competitive operations is completely different. The main distinctions are as follows [2]: (i) a much longer time period during which higher temperatures penetrate beneath the free surface at grinding

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