Fretting Fatigue Behaviour of Alloy Steel in the Very High Cycle Region

Yoshinobu Shimamura,Reo Kasahara,Toru Yagasaki,Keiichiro Tohgo,Tomoyuki Fujii,Hitoshi Ishii,Soichiro Sumida,T Palin-Luc,F Morel,A Carpinteri

doi:10.1051/matecconf/201930018002

Yoshinobu Shimamura, Reo Kasahara + Show 8 more

Open Access

https://doi.org/10.1051/matecconf/201930018002

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Abstract

It is well known that fretting fatigue strength is much lower than the fatigue strength of smooth specimens and the fatigue limit disappears. Many studies on fretting fatigue have been reported but most of the studies have not cover fatigue properties in the very high cycle regime more than 107 cycles. In this study, an accelerated fretting fatigue testing method was developed by using an ultrasonic torsional fatigue testing machine with a clamping fretting pad. Fretting fatigue tests of CrMo steel were conducted by using the developed method. Test results showed that fretting fatigue failure occurs in the very high cycle region.

Highlights

Accelerated fatigue testing machines are required in order to investigate fatigue properties in the very high cycle regime within practical testing periods, and an ultrasonic fatigue testing method using a piezoelectric oscillator is prospective one
A fatigue crack initiated from the surface of a specimen during a torsional fatigue test because the maximum shear stress was applied to the surface
A new accelerated fretting fatigue testing method was developed by using an ultrasonic torsional fatigue testing machine with a clamping fretting pad

Summary

Introduction

Accelerated fatigue testing machines are required in order to investigate fatigue properties in the very high cycle regime within practical testing periods, and an ultrasonic fatigue testing method using a piezoelectric oscillator is prospective one. Authors have developed an ultrasonic torsional fatigue testing machine and investigated fatigue properties of carburized steels without internal fracture [1]. Torsional loading is more suitable than axial loading for investigating fatigue properties of case hardening materials such as carburized steels. A new accelerated fretting fatigue testing method was developed by using an ultrasonic torsional fatigue testing machine with a clamping fretting pad.

Experimental

Results and discussion

Conclusions