NDTnet 1998 Aug, Vol.3 No.8

Abstract

Acoustic emission technique (AET) is widely used for characterising different deformation and fracture processes in materials and technical constructions. One of the new perspective areas is the AE application for wear and contact fatigue observation. Works in this area have been made above all in Japan and USA^1,2,3. The aim of this work is to show diagnostic possibilities of AET in the area of contact fatigue.

At contact loading evaluation it is very important the exact separation of the individual stages of material surface damage. In the present time we try to substitute the classic way of measurement with vibration sensors by AET. In the paper are sumarised and discussed experimental results of AET utilisation in this area. The changes arising on material surface at course of its contact loading and responses of these changes in acoustic emission signals are shown. There is described experiment arrangement, test centre, measuring equipment itself On examples of experimental measured results are explained advantages of AE signals detection in dependence on time. Different types of the amplitude distribution of AE signals and other types of signal characteristics for basic types of steels and grey cast iron with heat treated surfaces are shown.

From acquainted results is obvious that observation of material tests on contact fatigue by AET has indisputable advantages. The results proved the acoustic emission technique enables reliable recognition of running-in period, stabilised run and very exact definition of origin stage of surface damaging, leading to the pitting. It is proposed direction of AE equipment utilisation not only in research area, but the acoustic emission technique may be successfully used even in industrial practice.

L i t e r a t u r e:
1. Yoshioka, T, Minoru, T: Lubrication Engineering, 1995, 51, (1), 41-44.
2. Yoshioka, T: Lubrication Engineering, 1993, 49, (4),303-308.
3. Klamecki B.E., Hanchi,J.: Journal of Tribology, 1990, 112, 469-476

The contribution is elaborated in frame of the GA CR complex program No. 101/96/K264 Limit states of structural materials with non-standard testing methods utilisation.

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

Publication Contact:
7th ECNDT, Park Alle 345, DK-2605 Broendby, Denmark, Fax: +45 46 26 70 11, Email: 101373.3414@compuserve.com