Roughness Influence on Initiation of Fretting Fatigue Scar of Ti-6Al-4V Alloy

9th International Conference on Tribology

Capitanu, L.^1 ; Badita, L.L.^2 ; Florescu, V.^3 ; Tiganesteanu, C.^1

Institute of Solid Mechanics, Romanian Academy, Bucharest

010141, Romania^1

National Institute of Research, Development for Mechatronics and Measurement Technique, Bucharest

021631, Romania^2

University of Civil Engineering, Bucharest

020396, Romania^3

关键词: Contact surface;    Experimental conditions;    Fretting damage;    Fretting fatigues;    Fretting wear;    Friction coefficients;    Ti-6Al-4V alloy;    Time evolutions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/295/1/012022/pdf
DOI  :  10.1088/1757-899X/295/1/012022

来源: IOP

【 摘 要 】

This paper reports on the experimental studies undertaken to detect the early stage when appears the fretting wear of the Ti-6Al-4V alloy used for the hip prostheses. Wear is a critical aspect for estimating the fretting fatigue. Studies were performed on samples of special shape, in order to be able to study the influence of in contact surfaces roughness on the durability to fretting. Fretting buffers, with roughnesses Raof the contact surface of 0.015 and 0.045 μm, and Ti-6Al-4V samples with roughnesses Ra= 0.045 μm, Ra= 0.075 μm and Ra= 0.19 μm, were used. Testing periods of 3 seconds, 1 minute and 5 minutes were selected to capture the moment of the fretting scar appearance, long before these initiate the eventual fretting cracking. Simultaneously with fretting wear of the surface, the friction coefficient was also measured. From the in time evolution determinations of the fretting wear, it resulted that, under the experimental conditions used, the minimum wear occurs at a certain value of the roughness and not at the minimum roughness. Surprisingly, the minimum friction coefficient does not coincide with the minimum fretting wear.