J. P. Nobre  A. Morao Dias  R. Gras      

Anales de la Mecánica de la Fractura, nº 13 . 1996 . Pág. 142 -147
Ver (.pdf): Anales13-023

Resumen: With the help of a pendulum machine, we studied the behaviour of a normalized steel when exposed to the impact of alumina a balls. We could associate the normal and tangential impulses with surface deterioration. Experimental studies of single particle impact (SPI) are very useful for the knowledge of metal removal mechanisms in erosive processes. In normal impact experiments, we verified that, within the range of the impact energy used, there wasn 't Iip formation. The impact indentation was identical to the quasi-static one. The average dynamic pressure doesn't seem constant and is higher than the value obtained in quasi-static indentation. On the other hand, in the experiments with sliding friction, there was lip formation with ejection of a small, fragile, oxidized chip, after a certain critical sliding speed. The impact duration and the friction coefficient have a maximum value. This value seems to be related with the critical angle of attack, common in the abrasive and erosive ductile processes.

Localización: Luso, Portugal

Departamento de Engenharia Medinica da Universidade de Coimbra, Polo ll, Pinhal de Marrocos 3030 Coimbra, Portugal
Departamento de Engenharia Medinica da Universidade de Coimbra, Polo ll, Pinhal de Marrocos 3030 Coimbra, Portugal
Laboratoire de Tribologie de 1' Institut Supérieur des Matériaux et de la Construction Mécanique, St. Ouen, France