Abstract
Mechanisms of surface and sub-surface wear damage in MgO single crystals were investigated by scratching with two sintered alumina sliders, having tip radii of 60 and 120μm, using a simple scratching apparatus in a controlled atmosphere. The degree of surface and sub-surface cracking is dependent on the shape of the slider and the normal contact load, which are related to the penetration into the crystal. The chevron crack on the (001) plane in the [100] sliding direction consists of cracks intersecting at an angle of 90°, and with a spread angle of about 120°, and the normal crack. The nature of the sub-surface damage is investigated; a parallel crack develops in front of the slider and an oblique crack propagates towards the front of the slider. Then an internal normal crack is formed between the oblique crack and the parallel crack. In the [110] direction, the oblique crack initiates from the top of the normal crack under the surface, and the parallel crack continues from the oblique crack. This wear damage is explained by the dislocation interactions occurring due to the distribution of resolved shear stresses during sliding. The wear caused by the chevron crack is a factor of 10 higher than that with plastic flow. Internal cracks do not have a direct influence on the increase of wear.
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F. P. BowdenandC. A. Brookes,Proc. Roy. Soc. Land. A-295 (1966) 244.
C. A. Brookes, J. B. O'neill andB. A. Redfern,ibid. A-322 (1971) 73.
A. S. Keh.J. C. M. Li andY. T. Chou,Acta Met. 7 (1959) 694.
B. H. Kear, A. Taylor andP. L. Pratt,Phil Mag. 4 (1959) 665.
M. S. Stucke andA. S. Wronski,J. Mater. Sci. 9 (1974) 911.
R. J. Stokes, T. L. Johnston andC. H. Li,Phil. Mag. 3 (1958) 718.
Idem, ibid. 4 (1959) 920.
Idem, ibid. 6 (1960) 9.
T. G. Langdon andJ. A. Pask, “High Temperature Oxides-Part 3, MgO, A12O3, BeO Ceramics: Fabrication, Characterization and Properties”, edited by Allen M. Alper (Academic Press, 1970).
A. H. Cottrell,Trans. Amer. Inst. Min. (Metall.)Eng. 212 (1958) 192.
R. P. Steijn,Wear 7 (1964) 48.
Idem, J. Appl. Phys. 34 (1963) 419.
F. P. Bowden andA. E. Hanwell,Proc. Roy. Soc. Land. A-295 (1966) 233.
D. H. Buckley, “Friction, Wear, and Lubrication in Vacuum”, NASA SP-277 (1977).
T. Sugita andH. Yasunaga,Wear 40 (1976) 121.
T. Sugita, K. Suzuki andS. Kinoshita,ibid. 45 (1977) 57.
K. F. Dufrane andW. A. Glasser, NASA CR72530, Battelle Memorial Institute, Columbus Laboratories (1969).
J. O. Smith andC. K. Liu,J. Appl. Mech., Trans. ASME 75 (1953) 157.
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Sugita, T., Hasegawa, T. Wear damage of MgO single crystals. J Mater Sci 13, 1471–1479 (1978). https://doi.org/10.1007/BF00553201
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DOI: https://doi.org/10.1007/BF00553201