Residual stress-induced spontaneous microcracking in α-SiC platelet Al2O3 composites
- 43 Downloads
The micromechanical stresses associated with hexagonal (6H) α-SiC platelets within a fine-grained alumina matrix were calculated using an Eshelby approach. The stresses within and around the interface of SiC platelets were determined. Both stresses were found to be strongly dependent on the morphology and the volume fraction of the SiC particles. The morphology effect, however, tended to be limited at aspect ratios ⩾ 10. Owing to anisotropy in the thermal and elastic properties of α-SiC, the residual stresses just outside the inclusion also depended on the position along the SiC/Al2O3 interfaces. The maximum tensile stress was found at the edges of SiC platelets. There were two principal tangential tensile stresses which differed greatly at the edges of disc-shaped inclusions. The results of the stress analysis were consistent with observed differences in microcrack morphology and the resultant reduction of the Young's modulus of the composites.
KeywordsAnisotropy Al2O3 Residual Stress Tensile Stress Elastic Property
Unable to display preview. Download preview PDF.
- 1.G. C. WEI and P. F. BECHER, Am. Ceram. Soc. Bull. 64 (1985) 298.Google Scholar
- 4.H. M. JANG, W. E. RHINE and H. K.BOWEN, ibid. J. Am. Ceram. Soc. 72Google Scholar
- 5.N. CLAUSSEN, in “11th RISO International Symposium on Metallurgy and Materials Science 1990”, edited by J. J. Bentzen, J. B. Bilde-Sorensen, N. Christiansen, A. Horsewell and B. Ralph (Chapman and Hall, London, 1969) p. 1.Google Scholar
- 6.G. SANDERS and M. V. SWAIN, Mater. Forum 14 (1990) 60.Google Scholar
- 8.W. B. JOHNSON, A. S. NAGELBERG and E. BREVAL, ibid. 74 (1991) 2903.Google Scholar
- 9.Y-S CHOU and D. J. GREEN, ibid., submitted.Google Scholar
- 22.Z. LI, PhD thesis, University of Washington, Seattle, WA (1988).Google Scholar
- 29.Y-S CHOU, PhD thesis, The Pennsylvania State University (1992).Google Scholar
- 32.D. P. H. HASSELMAN and J. O. SINGH, Am. Ceram. Soc. Bull. 58 (1979) 856.Google Scholar