Internal friction of capsule-free HIPed porous alumina
Porous alumina were sintered by conventional sintering and capsule-free Hot Isostatic Pressing (HIPing), at temperatures between 800 and 1500 °C under pressures 0.1 MPa or 200 MPa for 1 h or 50 h. Young’s modulus and internal friction of samples were measured by resonance method. The results show that Young’s modulus is mainly dominated by porosity of material. Capsule-free HIPed porous materials have slightly higher Young’s modulus than conventionally sintered ones at the same porosity. Internal friction is governed by both porosity and specific surface area. Capsule-free HIPed porous alumina has lower internal friction coefficient than conventionally sintered ones at the similar porosity or at the similar specific surface area. Enhanced surface-self diffusion under high gas pressure reduces internal friction coefficient, and affects internal friction more than Young’s modulus.
KeywordsPorous alumina Internal friction Capsule-free HIP
Unable to display preview. Download preview PDF.
- 1.K. Ishizaki, S. Okada, T. Fujikawa, A. Takata, U.S. Patent 5,126,103, 30 June 1992Google Scholar
- 3.A. Takata, K. Ishizaki, Y. Kondo, T. Shioura, in Pressure Effects on Materials Processing and Design, ed. by K. Ishizaki, E. Hodge, M. Concannon (Materials Research Society, Pittsburgh, 1992), p.␣133Google Scholar
- 4.Y. Kinemuchi, N. Fusamune, A. Takata, K. Ishizaki, J. Ceramic Soc. Japan 106, 435 (1998)Google Scholar
- 5.A. Rytter, R. Brincker, P.H. Kirkegaard, Fracture & Dynamics, paper No. 37, Department of Building Technology and Structural Engineering, University of Aalborg, Denmark (1992) p. 76Google Scholar