Ultrasonic Evaluation of Spray-Dried Ceramic Powders During Compaction

  • Martin P. Jones
  • Gerald V. Blessing


There is a growing need to nondestructively evaluate (NDE) compacted ceramic powder parts in the green (unfired) state. In many cases, the quality of the final sintered product is determined by the quality of the starting powder and its homogeneity after compaction. If inferior compacts could be detected, it would be possible to reject them prior to further costly processing stages [1]. Some flaws can occur during subsequent sintering [2], or machining [3], or polishing [4], etc. The quality control of ceramics can be enhanced by applying NDE methods at several stages of processing to narrow the possible origins of a particular problem.


Wave Amplitude Wave Speed Ultrasonic Wave Ceramic Powder Alumina Powder 
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  1. 1.
    M.P. Jones, G.V. Blessing, and C.R. Robbins, Dry-Coupled Ultrasonic Elasticity Measurements of Sintered Ceramics and Their Green States, Mater. Eval., 44:859 (1986).Google Scholar
  2. 2.
    F.F. Lange, Structural Ceramics: A Question of Fabrication Reliability, J. Mater. for Energy Systems, 6:107 (1984).CrossRefGoogle Scholar
  3. 3.
    K.K. Smyth and M.B. Magida, Dynamic Fatigue of a Machinable Glass Ceramic, J. Am. Ceram. Soc., 66:500 (1983).CrossRefGoogle Scholar
  4. 4.
    J.J. Mecholsky, S.W. Freiman, and R.W. Rice, Effect of Grinding on Flaw Geometry and Fracture of Glass, J. Am. Ceram. Soc., 60:114 (1977).CrossRefGoogle Scholar
  5. 5.
    A. Nagarajan, Ultrasonic Study of Elasticity-Porosity Relationship in Polycrystalline Alumina, J. App. Phys., 42:3693 (1971).CrossRefGoogle Scholar
  6. 6.
    R.M. Arons and D.S. Kupperman, Use of Sound-Velocity Measurements to Evaluate the Effect of Hot Isostatic Pressing on the Porosity of Ceramic Solids, Mater. Eval., 40:1076 (1982).Google Scholar
  7. 7.
    J.J. Tien, B.T. Khuri-Yakub, O.S. Kino, D.B. Marshall, and A.G. Evans, Surface Acoustic Wave Measurements of Surface Cracks in Ceramics, J. Nondestructive Eval., 2:219 (1981).CrossRefGoogle Scholar
  8. 8.
    W. Kreher, J. Ranachowski, and F. Rejmund, Ultrasonic Waves in Porous Ceramics with Non-Spherical Holes, Ultrasonics, 15:70 (1977).CrossRefGoogle Scholar
  9. 9.
    D.S. Kupperman and H.B. Karplus, Ultrasonic Wave Propagation Characteristics of Green Ceramics, Ceram. Bull., 63:1505 (1984).Google Scholar
  10. 10.
    M.P. Jones and G.V. Blessing, Real-Time Ultrasonic Evaluation of Green State Ceramic Powders During Compaction, Nondestructive Testing Communications, 2(5), (1986).Google Scholar
  11. 11.
    C.A. Bruch, Problems in Die-Pressing Submicron Size Alumina Powder, Ceram. Age, 10:44 (1967).Google Scholar
  12. 12.
    F.F. Lange, Sinterability of Agglomerated Powders, J. Am. Ceram. Soc., 67:83 (1984).CrossRefGoogle Scholar
  13. 13.
    H. Kolsky, “Stress Waves in Solids,” Dover Pub., New York (1963).Google Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Martin P. Jones
    • 1
  • Gerald V. Blessing
    • 2
  1. 1.Materials Science DepartmentThe Johns Hopkins UniversityBaltimoreUSA
  2. 2.Ultrasonic Standards GroupNational Bureau of StandardsGaithersburgUSA

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