The Machining of TiA1-Based Intermetallics

  • H. Zhang
  • M. L. H. Wise
  • D. K. Aspinwall
Chapter

Abstract

The sustained high temperature strength of the TiA1-based intermetallics causes severe wear problems with most cutting tool materials due to the heat generated in cutting. The most suitable tool material for turning Ti-48A1-2Nb-2Mn intermetallic was found to be fine grain (0.8 to 1.0 µm) cemented carbide containing 94% WC and 6% Co. The effect of changing cutting parameters and tool geometry on tool life was investigated. Tool life was much more sensitive to feed rate and cutting speed than in the machining of conventional titanium alloys and maximum metal removal rates were much lower. It was found that the tool life could be improved by using negative rake tools, but this was at the expense of surface finish. Tool failure was generally caused by flaking away of the tool edge and a strongly bonded layer, which was confirmed to be workpiece material, was observed on worn areas of the tool. Ti-48A1-2Nb-2Mn is extremely brittle and produces a powdery chip during single point cutting.

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References

  1. 1.
    C.T. LIU and J.O. STIEGLER (1990) Ordered intermetallics; Metals Handbook, Tenth Edition, 2, Properties and Selection: Non-Ferrous Alloys and Special-Purpose Materials, ASM, p. 913–942Google Scholar
  2. 2.
    YOUNG-WON KIM and F.H. FROES (1990) Physical metallurgy of titanium aluminides; Indianapolis, Indiana, Oct. 1–5, 1989, High Temperature Aluminides and IntermetallicsGoogle Scholar
  3. 3.
    D.M. DIMIDUK, D.B. MIRACLE and C.H WARD (1992) Development of intermetallic materials for aerospace systems; Materials Science and Technology, 8, p. 367–375Google Scholar
  4. 4.
    YOUNG-WON KIM and D.M. DIMIDUK (1991) Progress in the understanding of gamma titanium aluminides; JOM, 43, No. 8, p. 40–47Google Scholar
  5. 5.
    M. YAMAGUCHI (1992) High temperature intermetallics — with particular emphasis on TiAI; Materials Science and Technology, 8, p. 299–307Google Scholar
  6. 6.
    J.F. KAHLES, M FIELD, D. EVLON and F.H. FROES (1985) Machining of titanium alloys; J. Metals, 37, p. 27–35Google Scholar
  7. 7.
    H.E. CHANDLER (1989) Machining of Reactive Metals; Metals Handbook, Ninth Edition, 16, Machining, ASM, p. 844–853Google Scholar
  8. 8.
    A.R. MACHADO and J. WALLBANK (1990) Machining of titanium and its alloys — a review; Proc. Inst. Engrs., 204, p. 53–60Google Scholar
  9. 9.
    J.W. SEARS (1992) Clean melting and processing via plasma cold-hearth and cold-wall induction; The Processing, Properties, and Applications of Metallic and Ceramic Materials, 1, MCE Publications Ltd., p. 119–133Google Scholar
  10. 11.
    J.L. HAU-BRACAMONTE and M.L.H. WISE (1982) Cementite particle solution and machinabilty of low-carbon steels; Metals Technol., 9, p. 454–464CrossRefGoogle Scholar
  11. 12.
    K.J.A. BROOKES (1992) World Directory and Handbook of hardmetals and hard materials; Fifth Edition, International Carbide DataGoogle Scholar
  12. 13.
    P.A. DEARNLEY and A.N. GREARSON (1986) Evaluation of principle wear mechanisms of cemented carbides and ceramics used for machining titanium alloy IMI318; Mater. Sci. Technol., 2, p. 47–58CrossRefGoogle Scholar
  13. 14.
    E.M. TRENT (1991) Metal cutting; Third Edition, Butterworths, LondonGoogle Scholar
  14. 16.
    M.J. DONACHIE (1988) Titanium-A Technical Guide; ASM InternationalGoogle Scholar
  15. 18.
    P.D. HARTUNG and B.M. KRAMER (1982) Tool wear in titanium machining, Annals of CIRP, 31, p. 75–80CrossRefGoogle Scholar
  16. 20.
    M.C. SHAW (1965) The assessment of machinability; ISI Special Report No. 94, “Machinability”; Iron and Steel Inst. London, p. 1–9Google Scholar
  17. 21.
    R. KOMANDURI (1983) Evaluation of carbides and new cutting geometry for machining titanium alloys; Wear, 77, p. 113–123Google Scholar
  18. 22.
    H. NOTOYA et al (1990) The effects of tool materials on machining of commercially pure titanium; J. Jap. Inst. Metals, 54, p. 596–602Google Scholar
  19. 23.
    C.A. BROOKES (1991) Turning aerospace titanium alloys; Ind. Diamond Rev., 51, p. 89–93Google Scholar

Copyright information

© Department of Mechanical Engineering University of Manchester Institute of Science and Technology 1993

Authors and Affiliations

  • H. Zhang
    • 1
  • M. L. H. Wise
    • 1
  • D. K. Aspinwall
    • 1
  1. 1.University of BirminghamUK

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