- Solid solution strengthening of the FCC (face centered cubic) continuous (gamma)-Ni matrix;
- Precipitation hardening by ordered, coherent intermetallics such as gamma’-Ni3(Al, Ti) or gamma’’-Ni3Nb. Gamma’ is a coherently precipitating phase: the crystal planes of the precipitates are in sync with the gamma matrix with an ordered FCC crystal structure. These phases are extremely stable and show only low driving force for coarsening due to their low lattice mismatch.
Processing of superalloys by SLM
- the shrinkage brittleness theory [3-5],
- the strain theory [6-8],
- the generalized theory [9-12],
- and the technological strength theory [13-15].
- Tmax=the temperature where liquid is confined within the solidification structure
- Tmin=the temperature where the boundary liquid is partially or completely solidified and the material recovers its ductility.
Mechanically, the ductility of the material is essentially zero over this temperature range and susceptible to cracking.
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[2b] LIN, J. C. LIPPOLD AND W. A. BAESLACK, An Evaluation of Heat-Affected Zone Liquation Cracking Susceptibility, Part I: Development of a Method for Quantification, WELDING RESEARCH SUPPLEMENT I 135-s, 1993
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 Bishop, H. F., Ackerlind, C. E., and Pellini, W. S. 1952. Metallurgy and mechanics of hot tearing. Trans. American Foundrymans Society 60:818-833.
 Borland, J. C , and Younger, R. N. 1960. Some aspects of cracking in welded Cr-Ni austenitic steels. British Welding Journal 6(1):9^16.
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 Transgranular liquation cracking of grains in the semi-solid state S. Karagadde, P.D. Lee, B. Cai, J.L. Fife, M.A. Azeem, K.M. Kareh, C. Puncreobutr, D. Tsivoulas, T. Connolley & R.C. Atwood, 2015, NATURE COMMUNICATIONS | DOI: 10.1038/ncomms9300