Summary
Through activated and liquid-phase techniques, lower sintering temperatures or enhanced densification are possible. Metal powders treated with selected chemical additions can experience enhanced sintering through increased transport rates. It is believed the additives which are present as surface layers provide a short-circuit diffusion path for the host material. Criteria have been formulated for selecting second-phase elements and are reviewed in detail. A disadvantage of the accelerated densification rate is a significant loss in ductility in many systems. Current research efforts are seeking to identify second-phase sintering aids (liquid and solid) which are non-embrittling.
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Zovas, P.E., German, R.M., Hwang, K.S. et al. Activated and Liquid-Phase Sintering—Progress and Problems. JOM 35, 28–33 (1983). https://doi.org/10.1007/BF03338181
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DOI: https://doi.org/10.1007/BF03338181