Journal of Materials Science

, Volume 7, Issue 12, pp 1434–1442 | Cite as

Microstructural development during the liquid-phase sintering of VC-Co alloys

  • R. Warren
Papers

Abstract

A study was made of the microstructural changes that occur during the liquid-phase sintering of VC-Co alloys. It was found that considerable growth of the carbide grains takes place and that this growth can be described by the equation:
$$\bar d^3 - \bar d_o^3 = Kt$$

The value of the rate constant,K, At 1450°C was found to be in good agreement with that predicted by a modified Wagner analysis for a solution/precipitation process controlled by diffusion through the liquid. The observed variations in the growth rate both with temperature, between 1380 and 1500°C, and with the volume fraction of the liquid phase are also consistent with this theory.

The contiguity of the carbide grains at the start of sintering is relatively high and is affected by the pre-sintering history of the specimen. During the early stages of sintering, however, the contiguity falls rapidly to a low value which subsequently remains relatively constant. Observations were made which suggest that the carbide does not form a continuous skeleton during sintering.

Keywords

Polymer Growth Rate Carbide Liquid Phase Microstructural Development 

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Copyright information

© Chapman and Hall Ltd 1972

Authors and Affiliations

  • R. Warren
    • 1
  1. 1.Department of Metallurgy and Materials TechnologyUniversity of SurreyGuildfordUK

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