Abstract
Influences of low temperature annealing on the properties of WC-TiC-10%Co alloys having various carbon and titanium carbide contents were studied. Specimens were vacuum-sintered at 1400 and 1430°C for 1 hr, furnace-cooled to room temperature and subsequently vacuumannealed at 800°C for 2.5-150 hr. Some properties of the alloys influenced by the annealing, such as lattice parameters of γ and β phases, saturation magnetization, density, hardness and transverse-rupture strength were determined. The results obtained were as follows: (1) The dissolved W in γ phase in the alloys (free from either η phase or free carbon phase) precipitated in the form of Co3W. The amount of precipitation increased with decreasing carbon content in the alloys. (2) The rate of precipitation was larger than those in WC-Co and WC-TaC-Co alloys. (3) However, transverse-rupture strength of the alloys was not affected by the annealing, differing from the cases in WC-Co and WC-TaC-Co alloys. (4) No changes in density, hardness and saturation magnetization of the alloys were observed.
