Skip to main content
padlock icon - secure page this page is secure

Phase Constitution and Mechanical Properties of Carbides in the Ta–C System

Buy Article:

$52.00 + tax (Refund Policy)

Carbides in the Ta–C system were prepared by hot-pressing mixed powders of TaC and Ta in C/Ta atomic ratios of 1.0, 0.9, 0.8, 0.7, and 0.6 at 1800°C for 2 h. The compositions, 1.0, 0.9, and 0.8, produced single face-centered-cubic (fcc) TaCy phase with C/Ta ratios essentially the same as the starting compositions and densities exceeding 96.5% of theoretical. Grain size decreased with increasing carbon deficiency with a corresponding increase in Vickers hardness from 13.5 to 20 GPa. The flexural strength, however, decreased from 650 to 500 MPa due to a decrease in fracture toughness from 5.3 to 3.8 MPa√m. The compositions 0.7 and 0.6 produced two carbide phases, fcc TaCy and rhombohedral -Ta4C3−x phase in the 0.7 composition and -Ta4C3−x and hexagonal-close-packed (hcp) α-Ta2C phase in the 0.6 composition. Fracture toughness measured by single-edge-precracked-beam technique was exceptionally high (12.7±0.7 MPa√m) for the 0.6 composition with a high weight percent of the -Ta4C3−x phase (∼83 wt%). The fracture surface was highly faceted with multiple cleavage crack planes and steps.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Document Type: Research Article

Affiliations: Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112-0560

Publication date: October 1, 2009

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more