Preparation of Ta/W Composite by CVD

Abstract

The Ta/W composites with 10%W, 13%W and 18%W were prepared by chemical vapor deposition (CVD). The properties of Ta/W composites were investigated by optical microscopy (OM), scanning electron microscopy (SEM ) and tensile test. The results show that it is possible to prepare Ta/W composites with different W volume fractions by CVD, and the actual densities of the composites are more than 99.4% of the theoretical density. Both Ta and W layers have columnar grain structures, and the more close to the interface, the more fine the grains are. The mechanical properties of CVD Ta/W are better than those of CVD Ta or CVD W. After hot treatment(1600 ℃×2 h),the diffused layers of the composites have become more wider and the mechanical properties are increased remarkably, and the tensile strength of the CVD Ta/W composite with 18%W is 660 MPa.

Keywords

• chemical vapor deposition (CVD)
• Ta/W composite
• volume fraction of W
• mechanical properties