Wettability of Cu-Ti Alloys on Graphite in Different Placement States of Copper and Titanium at 1373 K (1100 °C)

The wetting behavior of the Cu-Ti alloys with titanium content of 4, 6, and 10 mass pct on the graphite substrate was investigated at 1373 K (1100 °C), using the sessile drop method in three kinds of placement states, which were from top to bottom settled as pre-alloyed Cu-Ti/C, Ti/Cu/C, and Cu/Ti/C, respectively. The results showed that a TiC layer was formed at the interface between Cu-Ti alloy and graphite substrate in all cases. The wettability improved with increasing titanium content from 4 to 10 mass pct. And with the same Ti content, the best wettability was obtained in the placement state of Cu/Ti/C, followed by Ti/Cu/C and pre-alloyed Cu-Ti/C. The different wetting behaviors of three kinds of placement states can be attributed to the contact area between the generated Cu-Ti liquid phase and the graphite substrate during the heating process, as well as the actual content of molten Ti in the generated Cu-Ti liquid phase.