Wetting of nonmetallic materials by metal melts in the conditions simulating conditions of space vacuum and an atmosphere of the Moon


I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Krzhizhanovsky str., 3, Kyiv, 03142, Ukraine
Adhesion of Melts and Brazing of Materials - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2014, #47


Wetting of ionic compounds (oxides and fluorides) and graphite by Al, In—Ti and Cu—Ti in an interval of temperatures 700––1200 °С in vacuum 1×10-2–– 5×10-4 Pa by a sessile drop method with use of additional investigation methods was studied. The contact angles at wetting of substrates by aluminum at a different degree of vacuum are approximately equal. Contact angles decrease at introduction in In already 5% (at.) Ti for MgF2, SrF2, CaF2, SiO2, Al2O3 and graphite accordingly up to 8, 10, 10, 20, 25, 42 degree. On the basis of results on wetting, it is possible to assert that the vacuum is lower 10-3 Pa is sufficient for researches of capillary characteristics of metal melts. The additional methods of researches (capillary purification of alloy), and also drawing of metal coverings on researched solid surfaces which interact with liquid metal with exothermic effect, allow to simulate conditions of space vacuum. Influence of vacuum was revealed at wetting of oxides by Cu—Ti alloys at 1200 °С. In vacuum 1×10-2 Pa the threshold of wetting was observed—the angle practically did not change at increase in concentration up to 8—10% (at.) titanium.