INTERACTION OF STRUCTURAL COMPONENTS OF A NICKEL COMPOSITE IN VACUUM AT 1150 °С

Abstract

The interaction of a Ті + 10Мо titanium alloy, which serves as a matrix in a tribological material, with calcium fluoride СaF₂ and boron nitride ВN, which play the role of a solid lubricant, during their heating and sintering in a vacuum of 10^–5 Pa at 1150 °С for 15 and 120 min, respectively, has been studied. In the heating of a Ті + 10 Мо–CaF₂ model specimen for 15 min and sintering of Ті + 10 Мо + CaF₂ CAM1 for 120 min, calcium fluoride does not interact with the Ті + 10Мо matrix of the material and does not change its composition and structure; a transition layer between the matrix and solid lubricant does not form. Thus, calcium fluoride preserves its initial lubricating properties. In the sintering of Ті + 10 Мо + CaF₂ CAM1 for 120 min, a composite antifriction material with a microheterogeneous structure is synthesized. Its structure is a mixture of solid solutions of molybdenum in α- and β-titanium, which has a body-centered cubic lattice and face-centered hexagonal lattice, in which calcium fluoride CaF₂ is distributed in the form of inclusions. In the heating of a Ті + 10 Мо + ВN model specimen for 15 min and sintering of Ті + 10 Мо + ВN CAM2 for 120 min, the interaction of the Ті+10Мо alloy with boron nitride BN occurs to form a transition layer with the phase composition α-TiMo + TiB + TiN + ВN. In the sintering of Ті + 10 Мо + ВN CAM2 for 120 min, a composite material with a microheterogeneous structure is synthesized. Its structure is a solid solution of Mo in α-Ті with a face-centered hexagonal lattice, strengthened by products of interaction of titanium with nitrogen and boron, TiN and ТіВ, in which boron nitride BN is distributed in the form of inclusions.