Effect of High-Temperature Deformation on the Physical and Mechanical Properties of In Situ Titanium Composites with Silicide-Boride Reinforcement

The efficiency of thermomechanical processing was studied to optimize the mechanical properties of cast ternary and multicomponent hypoeutectic titanium-based alloys with silicide-boride reinforcement, produced by electron-beam crucible-skull melting. All the alloys studied exhibit low plasticity in cast state. High-temperature deformation, such as forging of samples heated to 1050 degrees C in air, can significantly enhance the properties of the alloys: the plasticity of ternary Ti-Si-B alloys increases by four to six times (from 0.5 to 2-3%) and their fracture toughness increases by three times (from 11 to 36 MPa center dot m(0.5)). The plasticity of the alloys with Zr, Al, and Sn additions increases by one order of magnitude (to 0.2-0.3%) and their fracture toughness by almost twice. The greatest high-temperature creep-rupture resistance at a fracture toughness of 26 MPa center dot m(0.5) is shown by the Ti(80Z)r(1.2)Al(5.5)Sn(2.1)Si(8.7)B(2.5) alloy: 1038, 887, and 572 MPa at 600, 700, and 800 degrees C, respectively.