Mechanical properties and fracture characteristics of molybdenum-tungsten alloys at high temperature
Molybdenum-based and tungsten-based alloys have been used as structural materials in many technical fields. It was previously determined that the critical multilateralization stage has a great influence on the formation of mechanical properties of powder metallurgy tungsten. It is important to study the effect of this process on the properties of other materials, whether they are made by powder metallurgy or vacuum arc smelting.
The temperature dependence of mechanical properties and fracture characteristics of Mo-30W and Mo-30W-NBC-C molybdenum-tungsten alloys prepared by standard powder metallurgy method was taken as the research object. For Mo-30W alloy, LIM-10 alloy and B-MIT tungsten, they were selected from hot rolled sheet with thickness of 1-2 mm. For the Mo-30W-NbC-C alloy, it was selected from 52 and 65 mm diameter bars in the deformed state (e=75%) and from 64X23 mm diameter tubing in the deformed state (e=75%) and recrystallization state (annealed at 1700 degrees Celsius for 2 hours). According to the test results, the marked hardness value is not lower than the value measured on the IIMT-3 instrument at 20 degrees Celsius, They are respectively 3300 Mpa (deformed Mo-30% W alloy sheet), 3400 Mpa (deformed Mo-30% W-NBC-C alloy bar) and 2610 Mpa (deformed Mo-30% W-NBC) C alloy pipe) and 2770 Mpa (Mo-30%W-NbC-C alloy pipe in recrystallization state). It should be noted that the deformation state. The microhardness of the pipe is much lower. Obviously, non-thermal weakening occurs during extrusion due to autogenic recombination and dislocation annihilation.
