Study On Relationship Between Microstructure And Properties Of High Zirconium Niobium Alloy

Nb-Zr alloys maintained the low temperature plasticity of niobium, and had high mechanical properties. Zirconium added to niobium improved the strength of the alloy without affecting the plasticity and working properties of the alloy, and improved high-temperature strength and oxidation resistance of niobium. Zirconium could also improve resistance to oxidation and corrosion of alkali metal alloys. NbZr10 is a new functional niobium alloy material. After being arc melted, adding the active metal element Zr could be solid solution strengthened, and adding elements C could be aging strengthened. Appropriate processing and heat treatment to control the morphology and distribution of carbide precipitates, to improve the strength NbZr10 alloy, and can greatly improve high-temperature creep resistance of the alloy.The alloy had been twice electric arc smelted, to avoid the problems of vacuum electron beam melting, such as melting loss zirconium atoms serious, overheating, distribution in the niobium of zirconium alloy element did not uniform. The impurities in Nb and Zr plate were controlled The ingot was homogenized at 1300 ℃ for 24 h, Undissolved Zr-rich phase distributed at dendrite and grain interior dissolved significantly, the organization boundaries became clear.Used of hot-rolled to investigate the high temperature mechanic properties of NbZr10 alloy. The temperature was 1323 K, and the reduction of per pass was 10%, 15% and 20%. The roll diameter was Φ550mm, and the roll line speed was 30 mm / min. The billets deformed uniformly, and alloy structure was significantly streamlined. According to the hot rolling test parameters, thermal simulation test temperature chose 1273 K, 1123 K and 1373 K, strain rate chose 0.01 s-1,0.1 s-1, and 1 s-1respectively. Gleeble-1500 thermal simulation testing was used to test the machine isothermal constant strain rate compression tests, to research the high temperature deformation behavior. To control the hot forming process of Nb10 Zr alloy reasonably and improve its mechanical properties. Developed a reasonable reference and provided a theoretical basis for industrial rolling. According to true stress-strain curves of NbZr10 alloys in thermal compressive thermal simulation experiments, the stress-strain constitutive equation of NbZr10 alloy mechanical properties at high temperature deformation was established.