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High entropy alloy has been proposed in 1995, has been widespread concern at home and abroad, and has now formed a new alloy metal areas around the world. Component of this alloy design concept break through the traditional design pattern of the alloy mainly an alloying element, but also through the optimal design of alloy composition, the high-entropy alloys have high hardness, high strength, high temperature oxidation, high temperature creep change and resistance to corrosion, excellent performance, and has a lot of potential applications. High-entropy alloy cast TiZrHfNbMo object of study, the new alloy by adding C, B element, namely the (TiZrHfNbMo) 100-x Cx and (TiZrHfNbMo) 100-x Bx alloys (x 1.96,3.85,7.41,10.41 16.67), to improve the performance of the high-entropy alloys in TiZrHfNbMo also high entropy alloy cast TiZrHfNbMo heat treatment and high temperature forged by OM, SEM, EDS, XRD and other methods of the alloy system of the organizational structure analysis, and the hardness of this alloy system, the compression performance was tested. The study showed that: the growth of each alloy dendritic mode, the cast TiZrHfNbMo high-entropy alloys only simple BCC solid solution. Add C, B elements, each alloy in addition to forming simple BCC solid solution in vitro (TiZrHfNbMo) 100-xCx alloy precipitated the The intermetallic compound HfC (TiZrHfNbMo) 100-x B x alloy complex compound precipitates. In solid solution strengthening and the precipitation hardening under the joint action with the C, B content increases, the hardness of the alloy increases (TiZrHfNbMo) 16.67 alloys 83.33 C and ( TiZrHfNbMo) 83.33 B 16.67 alloy highest hardness 739HV and 645HV. Addition of C, B elements, the compressive strength of the alloy, the yield strength, the amount of plastic deformation has improved to varying degrees, (TiZrHfNbMo) 92.59 C 7.41 alloy compression best performance, compressive strength of 2061MPa, yield strength of 1421MPa plastic deformation amounted to 19.34%, (TiZrHfNbMo) 83.33 B 16.67 alloy compressive strength up to 2310MPa However, the alloy is almost no plastic deformation capability. The compression process, the alloy understand the cleavage fracture occurs. TiZrHfNbMo high entropy alloys after heat treatment at 1500 ℃, still body-centered cubic structure of the solid solution phase composition, tissue morphology changes and refinement, a more uniform distribution of each element. After heat treatment of the alloy hardness of 512HV, a 19.6% increase compared with cast alloy hardness. TiZrHfNbMo high entropy alloy after high temperature forging and heat treatment, the organization still the body-centered cubic structure of the solid solution phase composition. TiZrHfNbMo high entropy alloy heat processing, forged by the high temperature of 1000 ℃, the organization is divided into three regions due to different degrees of deformation. Upper and lower end cast dendrite middle rheological organization, both sides of the thick dendrites.
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