Study Of Zr08Mo Alloy Process By Vacuum Consumable Arc Melting

Now nuclear power is the core component of green energy.Zirconium alloy is widely used as reactor materials for its excellent nuclear properties.Molybdenum is very beneficial to the corrosion resistance and mechanical properties with nuclear-grade zirconium alloy.Therefore,Mo zirconium alloy is an important research direction of new zirconium alloy.However,because of high melting point and high specific gravity of molybdenum,it is still a difficult problem to obtain Zr Mo alloy with uniform composition and uniform industrial structure.In this paper,a new type of Zr08 Mo nuclear zirconium alloy at the industrial level has been successfully developed through the preparation of intermediate master alloy,reverse segregation alloy cloth,reasonable vacuum consumable melting and heating shrinkage processes.The preparation process of zr-mo parent alloy was studied,the influence of molybdenum ratio on alloying effect and distribution uniformity was analyzed,the influence of melting power and cooling time on the quality of parent alloy was explored,and the existence form and distribution rule of molybdenumin parent alloy were revealed.At the same time,the influence of reverse segregation and smelting process on the uniformity of Molybdenumin Zr08 Mo alloy was studied;the influence mechanism of melting power,electromagnetic stirring intensity and solidification speed on the distribution of molybdenumwas discussed,and the formation and growth rules of solidified structure were analyzed.In addition,the feeding process system of Zr08 Mo alloy at the end of melting was studied,and the effects of two feeding methods and different feeding time on the depth of riser were explored.Finally,the optimum casting process and processing properties of Zr08 Mo alloy were verified.The results show that zr-mo parent alloy with no inclusion,uniform composition and low oxygen content,namely,Zr15 Mo parent alloy,can be prepared by vacuum non-consumable furnace with 12 k W melting power and 20 min cooling time when Mo weight ratio is 15%.The uniformity of molybdenumin Zr08 Mo can be improved by using reverse segregation process,and the better compensation is 10%.Electromagnetic stirring is the dominant factor affecting the distribution uniformity of molybdenumin vacuum consumptive smelting,and with the increase of electromagnetic stirring intensity,the uniformity of molybdenum becomes better,and the better magnetic field stirring current is 6A.The influence of cooling intensity on the uniformity of molybdenum was the second.With the increase of cooling intensity,the uniformity of molybdenumfirst became better and then gradually became worse.The optimized parameter was 40t/h.The effect of melting power on the uniformity of molybdenumis similar to the cooling intensity,and the optimized parameter is 320 kw.At the end of smelting,different heating shrinkage modes have different effects on the appearance of molten pool and the depth of riser.Under the same feeding mode,the riser decreases with the increase of feeding time,and the reasonable feeding time combined with production efficiency is 80 mins.Through the delta 3 mm plate production validation can be concluded that:Zr08Mo alloy processing performance is good,has the very good plasticity technology,it mainly slab quenching organization to top group,corresponding to different quenching microstructure uniformity of ingot casting position,horizontal and vertical at room temperature,high temperature mechanical properties,grain size grade and corrosion resistance can satisfy the requirements of the current commercial zirconium alloy standard,including furuncle corrosion resistance is superior to the modified Zr-4alloy,and good performance.