Preparation method of zirconium alloy ingot

Abstract

The invention discloses a preparation method of a zirconium alloy ingot. The preparation method comprises the following steps of 1, mixing zirconium sponge with an alloy raw material, and pressing toobtain an electrode block; 2, welding the electrode block in a protective atmosphere to obtain a consumable electrode; 3, carrying out vacuum consumable smelting on the consumable electrode in a current control mode to obtain a primary cast ingot; and 4, carrying out vacuum consumable melting on the primary cast ingot by adopting an electrode smelting speed control mode to obtain the zirconium alloy cast ingot. According to the method, vacuum consumable smelting is carried out in the current control mode, the problems that a consumable electrode block is uneven in density distribution and relatively poor in stability in the smelting process are solved, then vacuum consumable smelting is carried out in the electrode smelting speed control mode, a reasonable electrode smelting speed and a reasonable molten pool depth are established, the optimal purity and alloy component uniformity of the zirconium alloy ingot are guaranteed, and the problem that the quality fluctuation of the zirconiumalloy ingot smelted by an existing vacuum consumable electro-arc furnace is large is solved.

Description

technical field [0001] The invention belongs to the technical field of metal material preparation, and in particular relates to a method for preparing a zirconium alloy ingot. Background technique [0002] Zirconium and its alloys have the characteristics of small neutron absorption cross section and good compatibility with uranium, and are one of the most widely used metal materials in nuclear reactor fuel cladding and structural materials. As zirconium is an active metal, conventional smelting methods will inevitably cause pollution of oxygen, nitrogen or crucible materials. Nuclear-grade zirconium alloys with strict control of impurity elements are currently smelted and ingot-cast by vacuum consumable arc melting. Vacuum consumable arc melting uses arc discharge formed by low voltage and high current as a heat source to melt metal and produce ingots. The quality of zirconium alloy ingots is mainly related to surface quality, riser depth, and composition uniformity, which...

AI Technical Summary

Problems solved by technology

In this method, the self-consumable electrode is first smelted in vacuum by controlling the current to obtain an ingot, which solves the problem of uneven density distribution of the consumable electrode and relatively poor stability during the smelting process. The ingot adopts the method of controlling the melting speed of the electrode for vacuum self-consumption smelting, and establishes a reasonable melting speed of the electrode and the depth of the molten pool, so that the gas and impurities in the molten droplet and the molten pool can be effectively removed, further improving the purity of the ingot, and ensuring The zirconium alloy ingot has the best purity and alloy composition uniformity, can accurately control the melting process, and solves the problem of large fluctuations in the quality of the zirconium alloy ingot melted by the existing vacuum consumable electric arc furnace

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