RU2313591C2 - Method for producing zirconium-niobium master alloy - Google Patents

Abstract

FIELD: metallurgy, namely processes for producing master alloys, possibly production of zirconium alloys used in nuclear power engineering and chemical machine engineering.

SUBSTANCE: according to method main component such as zirconium- containing material is placed onto bottom of crystallizer of electron-beam installation and alloy component is charged onto it such as niobium. At first niobium is melted due to action of electron beam and then zirconium containing material is melted in combination with electromagnetic agitation of melts.

EFFECT: possibility for producing master alloy of uniform chemical content without significant expenses.

7 cl, 1 tbl, 1 dwg

Description

The invention relates to the field of metallurgy, and in particular to methods for producing ligatures, and can be used to obtain zirconium alloys used in nuclear energy and chemical engineering.

A known method of producing ligatures by direct fusion of metals, in which the main component of the ligature is melted in a special unit and overheated. Then alloying components are introduced into the melt in solid or liquid state. The temperature of the alloy is brought to the required level, metallurgical processing is carried out, and then the melt is poured into ingots or plates (Andreev A.L., Anoshkin N.F., Dobatkin V.I. et al. Titanium alloys. Melting and casting of titanium alloys. - M .: Metallurgy, 1978.- p. 95-96).

The disadvantage of this method is that in the case of obtaining a zirconium-niobium ligature, when compact pieces of niobium having a melting point of 2420 ° C are fed into the zirconium melt, the melting point of which is 1852 ° C, niobium is not completely dissolved and there is always a danger of ingress into the ingot ligatures of pieces of unmelted niobium, which subsequently give local inclusions or regions of chemical heterogeneity in zirconium alloy ingots. In the case of feeding niobium in a liquid state into a zirconium melt, the use of a special melting unit for melting niobium and a melt supply system in vacuum is required due to the high chemical activity of niobium.

The problem to which the invention is directed, is to obtain a homogeneous chemical composition of the ligature of zirconium-niobium without significant costs.

The technical result is achieved by the fact that in the proposed method for producing a ligature, including fusing the ligature components, the main component is a zirconium-containing material placed on the bottom of the crystallizer of an electron beam installation, an alloying component, niobium, is loaded on top of it, the niobium is melted under the influence of an electron beam, and then niobium is melted melting of zirconium-containing material in combination with electromagnetic mixing of the melts.

In a particular embodiment of the method, pure niobium is used as an alloying component, which is loaded on top of the zirconium-containing material and melted by the action of an electron beam.

In a particular embodiment of the method, niobium is used as an alloying component after a single electron-beam remelting, which is melted and then further refined using electromagnetic stirring.

In a particular embodiment of the method, niobium is used as an alloying component after reduction smelting, which is melted and then refined using electromagnetic stirring.

In a particular embodiment of the method, zirconium production turns are used as a zirconium-containing material.

In a particular embodiment of the method, pieces of zirconium iodide are used as zirconium-containing material.

In a particular embodiment of the method, a zirconium magnetic sponge is used as a zirconium-containing material.

The drawing shows a photograph of the macrostructure of an ingot of ligature of zirconium - 6.5% niobium.

An example of the implementation of the proposed method is to obtain an ingot of ligature of zirconium - 6.5% niobium in the electron beam skull system VDL-4M, equipped with an electromagnetic stirring system. Zirconium-containing material was laid at the bottom of the mold in the form of production turns of a binary alloy of zirconium - 1.0% niobium weighing 75 kg. A niobium template cut off from an ingot of double electron beam remelting weighing 4.45 kg was laid on top. The furnace was evacuated, checked, and leakage was calculated, which did not exceed 25 L × mm Hg / s.

Under the action of an electron beam, the niobium template was melted, then the zirconium revolutions were melted, the electromagnetic stirring system was switched on, the melt composition was averaged and the melt was drained into a copper form. As a result, an ingot was obtained that was uniform in structure with no pieces of insoluble niobium (see photo) and chemical composition.

Samples were taken from the gate, middle, and bottom parts of the obtained ingot to determine the niobium content. To obtain comparative data, a ligature ingot of the same composition obtained by the closest method was similarly studied. The research results are shown in table 1.

Comparison of the chemical composition of the ingots according to the proposed and closest methods indicates the solution of the problem.

The obtained ingots of the ligature alloy were converted into shavings, which was used to melt the ingots of zirconium alloy of zirconium - 1% niobium, which fully meet the requirements of regulatory documentation.

Table 1 The method of obtaining the ligature Part of the ingot for the study of the composition The content of niobium,% Proposed Litnikovaya 6.78 Average 6.43 Donna 6.54 By the closest analogue Litnikovaya 4.72 Average 6.34 Donna 7.26

Claims (7)

1. A method of producing a zirconium-niobium alloy ligature, comprising fusing the ligature components, characterized in that the main component, a zirconium-containing material, is laid on the bottom of the crystallizer of an electron beam installation, the alloying component, niobium, is loaded onto it, first niobium is melted by the action of an electron beam, and then carry out the melting of zirconium-containing material in combination with electromagnetic mixing of the melts. 2. The method according to claim 1, characterized in that pure diobium is used as an alloying component, which is loaded onto zirconium and melted by the action of an electron beam. 3. The method according to claim 1, characterized in that as the alloying component, niobium is used after a single electron beam remelting, which is melted and then refined using electromagnetic stirring. 4. The method according to claim 1, characterized in that as the alloying component, niobium is used after reduction melting, which is melted and then refined using electromagnetic stirring. 5. The method according to any one of claims 1 to 3, characterized in that the production speed of zirconium is used as a zirconium-containing material. 6. The method according to any one of claims 1 to 3, characterized in that pieces of zirconium iodide are used as the zirconium-containing material. 7. The method according to any one of claims 1 to 3, characterized in that the zirconium magnetic sponge is used as the zirconium-containing material.

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