Method for preparing beryllium-titanium alloy rod through suspension smelting

Abstract

The invention provides a method for preparing a beryllium-titanium alloy rod through suspension smelting. The method comprises the following steps that raw material titanium and raw material beryllium blocks are put into a crucible according to the proportion of 30-90 wt% of beryllium and 10-70 wt% of titanium; the smelting chamber is vacuumized, heating is started when the vacuum degree reaches 100 Pa or below, the heating power is increased at the speed of 10 KW / 10 min, and materials in the crucible are melted; when the materials are heated to a preset temperature range of 700-1000 DEG C, the roots pump, the diffusion pump and the mechanical pump are sequentially closed; when the material is heated to a preset temperature of 1000 DEG C, argon with preset purity is filled for protection; the heating power is increased by a preset value, so that the temperature of the melt is increased to 1400-1450 DEG C, refining melting down is kept for 5-10 minutes, and the melt is fully stirred; cooling and controlling the temperature of the melt to be 1200-1350 DEG C, and casting the melt into a metal ingot mold; and processing the cast ingot obtained by pouring into an electrode bar.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation of beryllium-titanium alloy bars, and particularly relates to a method for preparing beryllium-titanium alloy bars by levitation melting. Background Art

[0002] Beryllium-titanium alloy has the advantages of light weight, high strength, corrosion resistance, excellent high-temperature strength and mechanical properties. Beryllium-titanium alloy, as a substitute for metallic beryllium as a neutron multiplier in nuclear reactors, has obvious advantages. The rapid solidification of beryllium-titanium alloy promotes the formation of Be 12 Ti phase. Beryllium Be 12 Ti has a very high neutron multiplication ability due to the fact that the atomic proportion of Be in its intermediate compound is as high as 93%, good high-temperature oxidation resistance, and high high-temperature fracture strength. Be 12 Ti can effectively improve the tritium breeding rate and release rate, and has a relatively small reaction with water vapor, and fewer defects are formed due to the residue of deuterium under irradiation conditions. At the same time, with the decrease of beryllium content, the raw material cost of beryllium-titanium alloy is lower than that of beryllium, which can save precious beryllium resources. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing beryllium-titanium alloy bars by levitation melting, which includes the following steps:

[0004] Step 1, material preparation: Loading raw materials titanium and raw beryllium blocks into a crucible according to the ratio of beryllium 30-90 wt.%, titanium 10-70 wt.%.

[0005] Step 2, melting: Evacuating the melting chamber, starting heating when the vacuum degree reaches below 100 Pa, and increasing the heating power at a speed of 10 KW / 10 min to melt the materials in the crucible.

[0006] Step 3, argon filling: When the materials in the crucible are heated to a predetermined temperature range of 700-1000 °C, turn off the Roots pump, diffusion pump and mechanical pump in sequence; when the materials in the crucible are heated to a predetermined temperature of 1000 °C, fill with argon gas of a predetermined purity for protection.

[0007] Step 4, refining: Increasing the heating power by a predetermined value to raise the melt temperature to 1400 °C - 1450 °C, maintaining refining and melting for 5-10 minutes, and fully stirring the melt.

[0008] Step 5, casting: Cooling down and controlling the melt temperature between 1200-1350 °C, and casting the melt into a metal ingot mold.

[0009] Step 6, machining: Machining the cast ingot obtained by casting into an electrode bar.

[0010] Further, in step 1, the raw material titanium is sponge titanium with a purity higher than 99.0%, and the purity of the raw material beryllium block is higher than 99.0%.

[0011] Further, in step 2, the melting vacuum is maintained at 10 - 100 Pa.

[0012] Further, in step 3, the pressure of the inert gas introduced is 0.2 - 0.5 MPa.

[0013] Further, the inert gas is argon with a purity higher than 99.99%.

[0014] Further, in step 4, the increased predetermined power is 60 - 100 KW.

[0015] Further, in step 5, the metal ingot mold is lowered and drawn into a rod.

[0016] Further, it further includes step 7, and the electrode rod is used to prepare beryllium-titanium spheres by plasma rotating electrode method.

[0017] The beryllium-titanium alloy rod prepared by the present invention is used for the production of beryllium-titanium spheres and beryllium-titanium powder. In this production process, the utilization rate of the beryllium-titanium rod is high, and the prepared beryllium-titanium spheres and powder have a wide particle size range, high sphericity, good fluidity, and few satellite balls and hollow balls. Specific Embodiments

[0018] The present invention aims at preparing a beryllium-titanium alloy rod by suspension melting. The suspension melting process is adopted, and it is cast into a metal mold, and the ingot is machined for plasma rotating electrode atomization to prepare powder. The scheme of the present invention will be described in detail through two embodiments below.

[0019] Example 1

[0020] 1. Load sponge titanium (purity higher than 99.0%) and beryllium block (purity higher than 99.0%) into a water-cooled copper crucible, and the composition is designed as 90 wt.% beryllium and 10 wt.% titanium.

[0021] 2. Evacuate the melting chamber. When the vacuum reaches below 100 Pa, start heating, increase the heating power at a rate of 10 KW / 10 min to melt the materials in the crucible, and fill with argon for protection when the temperature of the materials in the crucible reaches the predetermined temperature.

[0022] In this step, the melting vacuum is maintained at 10 - 100 Pa; when the temperature of the melt reaches the predetermined range of 700 - 800 °C, turn off the Roots pump, diffusion pump and mechanical pump in sequence to reduce material volatilization; when the materials in the crucible are heated to 1000 °C, inert gas should be immediately filled for protection; the pressure of the inert gas introduced is 0.2 - 0.5 MPa, and the purity of the inert gas argon is higher than 99.99%.

[0023] 3. Continue to increase the heating power to 80 KW, so that the temperature of the molten liquid reaches 1400°C - 1450°C, maintain refining and melting for 5 minutes, and fully stir the molten liquid.

[0024] 4. Then cool down and control the temperature of the molten liquid between 1200 - 1350°C, and pour the molten liquid into the metal ingot mold.

[0025] 5. Process the prepared ingot into an electrode rod, which is used for making beryllium-titanium small balls by plasma rotating electrode method and can be used as a neutron multiplication material for nuclear reactors.

[0026] In this step, the base of the metal ingot mold is lowered, drawn into a rod, and a temperature gradient is formed. The prepared rod is used for the plasma rotating electrode atomization powder making process to prepare beryllium-titanium small balls.

[0027] Example 2

[0028] 1. Load sponge titanium (purity higher than 99.0%) and beryllium blocks (purity higher than 99.0%) into a water-cooled copper crucible. The composition is designed as 30 wt.% beryllium and 70 wt.% titanium.

[0029] 2. Evacuate the melting chamber. When the vacuum degree reaches below 100 Pa, turn on the heating, increase the heating power at a speed of 10 KW / 10 min to melt the materials in the crucible, and fill with argon for protection when the temperature of the materials in the crucible reaches the predetermined temperature.

[0030] In this step, the melting vacuum degree is maintained at 10 - 100 Pa; when the temperature of the melt reaches the predetermined range of 800 - 1000°C, turn off the Roots pump, diffusion pump, and mechanical pump in sequence to reduce material volatilization; when the heating temperature of the materials in the crucible reaches 1000°C, inert gas should be immediately filled for protection; the pressure of the introduced inert gas is 0.2 - 0.5 MPa, and the purity of the inert gas argon is higher than 99.99%.

[0031] 3. Continue to increase the heating power to 60 KW, continue to raise the temperature of the molten liquid to 1400°C - 1450°C, maintain refining and melting for 10 minutes, and fully stir the molten liquid.

[0032] 4. Then cool down and control the temperature of the molten liquid between 1250 - 1350°C, and pour it into the metal ingot mold.

[0033] 5. Process the prepared ingot into an electrode rod, which is used for making beryllium-titanium small balls by plasma rotating electrode method and can be used as a neutron multiplication material for nuclear reactors.

[0034] In this step, the base of the metal ingot mold is lowered, drawn into a rod, and a temperature gradient is formed. The prepared rod is used for the plasma rotating electrode atomization powder making process to prepare beryllium-titanium small balls.

[0035] Example 3

[0036] 1. Load titanium sponge (purity higher than 99.0%) and beryllium blocks (purity higher than 99.0%) into a water-cooled copper crucible. The composition is designed as 30 wt.% beryllium and 70 wt.% titanium.

[0037] 2. Evacuate the melting chamber. When the vacuum degree reaches below 100 Pa, start heating and increase the heating power at a rate of 10 KW / 10 min to melt the materials in the crucible. When the temperature of the materials in the crucible reaches the predetermined temperature, fill with argon for protection.

[0038] In this step, the melting vacuum degree is maintained at 10 - 100 Pa; when the temperature of the melt reaches the predetermined range of 900 - 1000 °C, turn off the Roots pump, diffusion pump, and mechanical pump in sequence to reduce material volatilization; when the heating temperature of the materials in the crucible reaches 1000 °C, immediately fill with inert gas for protection; the pressure of the inert gas introduced is 0.2 - 0.5 MPa, and the purity of the inert gas argon is higher than 99.99%.

[0039] 3. Continue to increase the heating power by 100 KW and continue to raise the temperature of the melt to 1400 °C - 1450 °C, and keep refining and melting for 10 minutes with the melt fully stirred.

[0040] 4. Then cool down and control the temperature of the melt between 1250 - 1350 °C, and pour it into a metal ingot mold.

[0041] 5. Process the prepared ingot into an electrode rod for use in the production of beryllium-titanium small balls by plasma rotating electrode method, which can be used as neutron multiplication materials in nuclear reactors.

[0042] In this step, the base of the metal ingot mold is lowered and drawn into a rod, forming a temperature gradient. The prepared rod is used in the plasma rotating electrode atomization powder-making process to prepare beryllium-titanium small balls.

[0043] Please note that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity in description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope described in this specification. The above embodiments only represent several implementation manners of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of this application, several deformations and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of the patent of this application should be subject to the appended claims.

Claims

1. A method for preparing beryllium-titanium alloy rods by suspension smelting, characterized in that: The method comprises the following steps: Step 1, preparing materials: putting raw titanium and raw beryllium blocks into a crucible according to a ratio of 30-90wt.% beryllium and 10-70wt.% titanium; Step 2, melting: evacuate the melting chamber, turn on the heating when the vacuum degree reaches below 100 Pa, increase the heating power at a rate of 10 kW / 10 min, and melt the material in the crucible; Step 3, filling with argon: when the material in the crucible is heated to a predetermined temperature range of 700-1000°C, the Roots pump, the diffusion pump and the mechanical pump are turned off in sequence; when the material in the crucible is heated to a predetermined temperature of 1000°C, argon gas of a predetermined purity is filled in for protection; Step 4, refining: increase the heating power by a predetermined value so that the melt temperature rises to 1400°C-1450°C, keep refining and melting for 5-10 minutes, and stir the melt thoroughly; Step 5, casting: cooling and controlling the melt temperature between 1200-1350°C, and casting the melt into a metal ingot mold; Step 6, machining: machining the cast ingot into an electrode rod.

2. The method according to claim 1, characterized in that In step 1, the raw material titanium is sponge titanium with a purity higher than 99.0%, and the raw material beryllium block has a purity higher than 99.0%.

3. The method according to claim 1, characterized in that In step 2, the vacuum degree of the melt is maintained at 10-100Pa.

4. The method according to claim 1, characterized in that In step 3, the pressure of the inert gas introduced is 0.2-0.5 MPa.

5. The method according to claim 4, characterized in that The inert gas is argon, and the purity of argon is higher than 99.99%.

6. The method according to claim 1, characterized in that In step 4, the increased predetermined power is 60-100KW.

7. The method according to claim 1, characterized in that In step 5, the metal ingot mold is lowered and drawn into a rod.

8. The method according to claim 1 or 7, characterized in that The method also includes step 7, wherein the electrode rod is used to prepare beryllium titanium pellets by using a plasma rotating electrode.