High-hardness titanium-zirconium alloy material and preparation method thereof

Abstract

The invention relates to a high-hardness titanium-zirconium alloy material and a preparation method thereof.The titanium-zirconium alloy mainly contains titanium and zirconium and further contains, by weight, 1%-2.5% of chromium, 0.5%-2% of molybdenum, 0.5%-2% of vanadium, 1.5%-2% of niobium, 2%-4% of aluminum and trace unavoidable impurities; the preparation method comprises the following steps that 1, raw materials are evenly mixed and pressed into an electrode, first, primary electron beam melting is carried out, and impurities such as H and C in alloy can be well removed through electron beam melting; 2, the surface of the cast ingot subjected to electron beam melting is planed, then forging is conducted, the cast ingot is forged into the vacuum consumable electrode furnace electrode specification, and surface oxide skin is turned; 3, the electrode is sequentially smelted for the third time in a vacuum consumable electric arc furnace, and a third-time smelted cast ingot is obtained; 4, after the surface of the cast ingot is scalped, ultrasonic flaw detection is carried out, a head riser is removed, multi-heating-number upsetting and drawing forging is carried out, and the cast ingot is rolled into the required specification; and 5, the rolled finished product is subjected to solid solution aging heat treatment, and the high-hardness titanium-zirconium alloy is obtained. And the hardness can reach 50-55 HRC (Rockwell hardness).

Description

Technical Field

[0001] The invention belongs to the field of alloy materials and relates to a high-hardness titanium-zirconium alloy material and a preparation method thereof. Background Art

[0002] Titanium-zirconium alloy is an alloy composed of titanium, zirconium, and some trace elements. It has advantages such as high strength and high corrosion resistance. Titanium-zirconium alloy is a material with broad application prospects. It plays an important role in aerospace, automotive manufacturing, electronics, architectural decoration and other fields.

[0003] In some specific fields, the requirements for titanium-zirconium alloys are very high, and titanium-zirconium alloys are required to have higher hardness to increase the service life of some key components. Summary of the Invention

[0004] The primary purpose of the present invention is to provide a high-hardness titanium-zirconium alloy, which has high hardness to meet the requirements of some specific fields and increase the service life of key components.

[0005] To achieve this object, in a basic embodiment, the present invention provides a high-hardness titanium-zirconium alloy, which, in addition to mainly containing titanium and zirconium, also contains 1-2.5% by weight of chromium, 0.5-2% by weight of molybdenum, 0.5-2% by weight of vanadium, 1.5-2% by weight of niobium, 2-4% by weight of aluminum, and trace amounts of unavoidable impurities.

[0006] Cr is a eutectic β-stabilizing element that has a solid solution strengthening effect on the β phase and is the main additive for high-strength and high-hardness titanium alloys. Nb is an isomorphous β-stabilizing element that can improve the oxidation resistance of the alloy. The addition of Mo and V can lower the phase transition point of the alloy and increase the hardenability of the alloy, thereby enhancing the heat treatment strengthening effect. Aluminum can improve the strength and hardness of the alloy through solid solution strengthening.

[0007] Impurity elements such as C, N, H, and O are harmful elements that will reduce the plasticity of the alloy and increase the brittleness of the alloy. The content of impurity elements must be strictly controlled. The present invention uses a single electron beam melting process, which can effectively remove impurities such as H and C from the alloy.

[0008] In a preferred embodiment, the present invention provides a high-hardness titanium-zirconium alloy, wherein the titanium alloy is composed of the following substances in weight percentage: 30-60% titanium, 50-70% zirconium, 1-2.5% chromium, 0.5-2% molybdenum, 0.5-2% vanadium, 1.5-2% niobium, 2-4% aluminum, and the rest are unavoidable impurities.

[0009] The second object of the present invention is to provide a method for preparing the titanium-zirconium alloy as described above, so that the titanium-zirconium alloy has higher hardness.

[0010] To achieve this object, in a basic embodiment, the present invention provides a method for preparing the novel titanium-zirconium alloy as described above, the method comprising the following steps:

[0011] (1) The raw materials are mixed and pressed into electrodes, and electron beam melting is first performed. Electron beam melting can effectively remove impurities such as H and C in the alloy;

[0012] (2) Planing the surface of the ingot after electron beam melting, and then forging it into the specifications of the vacuum consumable furnace electrode, and turning the surface oxide scale;

[0013] (3) melting the electrode three times in a vacuum consumable arc furnace to obtain a three-melting ingot;

[0014] (4) After the surface of the ingot is peeled, it is ultrasonically inspected, the head riser is removed, and multiple-fire forging is performed and rolled into the required specifications;

[0015] (5) The rolled product is subjected to solution aging heat treatment to obtain a high-hardness titanium-zirconium alloy.

[0016] In a preferred embodiment, the present invention provides a method for preparing the titanium-zirconium alloy as described above, wherein the forging temperature is 1100-1200°C.

[0017] In a preferred embodiment, the present invention provides a method for preparing the titanium-zirconium alloy as described above, wherein the rolling temperature is 980-1100°C.

[0018] The beneficial effect of the present invention is that the titanium-zirconium alloy produced by the present invention has higher hardness. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is further described below with reference to the examples.

[0020] Example 1: Preparation of titanium alloy materials of various formulas

[0021] Titanium-zirconium alloy materials with the formulations listed in Table 1 were prepared using the following method (the content of each substance is expressed in weight percentage; the total weight percentage of carbon, hydrogen, oxygen, and nitrogen in the inevitable impurities of each formulation is less than 0.4%).

[0022] The resulting ingot is then surface-skinned and ultrasonically inspected, with the riser removed. The ingot is then subjected to multi-fire drawing forging to produce a 150*150*L billet. The first fire is performed at 1150°C, with a holding time of 240-300 minutes, followed by three draws and three turns, with a deformation of 50%-70%. The second fire is performed at 1020°C, with a holding time of 180-200 minutes, followed by three draws and three turns, with a deformation of 50%-70%. The third fire is performed at 980°C, with three draws and three turns, with a holding time of 120-150 minutes, with a deformation of 50%-70%. The fourth fire is performed at 950°C, with three draws and three turns, with a holding time of 60-100 minutes, with a deformation of 50%-70%.

[0023] The billet is rolled in one pass to produce a 100*L φ mill bar at a rolling temperature of 920°C for 60-100 minutes. The mill bar is then peeled, ground, and then rolled in a second pass at 880°C for 30-60 minutes to obtain the desired bar specifications.

[0024] The bars are subjected to a special heat treatment to produce a high-hardness titanium-zirconium alloy. Heat treatment regime: solution temperature 720°C, holding time 30-120 minutes, water cooling upon exiting the furnace, aging temperature 300-600°C, holding time 4-24 hours.

[0025] Example 2: Preparation of titanium-zirconium alloy materials of various formulations

[0026] Titanium-zirconium alloy materials with the formulations listed in Table 1 were prepared using the following method (the content of each substance is expressed in weight percentage; the total weight percentage of carbon, hydrogen, oxygen, and nitrogen in the inevitable impurities of each formulation is less than 0.4%).

[0027] Alloy materials are prepared according to the composition of each formula, and the alloy materials are mixed evenly and then pressed into electrodes. They are melted once in an electron beam melting furnace to form slabs. The slabs are planed to remove surface oxide scale and forged once at a forging temperature of 1150°C to form round bars with a diameter of 220 mm. The round bars are peeled and used as electrodes for melting in a vacuum consumable furnace. Three vacuum consumable melting processes are carried out to obtain the final ingot.

[0028] The resulting ingots were surface-skinned, ultrasonically inspected, and the head riser removed before undergoing multi-fire drawing forging to produce billets measuring 150 x 150 x L. The first fire involved a forging temperature of 1150°C, a holding time of 300 minutes, three draws, and a deformation of 66%. The second fire involved a forging temperature of 1020°C, a holding time of 200 minutes, three draws, and a deformation of 66%. The third fire involved a forging temperature of 980°C, three draws, and a holding time of 150 minutes, with a deformation of 66%. The fourth fire involved a forging temperature of 950°C, three draws, and a holding time of 100 minutes, with a deformation of 66%.

[0029] The billet was rolled in one pass to produce a 100*L φ mill bar at a rolling temperature of 920°C and a holding time of 100 minutes. The mill bar was then peeled, ground, and then rolled in a second pass at a rolling temperature of 880°C and a holding time of 60 minutes to obtain the desired bar specifications.

[0030] The bars are subjected to a special heat treatment to produce a high-hardness titanium-zirconium alloy. The heat treatment system is: solution temperature 720°C, holding time 120 minutes, water cooling after removal from the furnace, aging temperature 580°C, holding time 24 hours.

[0031] The properties of the titanium-zirconium alloy prepared by the above method are shown in Table 2. The hardness can reach 50-55HRC.

[0032] Table 1 Titanium-zirconium alloy materials with different formulations

[0033]

[0034] Table 2 Comparison of hardness of titanium-zirconium alloy materials with different formulations

[0035] Conventional zirconium alloy Recipe 1 Recipe 2 Hardness (HRC) 28 51.5 52

Claims

1. A high-hardness titanium-zirconium alloy material and a preparation method thereof, characterized in that: The high-hardness titanium-zirconium alloy material mainly contains titanium and zirconium, and also contains 1-2.5% by weight of chromium, 0.5-2% by weight of molybdenum, 0.5-2% by weight of vanadium, 1.5-2% by weight of niobium, 2-4% by weight of aluminum, and trace amounts of inevitable impurities.

2. The high hardness titanium-zirconium alloy material according to claim 1, characterized in that: The high-hardness titanium-zirconium alloy material contains 30-60% by weight of titanium.

3. The high hardness titanium-zirconium alloy material according to claim 1, characterized in that: The high-hardness titanium-zirconium alloy material contains 50-70% zirconium by weight.

4. The high hardness titanium-zirconium alloy material according to claim 1, characterized in that: The total weight percentage of carbon, hydrogen, oxygen and nitrogen in the trace inevitable impurities is less than 0.4%.

5. The high hardness titanium-zirconium alloy material according to claim 1, characterized in that: The high-hardness titanium-zirconium alloy material is composed of the following substances in percentage by weight: 30-60% titanium, 50-70% zirconium, 1-2.5% chromium, 0.5-2% molybdenum, 0.5-2% vanadium, 1.5-2% niobium, 2-4% aluminum, and the rest are trace amounts of inevitable impurities.

6. The method for preparing a high-hardness titanium-zirconium alloy material according to any one of claims 1 to 5, characterized in that: The preparation method comprises the following steps: (1) The raw materials are mixed and pressed into electrodes, and electron beam melting is first performed. Electron beam melting can effectively remove impurities such as H and C in the alloy; (2) Planing the surface of the ingot after electron beam melting, and then forging it into the specifications of the vacuum consumable furnace electrode, and turning the surface oxide scale; (3) melting the electrode three times in a vacuum consumable arc furnace to obtain a three-melting ingot; (4) After the surface of the ingot is peeled, it is ultrasonically inspected, the head riser is removed, and multiple-fire forging is performed to roll it into the required specifications; (5) The finished product after rolling is subjected to solution aging heat treatment to obtain a high-hardness titanium-zirconium alloy.

7. The method for preparing a high-hardness titanium-zirconium alloy material according to claim 6, characterized in that: The forging temperature in step (2) is 1100-1200° C., and the holding time is 200-300 minutes.

8. The method for preparing a high-hardness titanium-zirconium alloy material according to claim 6, characterized in that: The rolling temperature described in step (4) is 980-1100°C.

Images