Free-machining titanium material and preparation process therefor

Abstract

The present invention relates to the technical field of other processing of metals. Disclosed are a free-machining titanium material and a preparation process therefor. The free-machining titanium material comprises: a matrix component group and free-machining component groups, wherein at least one of the free-machining component groups is added to the matrix component group; the matrix component group comprises the following components in percentage by mass: 0-1.0% of Fe, 0-0.08% of N, 0-0.02% of H, 0-0.50% of O, 0-8.0% of Al, 0-15.0% of V, and the balance being titanium and inevitable impurities; and the free-machining component groups are an RE element and S element group, a Cu element and S element group, a Zr element group, a C element group, a B element group, and an Mg element group, respectively. The preparation process involves producing the described free-machining titanium material by using any one of the following three methods: vacuum arc remelting, vacuum floating melting, and powder metallurgy. The present invention solves the technical problem of how to further improve the machinability of titanium materials.

Description

A free-cutting titanium material and a preparation process thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of other processing of metals, and in particular to a free-cutting titanium material and a preparation process thereof. BACKGROUND

[0002] Among the categories of non-ferrous metals, the performance of titanium is particularly excellent; it is considered as an important strategic material due to its high specific strength, wear resistance, high temperature resistance, corrosion resistance and other advantages; thus, it is widely used in the fields of aerospace, ocean engineering, automobile industry and the like. However, the poor cutting performance of titanium material has been a major difficulty in restricting its engineering application when it is mechanically processed.

[0003] Specifically, the reasons for the poor cutting performance of titanium material mainly include the following aspects: the high strength and hardness of titanium, poor thermal conductivity; the hardening phenomenon is serious when it is mechanically processed. At the same time, due to the high chemical activity of titanium, it reacts with various gases in the air during processing and thus easily forms a so-called "microstructure hardening layer" on the surface; thus, the cutting force on the tool during cutting is very large, which causes severe tool wear and easy tool breakage. In addition, the thermal conductivity of titanium is low, which is only one fourth of the thermal conductivity of iron; thus, the heat generated during the cutting of titanium material is almost present on the cutting edge of the tool and cannot be discharged, which leads to high temperature in the cutting zone during cutting and severe tool wear. In addition, the elastic modulus of titanium is small, and the deformation during processing is large and easy to rebound, which not only further aggravates the degree of tool wear; but also seriously affects the surface precision of the processed parts. Further, the friction coefficient between titanium and the tool is large, and the tool sticking phenomenon easily occurs during cutting, so that the heat generated during the cutting of titanium material is concentrated on the cutting edge, which also aggravates the degree of tool wear.

[0004] In summary, the aforementioned many unfavorable factors make the cutting performance of titanium material poor, which not only increases the processing cost of titanium material, but also makes the precision of the parts cannot be guaranteed, and thus greatly limits the commercialization and application of titanium material.

[0005] For the existing technical solutions, in order to solve the technical problem of difficult cutting of titanium material, it can be started from the following two aspects: improving the processing conditions of titanium material and alloying titanium material. Improving the processing conditions of titanium material means improving the cutting performance of titanium material by developing high-performance tool materials and cutting fluids. Alloying titanium material means improving its cutting performance by controlling the microstructure of titanium material. It should be pointed out that in some specific application fields of titanium material, alloying is the only choice to improve the cutting performance of titanium material.

[0006] Based on this, Chinese patent CN102605212A discloses an easy-to-cut titanium alloy and a preparation method thereof. The Ti, Cu and Cr powders are mixed in a certain proportion, and then an easy-to-cut titanium alloy is prepared by a powder metallurgy method. The titanium alloy prepared in this way has the advantages of high strength, low elastic modulus and excellent cutting performance. The main technical means for improving the cutting performance is to add Cu with high thermal conductivity to the titanium material, and to generate the easy-to-cut Ti2Cu phase.

[0007] In addition, another Chinese patent CN102719701A also discloses an easy-to-cut titanium alloy and a preparation method thereof. A titanium alloy with excellent cutting performance is prepared by a vacuum self-consumption smelting method. The titanium alloy has good fatigue strength and hot working performance. The composition of the titanium alloy prepared in this way includes Ti, C, Fe, N, H, Al, V, O and RE elements. In addition, easy-to-cut components are added, including Bi, Sn, Te, P, Ni, S and other elements.

[0008] Further, another Chinese patent CN108097739A also discloses a processing method of easy-to-cut TC4 alloy wire. First, TC4 ingot with a nickel content of 0.5%-2% is prepared from sponge titanium, industrial pure aluminum and titanium-nickel alloy wire. Then, TC4 wire is obtained after processing such as forging, rolling, drawing and low-temperature drawing. After corresponding continuous annealing heat treatment of the TC4 wire, an easy-to-cut TC4 titanium alloy wire is obtained. The second phase particles Ti2Ni are generated in the matrix of the easy-to-cut wire. In addition, the large deformation drawing and continuous annealing treatment also refine the internal organization, so that the cutting performance of the wire is more excellent than that of ordinary TC4 wire.

[0009] Further, another Chinese patent CN115652141A also discloses a low-cost easy-to-cut antibacterial titanium alloy and a preparation method of titanium alloy faucet. An easy-to-cut antibacterial titanium alloy is prepared by a vacuum self-consumption smelting method. The specific chemical composition is: C≤0.05%, H≤0.015%, N≤0.05%, O≤0.2%, Al: 10.0-12.0%, Fe: 6.0-10.0%, Mn: 1.0-3.0%, Mo: 0.1-0.5%, Cu: 4.0-6.0%, Bi: 0.5-1.0%, Sn: 0.6-1.5%, and the balance is Ti and unavoidable impurities. The titanium alloy is successfully manufactured into a titanium alloy faucet by a negative pressure casting method. Through the synergistic effect of brittle Ti3Al compound, dispersed bismuth particles and other elements, the titanium alloy has better easy-to-cut technical effect compared with ordinary titanium alloy ZTiAl6V4.

[0010] However, the prior art still has the technical problem that the cutting property of titanium material cannot be significantly improved or titanium material cannot simultaneously have the advantages of easy cutting property, low cost and simple process. SUMMARY

[0011] Therefore, it is necessary to provide an easy-to-cut titanium material and a preparation process thereof for further improving the cutting property of titanium material.

[0012] An easy-to-cut titanium material comprises a base component group and an easy-to-cut component group, at least one of the easy-to-cut component group is added to the base component group.

[0013] The base component group comprises Fe: 0-1.0%, N: 0-0.08%, H: 0-0.02%, O: 0-0.50%, Al: 0-8.0%, V: 0-15.0% by mass, and the balance is titanium and unavoidable impurities.

[0014] The easy-to-cut component group comprises an RE element and S element group, a Cu element and S element group, a Zr element group, a C element group, a B element group or a Mg element group.

[0015] In the RE element and S element group, the RE element is an element with an atomic number of 57-71 and a rare earth alloy formed by the elements; the addition amount of the RE element is 0-4.0% by mass, the addition amount of the S element is 0-1.0% by mass, and the mass ratio of the RE element to the S element satisfies RE element:S element=n:1, wherein n=1-4.

[0016] In the Cu element and S element group, the Cu element is added in the form of Cu powder or copper alloy; the addition amount of the Cu element is 0-4.5% by mass, the addition amount of the S element is 0-1.0% by mass, and the mass relationship between the Cu element and the S element satisfies Cu=3S+m, wherein m=0-1.5%.

[0017] The addition amount of the Zr element group is 0-3.0% by mass; in the Zr element group, the Zr element is added in the form of zirconium titanium alloy, and the mass relationship between the Zr element and the Ti element satisfies Zr=0.048Ti-p, wherein p=0-2.5%.

[0018] The addition amount of the C element group is 0-1.0% by mass; in the C element group, the C element is added in the form of graphite or graphene.

[0019] The addition amount of the B element group is 0-0.5% by mass; in the B element group, the B element is added in the form of pure boron or boron-iron alloy.

[0020] The addition amount of the Mg element group is 0-1.0% by mass, in the Mg element group, the Mg element is added in the form of magnesium-iron alloy or magnesium-aluminum alloy, and the mass relationship between the Mg element and the O element satisfies: Mg=4O+q, wherein q=0-0.05%.

[0021] Further, in another embodiment, the base component group is: Fe: 0-0.500%; N: 0-0.050%; H: 0-0.015%; O: 0-0.400%; Al: 0-4.000%; V: 0-3.000% by mass, and the balance is titanium and unavoidable impurities.

[0022] Further, in another embodiment, in the RE element and S element group, the addition amount of the RE element is 0.5-2.4% by mass, the addition amount of the S element is 0.1-1.0% by mass, and the mass ratio between the RE element and the S element satisfies: RE element:S element=n1:1; wherein n1=1.25-3.00.

[0023] Further, in another embodiment, in the Cu element and S element group, the addition amount of the Cu element is 0.5-2.5% by mass, the addition amount of the S element is 0.1-0.8% by mass, and the mass between the Cu element and the S element satisfies: Cu=3S+m1; wherein m1=0.1-0.9%.

[0024] Further, in another embodiment, the addition amount of the Zr element group and the addition amount of the Ti element satisfy: Zr=0.048Ti-p1 by mass; wherein p1=0-1.3%.

[0025] Further, in another embodiment, the addition amount of the C element group is 0.40-0.65% by mass, and the addition amount of the B element group is 0.002-0.030% by mass.

[0026] Further, in another embodiment, in the Mg element group, the addition amount of the Mg element and the addition amount of the O element satisfy: Mg=4O+q1 by mass; wherein q1=0-0.03%.

[0027] Specifically, in the aforementioned free-cutting titanium material, the RE is added in the form of block or powder rare earth and rare earth alloy during the raw material mixing process, and one element in the rare earth can be added alone, or several elements in the rare earth can be added in combination.

[0028] Specifically, in the aforementioned free-cutting titanium material, the S element adding medium includes sublimed sulfur (sulfur powder), ferrous sulfide (FeS2, FeS, etc.), MoS2, TiS2, or Cu2S, etc.

[0029] Further, in one specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.5%, La: 0.5%, S: 0.3%, Al: 1.6%, V: 2.0%, Fe: 0.15%, and unavoidable impurities, and the mass ratio of La (RE) to S is 1.67:1.

[0030] Further, in another specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.1%, La: 0.6%, S: 0.3%, Al: 4.0%, and unavoidable impurities, and the mass ratio of La (RE) to S is 2:1.

[0031] Further, in another specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.5%, La: 0.5%, S: 0.4%, Al: 1.5%, V: 2.0%, Fe: 0.15%, and unavoidable impurities, and the mass ratio of La (RE) to S is 1.25:1.

[0032] Further, in another specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.1%, La-Ce composite rare earth: 0.9%, S: 0.35%, Al: 3.2%, V: 0.5%, and unavoidable impurities, and the mass ratio of La+Ce (RE) to S is 2.6:1.

[0033] Further, in another specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.4, La-Ce composite rare earth: 1.6%, S: 0.5%, Al: 1.0%, Cu: 1.5%, B: 0.004%, and unavoidable impurities, and the mass ratio of La+Ce (RE) to S is 3.2:1, and the mass ratio of Cu to S is 3:1.

[0034] Further, in another specific embodiment of the free-cutting titanium material, the components are present in the following mass percentages: Ti: 95.4, La-Ce composite rare earth: 1.6%, S: 0.5%, Al: 1.0%, Cu: 1.5%, B: 0.004%, and unavoidable impurities, and the mass ratio of La+Ce (RE) to S is 3.2:1, and the mass ratio of Cu to S is 3:1.

[0035] Further, in another embodiment of the free-cutting titanium material, the components are as follows in terms of mass percentage: Ti: 96.4%, La-Ce composite rare earth: 0.5%, S: 0.15%, Zr: 2.85%, Fe: 0.15%, and unavoidable impurities, the mass ratio of La+Ce (RE) to S is 3.3:1, and the mass ratio of Zr to Ti is 0.03:1.

[0036] Further, in another embodiment of the free-cutting titanium material, the components are as follows in terms of mass percentage: Ti: 98.9%, Ce: 0.5%, S: 0.15%, C: 0.5%, and unavoidable impurities, the mass ratio of Ce to S is 3.3:1.

[0037] Further, in another embodiment of the free-cutting titanium material, the components are as follows in terms of mass percentage: Ti: 95.2%, Mg: 0.8%, O: 0.2%, Al: 1.8%, V: 2.0%, and unavoidable impurities, the mass ratio of Mg to O is 4.1:1.

[0038] Specifically, a process for preparing the free-cutting titanium material is implemented based on a vacuum consumable process, and includes the following steps:

[0039] S11: mixing: the base component groups of the free-cutting titanium material are mixed according to a preset ratio and put into a mixer for sufficient stirring to make the components uniform;

[0040] S12: electrode block preparation: the mixed and uniform base component groups are poured into a mold barrel of an electrode extruder, and the free-cutting components of the free-cutting titanium material are placed in the middle of the mold barrel according to a preset ratio; then, the material in the mold barrel is extruded into an electrode block by the electrode extruder;

[0041] S13: consumable electrode preparation: a preset number of electrode blocks obtained in step S12 are put into a vacuum plasma welding box, and all the electrode blocks are welded into a whole consumable electrode by plasma welding under vacuum conditions, as an anode for vacuum consumable smelting;

[0042] S14: primary vacuum consumable smelting: the consumable electrode is clamped by a clamp and then put into a water-cooled copper crucible, and after the vacuum degree in the furnace is less than 3 Pa, the power is turned on; after the power is turned on, the electrode tip arcs, and under the action of high temperature, the electrode starts to melt and the melt drops into the crucible, and the molten pool gradually rises to form an ingot; the smelting voltage is set to 20-30 V, and the smelting current is set to 2-6 KA, to obtain a primary smelting ingot;

[0043] S15: Surface turning of the consumable ingot: the surface of the smelted ingot is turned to remove the surface skin containing defects, and the smelted titanium ingot with the skin defects removed is obtained after the treatment;

[0044] S16: Multiple smelting: the smelted ingot obtained in one time is subjected to steps S14 and S15 again, and refined at least twice to obtain the refined free-cutting titanium alloy ingot.

[0045] 0031. Specifically, another process for preparing the aforementioned free-cutting titanium material is realized based on a vacuum suspension smelting process, which comprises the following steps:

[0046] S21: Mixing: the raw materials of the base component group and the raw materials of the free-cutting component group of the free-cutting titanium material are mixed in a predetermined ratio and put into a mixer;

[0047] S22: Feeding: the mixed raw materials of the base component group and the free-cutting component group are respectively fed into the crucible of the vacuum suspension smelting furnace by a feeder, and the raw materials of the free-cutting component group are placed in the middle of the crucible, so that the raw materials of the free-cutting component group are wrapped in the middle of the raw materials of the base component group;

[0048] S23: Gas washing after vacuum treatment: the vacuum suspension smelting furnace is vacuumized to 1x10 -3 Pa or below, and a predetermined vacuum degree is maintained;

[0049] S24: One-time smelting: the voltage and current are adjusted according to the size of the titanium material to be prepared, so that the temperature in the furnace is increased to 1700-2300℃, and after the alloy is completely melted, the temperature is maintained for 10 min, and the free-cutting titanium ingot is obtained after the initial smelting;

[0050] S25: Multiple smelting: the free-cutting titanium ingot after the initial smelting is subjected to up-down material stirring, repeated furnace charging and smelting, and smelted for three times or more to ensure the uniformity of the structure and composition of the titanium ingot.

[0051] 0032. Specifically, another process for preparing the aforementioned free-cutting titanium material is realized based on a powder metallurgy process, which comprises the following steps:

[0052] S31: Mixing: the raw materials of the base component group and the raw materials of the free-cutting component group of the free-cutting titanium material are mixed in a predetermined ratio and put into a mixer, and the particle size of the raw materials of the free-cutting component group is close to that of the raw materials of the base component group, and then the mixture is stirred sufficiently to make the components uniform;

[0053] S32: Ball milling treatment: the mixed powder is subjected to ball milling under the protection of argon, wherein the ball-to-material ratio is set to 3:1-14:1, and the ball milling time is set to 1-6h;

[0054] S33: Compaction: the raw material after ball milling is compacted at a pressure of 200-800 MPa;

[0055] S34: Sintering: the raw material after compaction is vacuum sintered, the vacuum degree is controlled to be less than 0.1 Pa; the raw material is heated to 1000-1400℃ at a heating rate of 4-10℃ / min from room temperature, then heated to 1150-1650℃ at a heating rate of 2-5℃ / min and kept for 2-3 h;

[0056] S35: Cooling: the power is turned off after the keeping is finished, the raw material is cooled in the furnace, when the furnace is cooled to 750℃, inert gas is introduced into the furnace for air cooling, the sintered blank of titanium material is obtained after air cooling to below 50℃.

[0057] In summary, titanium material is regarded as an important strategic material due to its light specific gravity, high strength, wear resistance, high temperature resistance and corrosion resistance, and is widely used in the fields of aerospace, marine engineering, automobile industry and the like. However, the titanium material has the defect of poor machinability, which has always been a big difficulty in restricting its engineering application. The easy-to-cut titanium material and the preparation process thereof disclosed by the present application can obviously improve the cutting performance of the titanium material by adding one or more groups of easy-to-cut components to the base component of the titanium material. The easy-to-cut titanium material has the advantages of simple component design, low cost, simple process, strong operability and suitability for the preparation of various titanium materials. Compared with the traditional titanium material, the cutting efficiency of the easy-to-cut titanium material disclosed by the present application can be improved by more than 30%; therefore, the titanium material not only has the advantage of good cutting performance, but also has good hot workability and cold deformation performance, so that the applicability is strong. Therefore, the easy-to-cut titanium material and the preparation method thereof disclosed by the present application solve the technical problem of how to further improve the easy-to-cut performance of the titanium material. BRIEF DESCRIPTION OF DRAWINGS

[0058] FIG. 1 is a metallographic photo of Example 1 of the easy-to-cut titanium material disclosed by the present application;

[0059] FIG. 2 is a metallographic photo of Comparative Example 1 compared with Example 1;

[0060] FIG. 3 is a metallographic photo of Example 2 of the easy-to-cut titanium material disclosed by the present application;

[0061] FIG. 4 is a metallographic photo of Comparative Example 2 compared with Example 2;

[0062] FIG. 5 is a metallographic photo of Example 3 of the easy-to-cut titanium material disclosed by the present application;

[0063] FIG. 6 is a metallographic photo of Comparative Example 3 compared with Example 3;

[0064] FIG. 7 is a photomicrograph of Example 4 of the disclosed free machining titanium alloy;

[0065] FIG. 8 is a photomicrograph of Comparative Example 4 as compared to Example 4;

[0066] FIG. 9 is a photomicrograph of Example 5 of the disclosed free machining titanium alloy;

[0067] FIG. 10 is a photomicrograph of Comparative Example 5 as compared to Example 5;

[0068] FIG. 11 is a photomicrograph of Example 6 of the disclosed free machining titanium alloy;

[0069] FIG. 12 is a photomicrograph of Comparative Example 6 as compared to Example 6;

[0070] FIG. 13 is a photomicrograph of Example 7 of the disclosed free machining titanium alloy;

[0071] FIG. 14 is a photomicrograph of Comparative Example 7 as compared to Example 7;

[0072] FIG. 15 is a photomicrograph of Example 8 of the disclosed free machining titanium alloy;

[0073] FIG. 16 is a photomicrograph of Comparative Example 8 as compared to Example 8;

[0074] FIG. 17 is a photomicrograph of Example 9 of the disclosed free machining titanium alloy;

[0075] FIG. 18 is a photomicrograph of Comparative Example 9 as compared to Example 9;

[0076] FIG. 19 is a schematic diagram of a test system for testing the cutting performance of the disclosed free machining titanium alloy;

[0077] FIG. 20 is a graph of the test results obtained from cutting force testing of Example 1 using the cutting performance test system. DETAILED DESCRIPTION

[0078] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. It will be apparent, however, to one skilled in the art that the present application can be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the present application. The specific embodiments of the present application are not intended to be limiting, and the scope of the present application is to be determined by the appended claims.

[0079] In addition, the terms "first", "second", "third", etc. are used herein for descriptive purposes only and should not be construed as indicating or implying relative importance or an ordered sequence. Thus, features having a "first", "second" or "third" designation can include at least one of the features, either explicitly or implicitly.

[0080] In the present application, unless specifically stated and limited otherwise, the terms "mounting", "connecting", "connecting", "fixing" and the like should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integrated; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0081] In the present application, unless specifically stated and limited otherwise, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0082] Specifically, the present application is a free-cutting titanium material, which comprises a base component group and a free-cutting component group, and at least one of the free-cutting component groups is added to the base component group; the base component group comprises, by mass percentage: Fe: 0-1.0%; N: 0-0.08%; H: 0-0.02%; O: 0-0.50%; Al: 0-8.0%; V: 0-15.0%, and the balance is titanium and unavoidable impurities; and the free-cutting component group comprises: a rare earth element (RE) and S element group, a Cu element and S element group, a Zr element group, a C element group, a B element group, and a Mg element group.

[0083] Among them, for the RE element and S element group, the RE element is an element with atomic number 57-71 and a rare earth alloy formed by the mutual combination of the elements; in the RE element and S element group, the content of the RE element is 0-4.0% by mass fraction, and the content of the S element is 0-1.0% by mass fraction, and the mass ratio of the RE element to the S element satisfies: n:1, n=1-4; to ensure that the RE element and the S element can form stable rare earth sulfide, which serves as a free-cutting phase to improve the machinability of the titanium material.

[0084] Specifically, the S element is a free cutting element, and adding the S element to the titanium material is beneficial to increase the chip breaking property of the chip, thereby improving the cutting performance of the titanium material. The mechanism of improving the cutting performance of the titanium material by adding the S element alone is that the S element combines with Ti to form a free cutting phase TiS2, and as the content of the S element in the titanium material increases, the amount of TiS2 increases significantly, which is beneficial to increase the thermal embrittlement of the titanium material and facilitate chip breaking during cutting. Meanwhile, TiS2 can also improve the heat conduction capacity of the titanium material to improve the cutting working condition of the titanium material.

[0085] More specifically, the adding medium of the S element includes sublimed sulfur (sulfur powder), ferrous sulfide (FeS2, FeS, etc.), MoS2, TiS2, and Cu2S, etc.

[0086] Specifically, the RE element is added in the form of block or powder of rare earth and rare earth alloy in the raw material smelting process. The RE element can be one of La, Ce, Pr, and Nd, which is added alone or several of them are added in combination. The RE element and the S element are added in combination to form rare earth sulfide between the RE element and the S element.

[0087] The mechanism of improving the cutting performance of the titanium material by the cooperation of the RE element and the S element is that the rare earth and the sulfur can form rare earth sulfide, and these rare earth sulfides have a relatively fixed ratio, which is beneficial to chip breaking during cutting and can improve the heat conduction capacity of the titanium material. When the content of the RE element and the S element is relatively low, the rare earth sulfide is in the form of small granular spherical precipitation at the grain boundary, and the amount is small, which has a weak effect on improving the cutting performance of the titanium material. When the content of the RE element and the S element is increased, the rare earth sulfide is in the form of cluster spherical precipitation at the grain boundary and in the grain, and the size is large, which has a significant effect on improving the cutting performance of the titanium material. When the content of the RE element and the S element is further increased, the improvement of the cutting performance of the material is limited, but the negative effect on the material is significantly increased.

[0088] Specifically, through metallographic analysis, it is found that when the content of the RE element is 0-4.0%, the content of the S element is 0-1.0%, and the mass of the RE element and the S element satisfies n:1 (n=1-4), that is, when the RE content and the S content and the mass ratio of the RE and the S are added according to the present application, the rare earth sulfide can be uniformly distributed in the titanium material, and the morphology is spherical, the amount is large, and the size is small. These uniformly distributed rare earth sulfides are beneficial to the generation of the chip of the titanium material and the segmentation effect, which significantly improves the cutting performance of the titanium material and has no significant effect on other properties of the titanium material.

[0089] Further, for the Cu element and S element group, the Cu element is added in the form of Cu powder or copper alloy; and the content of the Cu element is 0-4.5% by mass, and the content of the S element is 0-1.0% by mass, and the mass of the Cu element and the S element satisfies Cu=3S+m, m=0-1.5%, so as to ensure that the Cu and S elements can form CuTi2 and Cu2S compounds in the titanium material, and the compounds can be used as easy cutting phases to improve the thermal conductivity of the titanium material and improve the thermal workability and cutting property of the material.

[0090] Specifically, the reason why the addition of the Cu element improves the easy cutting property of the titanium material is that the Cu itself has high thermal conductivity, and the addition of the Cu in the titanium material is beneficial to the conduction of heat in the cutting area during cutting; when the Cu and S are added together, the Cu and S can form easy cutting phases that are beneficial to cutting, and the addition of the Cu in the titanium material can form a brittle phase Ti2Cu, and the Ti2Cu phase can be used as a chip breaking source to further improve the cutting workability of the titanium material.

[0091] It should be noted that when the addition amount of the Cu is low, the CuTi2 and Cu2S compounds formed in the titanium material are less, and the improvement of the cutting property of the titanium material is not obvious; when the content of the Cu is 0-4.5% and the content of the S is 0-1.0%, and the mass of the Cu and the S satisfies Cu=3S+m, m=0-1.5%, that is, when the Cu content and the S content and the mass ratio of the Cu and the S are added according to the disclosure, stable and uniform CuTi2 and Cu2S compounds can be formed in the titanium material, which not only enhances the thermal conductivity of the titanium material, but also improves the chip segmentation rate of the titanium material during cutting, and can significantly improve the cutting property of the titanium material, and has little effect on other properties of the titanium material. When the content of the Cu and the S is further increased, a large amount of CuTi2 and Cu2S compounds will be precipitated in the titanium material and distributed in the titanium material, which will seriously deteriorate the high-temperature performance of the titanium material.

[0092] Further, for the Zr element group, the content of the Zr element group is 0-3.0% by mass, wherein the Zr element is added in the form of a zirconium-titanium alloy, and the Zr element and the Ti element satisfy Zr=0.048Ti-p, p=0-2.5%, so as to ensure that the Zr element can be effectively solid-solved in the titanium material and precipitated at the grain boundary; and the thermal workability and cutting workability of the titanium material can be improved.

[0093] Specifically, Zr can be solid-solved in titanium material, the relative atomic mass of Zr is 91.2, and the relative atomic mass of Ti is 47.9; in order to make Zr completely solid-solved in titanium, and the excess Zr atoms precipitate in the form of ZrTi compound in the titanium material, the mass between Zr and Ti should satisfy: 47.9Zr*40=91.2Ti-p, wherein: p=0~2.5%; when the addition amount of Zr is low, Zr is completely solid-solved in Ti, and has no effect on improving the cutting performance of titanium material; when the content of Zr is high, ZrTi compound precipitates in large quantities, which is not conducive to the cutting performance of titanium material.

[0094] Further, for the C element group, the content of the C element group is 0~1.0% by mass; C is added in the form of graphite or graphene, and C precipitates in the form of TiC in the titanium material as a precipitate phase. Thus, the grain boundary can be pinned and the grain can be refined during high-temperature hot working, so as to improve the thermal conductivity of the titanium material and further improve the cutting machinability of the titanium material.

[0095] When the content of C is low, C is solid-solved in Ti and cannot form TiC precipitate phase, which cannot improve the cutting performance of the titanium material. When the content of C is high, a large amount of TiC inclusions will be formed in the titanium material and distributed in the titanium material, which will seriously affect the plasticity of the titanium material and embrittle the titanium material. At the same time, it will also exacerbate the wear of the cutting tool during cutting machining. When the addition amount of C is 0~1.0%, TiC can be uniformly precipitated in the titanium material, and a large amount of fine TiC can not only improve the thermal conductivity of the titanium material, but also have the effects of pinning the grain boundary and refining the grain, which is beneficial to improve the cutting machinability of the titanium material.

[0096] Further, for the B element group, the content of the B element group is 0~0.5% by mass. Among them, B is added in the form of pure boron or boron-iron alloy to ensure that B atoms can be solid-solved in the titanium material, thereby inhibiting the grain growth behavior of the titanium material during high-temperature hot working, and having the effects of refining the grain and uniformizing the structure, so as to improve the cutting machinability of the titanium material.

[0097] Specifically, B can be solid-solved in titanium material, therefore, when the addition amount of B is low, B is completely solid-solved in titanium material, and cannot have a more ideal improvement effect on the cutting performance. When the addition amount of B is too high, hard borides TiB and TiB2 precipitate in large quantities, which further deteriorates the cutting performance of the titanium material, and also exacerbates the wear of the cutting tool. When the addition amount of B is 0~0.5%, on the one hand, it can ensure that B atoms can be solid-solved in the titanium material, and on the other hand, it can also make borides precipitate in the titanium material, which not only has the effects of pinning the grain boundary, refining and uniformizing the structure, but also can improve the cutting performance of the titanium material.

[0098] Further, for the Mg element group, the content of the Mg element group is 0-1.0% by mass, wherein the Mg element is added in the form of a magnesium-iron alloy or a magnesium-aluminum alloy, and the addition amount of the Mg element satisfies Mg=40+q, wherein q=0-0.05%, so as to ensure that MgO is formed in the titanium material during smelting, and the MgO is dispersedly distributed as a precipitated phase, thereby improving the cutting chip breaking property of the material, increasing the heat transfer property, and further improving the cutting machinability of the titanium material.

[0099] Specifically, when the addition amount of Mg is too high, a large amount of MgO with large size and aggregated distribution is formed in the titanium material, which reduces the cutting chip breaking property of the titanium material, and at the same time, the cleanliness of the titanium material is reduced, which seriously deteriorates the mechanical properties of the titanium material. When the addition amount of Mg is low, the Mg is completely solid-solved in the titanium material and cannot improve the cutting performance of the titanium material as an easy-cutting phase. Therefore, when the addition amount of Mg is 0-1.0% and the addition amount of Mg satisfies Mg=40+q, wherein q=0-0.05%, the Mg can combine with O to form MgO. At this time, the MgO is dispersedly distributed in the titanium material as an easy-cutting phase, which significantly improves the cutting chip breaking property of the titanium material; at the same time, the heat transfer property of the titanium material is increased, and the cutting machinability of the titanium material is further improved.

[0100] Further, the foregoing easy-cutting titanium material can be prepared by any one of the following three methods: vacuum self-consumption smelting, vacuum suspension smelting, and powder metallurgy.

[0101] Specifically, when the foregoing easy-cutting titanium material is prepared by the method of vacuum self-consumption smelting, the preparation process includes the following steps:

[0102] S11: mixing: the base component groups of the easy-cutting titanium material are mixed according to the preset ratio and put into a mixer for sufficient stirring, so that the components are uniform;

[0103] S12: electrode block preparation: the mixed and uniform base component groups are poured into a mold barrel of an electrode extruder, and the easy-cutting components of the easy-cutting titanium material are placed in the middle part of the mold barrel according to the preset ratio; then, the material in the mold barrel is extruded into an electrode block by the electrode extruder;

[0104] S13: self-consumption electrode preparation: a preset number of electrode blocks in step S12 are put into a vacuum plasma welding box, and all the electrode blocks are welded into a whole self-consumption electrode by plasma welding under vacuum conditions, which serves as an anode for vacuum self-consumption smelting;

[0105] S14: Once vacuum consumable melting: after the consumable electrode is clamped by the clamp, it is put into the water-cooled copper crucible, vacuum is drawn to make the vacuum degree in the furnace less than 3 Pa, and then power is turned on; after the arc is started at the end of the electrode, the electrode starts to melt under the action of high temperature and the melt drops into the crucible, the molten pool gradually rises to form an ingot; the melting voltage is set to 20-30 V, the melting current is set to 2-6 KA, and the initially refined consumable ingot is obtained;

[0106] S15: Surface turning of the initially refined consumable ingot: the surface of the melted ingot is turned to remove the skin containing defects, and the melted titanium ingot with the skin defects removed is obtained after processing;

[0107] S16: Multiple melting: the melted ingot obtained once is subjected to steps S14 and S15 again, and refined at least twice to obtain a refined free-cutting titanium alloy ingot. Specifically, the multiple melting is a further refining based on the initial melting, so as to improve the uniformity of the alloy elements in the titanium alloy ingot and remove the surface impurity elements, and ensure the consistency of the material.

[0108] Further, when the aforementioned free-cutting titanium material is prepared by using the vacuum floating melting method, the preparation process comprises the following steps:

[0109] S21: Mixing: the base component groups of the free-cutting titanium material are mixed according to the preset ratio and put into a mixer;

[0110] S22: Feeding: the raw materials of the base component groups and the raw materials of the free-cutting component groups of the free-cutting titanium material in the preset ratio are fed into the crucible of the vacuum floating melting furnace by using a feeder, and the raw materials of the free-cutting component groups are placed in the middle of the crucible and wrapped in the middle by the raw materials of the base component groups;

[0111] S23: Gas washing after vacuum treatment: the vacuum floating melting furnace is vacuumed to 1x10 -3 Pa or below, and a preset vacuum degree is maintained;

[0112] S24: Once melting: according to the size of the titanium material to be prepared, the voltage and current are adjusted respectively to make the temperature in the furnace rise to 1700-2300℃, and after the alloy is completely melted, the temperature is maintained for 10 min, and the initially refined free-cutting titanium ingot is obtained;

[0113] S25: Multiple melting: the initially refined free-cutting titanium ingot is subjected to up-down material turning, repeated furnace charging and melting, and is melted for three times or more to ensure the uniformity of the structure and composition of the titanium ingot.

[0114] 0060. Further, when the aforementioned free-cutting titanium material is prepared by using the powder metallurgy method, the preparation process comprises the following steps:

[0115] S31: mixing: the raw materials of the base component group and the easy cutting component group are mixed in proportion, and the particle size of the easy cutting component group is made as close as possible to that of the raw materials of the base component group, and the components are uniformly stirred;

[0116] S32: ball milling treatment: the mixed powder is ball milled under the protection of argon, the ball-to-material ratio is set to 3:1-14:1, and the ball milling time is set to 1-6 h;

[0117] S33: compacting: the raw materials after ball milling are compacted under a pressure of 200-800 MPa;

[0118] S34: sintering: the raw materials after compacting are vacuum sintered, the vacuum degree is controlled to be less than 0.1 Pa, the temperature is raised from room temperature to 1000-1400℃ at a heating rate of 4-10℃ / min, then the temperature is raised to 1150-1650℃ at a heating rate of 2-5℃ / min, and then the temperature is kept constant for 2-3 h;

[0119] S35: cooling: after the temperature keeping is finished, the power is turned off, the raw materials are cooled in the furnace, when the furnace is cooled to 750℃, inert gas is introduced into the furnace for air cooling, and the titanium material sintered compact is obtained after air cooling to below 50℃.

[0120] Specifically, the RE, S, Cu, Zr, C, B and Mg disclosed in the easy cutting titanium material and the preparation process thereof are all elements beneficial to cutting, and the addition of these elements in the titanium material is beneficial to the improvement of the cutting performance of the titanium material.

[0121] Particularly, in one embodiment of the easy cutting titanium material, the base component group is further optimized in mass percentage as follows: Fe: 0-0.5%; N: 0-0.05%; H: 0-0.015%; O: 0-0.4%; Al: 0-4.0%; V: 0-3.0%; and the balance is titanium and unavoidable impurities. In addition to the above components, one or more easy cutting component groups should be contained.

[0122] Particularly, in another embodiment of the easy cutting titanium material, as an easy cutting titanium material containing RE and S, the RE and S are further optimized in mass percentage as follows: the RE content is 0.5-2.4%; the S element content is 0.1-1.0%; and the mass of RE and S should satisfy: RE:S=n1:1, wherein n1=1.5-3.0.

[0123] Particularly, in another embodiment of the present application, the free-cutting titanium material is a free-cutting titanium material containing Cu and S, and the mass percentage of Cu and S is further optimized as follows: Cu: 0.5-2.5%; S: 0.1-0.8%, and the mass of Cu and S satisfies the following equation: Cu=3S+m1, wherein m1=0.1-0.9%.

[0124] Particularly, in another embodiment of the present application, the free-cutting titanium material is a free-cutting titanium material containing Zr, and the addition amount of Zr satisfies the following equation with respect to Ti: Zr=0.048Ti-p1, wherein p1=0-1.3%, so as to ensure that Zr can be effectively solid-solved in the titanium material and precipitated at the grain boundary.

[0125] Particularly, in another embodiment of the present application, the free-cutting titanium material is a free-cutting titanium material containing C, and the mass percentage of C is further optimized as follows: C: 0.40-0.65%, so as to ensure that C is precipitated in the titanium material in the form of TiC and can pin the grain boundary and refine the grain during high-temperature hot working.

[0126] Particularly, in another embodiment of the present application, the free-cutting titanium material is a free-cutting titanium material containing B, and the mass percentage of B is further optimized as follows: B: 0.002-0.030%.

[0127] Particularly, in another embodiment of the present application, the free-cutting titanium material is a free-cutting titanium material containing Mg, and the mass percentage of Mg is further optimized as follows: the mass of Mg and O satisfies the following equation: Mg=4O+q1, wherein q1=0.01-0.03%.

[0128] Further, the following respectively discloses nine specific embodiments and nine corresponding setting comparative examples in terms of mass percentage, and the details are shown in Table 1 as follows:

[0129] Table 1: Chemical composition of different embodiments and comparative examples

[0130] RESCuZrBCMgAlVOFeTi Example 1 0.5*0.3-----1.6 2.0-0.15 Balance Comparative Example 1-------1.6 2.0-0.15 Balance Example 2 0.6*0.3-----4.0---- Balance Comparative Example 2------4.0--- Balance Example 3 0.5*0.4-----1.5 2.0-0.15 Balance Comparative Example 3-------1.5 2.0-0.15 Balance Example 4 0.9**0.35-----3.2 0.5-- Balance Comparative Example 4-------3.2 0.5-- Balance Example 5 1.6**0.51 0.5 - 0.004 - 1.0 - Balance Comparative Example 5 - 1.0 - Balance Example 6 2.4** 0.8 - 0.004 - 3.0 1.0 - Balance Comparative Example 6 - 3.0 1.0 - Balance Example 7 0.5** 0.15 - 2.85 - 0.15 - Balance Comparative Example 7 - 0.15 - Balance Example 8 0.5*** 0.15 - 0.5 - Balance Comparative Example 8 - Balance Example 9 - 0.8 1.8 2.0 0.2 - Balance Comparative Example 9 - 1.8 2.0 0.2 - Balance

[0131] It should be noted that in Table 1 above, * represents the added La content; ** represents the La-Ce composite addition amount; *** represents the added Ce content; and the smelting method used in each embodiment and comparative example is the vacuum consumable melting method.

[0132] Furthermore, the performance of each embodiment and comparative example disclosed in Table 1 of this invention was tested using the following method, and the cutting effect of each embodiment and comparative example is compared in Table 2 below.

[0133] Hardness testing: The hardness of each embodiment and comparative example was tested using an MH-5L micro Vickers hardness tester. A total of 10 tests were conducted, and the average hardness value was selected as the final test result.

[0134] Cutting performance test: The milling cutter was a 4 mm diameter titanium alloy cutting standard cutter - D0101.002027, the cutting fluid was a titanium alloy-specific microemulsion cutting fluid, the spindle speed was 5000 rev / min, the feed rate was 800 mm / min, the depth of cut was 4 mm, and the side depth of cut was 0.4 mm. The cutting performance test was conducted on a V-8L machining center, and the cutting forces during the milling process were collected using a Kistler 9257B force gauge.

[0135] Specifically, please refer to FIG. 19, a system for testing cutting performance, which comprises a testing machining center 1, a titanium alloy milling standard tool 2, a clamp 3, a dynamometer 4, a charge amplifier 5, a data acquisition system 6 and a computer 7; the titanium alloy milling standard tool 2, the clamp 3 and the dynamometer 4 are arranged in the testing machining center 1 respectively, and the dynamometer 4 is connected below the clamp 3. The charge amplifier 5 is connected with the dynamometer 4 through a connecting cable; the data acquisition system 6 is connected with the charge amplifier 5 and the computer 7 respectively. Thus, in the experiment of testing cutting performance, the titanium alloy milling standard tool 2 is driven by the testing machining center 1 to mill a titanium sample piece clamped on the clamp 3 according to preset machining parameters; at this time, the dynamometer 4 can collect cutting force in the milling process; after processing by the charge amplifier 5 and the data acquisition system 6, the data is transmitted to the computer 7 for processing. Please continue to refer to FIG. 20, which shows the cutting force test results obtained after the milling performance test of Example 1 using the aforementioned system for testing cutting performance.

[0136] The performance test results of each example and comparative example are shown in Table 2; the metallographic photos of each example and comparative example after polishing are shown in FIGS. 1-18. Compared with the corresponding comparative example, the titanium material in each example disclosed by the present application introduces a beneficial cutting phase after alloying, which significantly improves the cutting performance of the titanium material.

[0137] Table 2: Cutting effect of each example and comparative example

[0138]

[0139] From the test results in Table 2, it can be seen that the cutting effect of the titanium material can be significantly improved after adding the easy-to-cut component; among them, the calculation method of the cutting force improvement rate disclosed in Table 2 is: cutting force improvement rate (%) = (comparative example cutting force - example cutting force) / comparative example cutting force x 100%.

[0140] In summary, titanium material is regarded as an important strategic material due to its light specific gravity, high strength, wear resistance, high temperature resistance and corrosion resistance, and is widely used in the fields of aerospace, marine engineering, automobile industry, etc. However, the poor machinability of titanium material has always been a major difficulty restricting its engineering application. The present application discloses an easy-to-cut titanium material and a preparation process thereof. By adding one or several groups of easy-to-cut components to the base component of the titanium material, the cutting performance of the titanium material can be significantly improved. The easy-to-cut titanium material has the advantages of simple component design, low cost, simple process, strong operability, and is suitable for the preparation of various titanium materials. Compared with traditional titanium materials, the cutting efficiency of the easy-to-cut titanium material disclosed in the present application can be improved by more than 30%. Therefore, the titanium material not only has good cutting performance, but also has good hot working and cold deformation performance, so its applicability is strong. Therefore, the present application solves the technical problem of how to further improve the easy-to-cut performance of titanium material.

[0141] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present application.

[0142] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. An easy-to-cut titanium material, characterized by comprising, in mass %, It includes: The base component group and the free cutting component group; The base component group is 0~1.0% by mass percentage; N: 0~0.08%; H: 0~0.02%; O: 0~0.50%; Al: 0~8.0%; V: 0~15.0%, the balance is titanium and unavoidable impurities; The free cutting component group includes RE element and S element group, in addition, the free cutting component group also includes at least one of Cu element and S element group, Zr element group, C element group or B element group; In the RE element and S element group, the RE element is a composite rare earth component composed of two or more elements with atomic numbers of 57~71; the addition amount of the RE element is 0.5~2.4% by mass percentage, the addition amount of the S element is 0.1~1.0%, and the mass ratio of the RE element to the S element satisfies: RE element:S element=n1:1; wherein n1=1.25~3.20; In the Cu element and S element group, the Cu element is added in the form of Cu powder or copper alloy; the addition amount of the Cu element is 0.5~2.5% by mass percentage; the addition amount of the S element is 0.1~0.8%, and the mass relationship between the Cu element and the S element satisfies: Cu=3S+m1; wherein m1=0~1.5%; The addition amount of the Zr element group is 0~3.0% by mass percentage; in the Zr element group, the Zr element is added in the form of zirconium titanium alloy, and the mass relationship between the Zr element and the Ti element satisfies: Zr=0.048Ti-p, wherein p=0~2.5%; The addition amount of the C element group is 0~1.0% by mass percentage; in the C element group, the C element is added in the form of graphite or graphene; The addition amount of the B element group is 0~0.5% by mass percentage; in the B element group, the B element is added in the form of pure boron or boron iron alloy.

2. A process for producing a free machining titanium material as claimed in claim 1, characterised in that, Based on the vacuum consumable process, it includes the following steps: S11: mixing: mix the base component group of the free cutting titanium material according to the preset ratio and put it into the mixer for sufficient stirring to make the components uniform; S12: electrode block preparation: first pour the mixed base component group into the mold barrel of the electrode extruder, then place the free cutting component group of the free cutting titanium material in the middle of the mold barrel according to the preset ratio; then, use the electrode extruder to extrude the material in the mold barrel into an electrode block; S13: consumable electrode preparation: put the preset number of electrode blocks obtained in step S12 into a vacuum plasma welding box, and use plasma welding to weld all the electrode blocks into a whole consumable electrode under vacuum conditions as the anode of vacuum consumable smelting; S14: Vacuum consumable melting: After the consumable electrode is clamped by the clamp, it is placed in a water-cooled copper crucible, vacuum is drawn to make the vacuum degree in the furnace less than 3 Pa, and then power is turned on; after the electrode end arcs, the electrode starts to melt under the action of high temperature and the melt drops into the crucible, the molten pool gradually rises to form an ingot; the melting voltage is set to 20-30 V, the melting current is set to 2-6 KA, and an initially refined consumable ingot is obtained; S15: Surface turning of the initially refined consumable ingot: The surface of the melted ingot is turned to remove the skin containing defects, and a melted titanium ingot with skin defects removed is obtained after processing; S16: Multiple melting: The melted ingot obtained once is subjected to steps S14 and S15 again, and is refined at least twice to obtain a refined free-cutting titanium alloy ingot.

3. A process for producing a free machining titanium material as claimed in claim 1, wherein Based on the vacuum suspension melting process, it includes the following steps: S21: Mixing: The raw materials of the base component group and the raw materials of the free-cutting component group of the free-cutting titanium material are mixed according to the preset ratio and put into the mixer; S22: Feeding: The raw materials of the base component group and the raw materials of the free-cutting component group after mixing are fed into the crucible of the vacuum suspension melting furnace by the feeder, and the raw materials of the free-cutting component group are placed in the middle of the crucible, and the raw materials of the free-cutting component group are wrapped in the middle of the raw materials of the base component group; S23: Post-vacuum treatment gas washing: The vacuum suspension smelting furnace is vacuumed to 1 x 10 -3 Pa, and the preset vacuum degree is maintained; S24: Primary melting: According to the size of the titanium material to be prepared, the voltage and current are adjusted respectively to make the temperature in the furnace rise to 1700-2300℃, and after the alloy is completely melted, it is kept for 10 min to obtain an initially refined free-cutting titanium ingot; S25: Multiple melting: The initially refined free-cutting titanium ingot is subjected to up-down stirring and repeated furnace charging and melting, and is melted for three times or more to ensure the uniformity of the structure and composition of the titanium ingot.

4. A process for producing a free machining titanium material as claimed in claim 1, wherein Based on the powder metallurgy process, it includes the following steps: S31: Mixing: The raw materials of the base component group and the raw materials of the free-cutting component group of the free-cutting titanium material are mixed according to the preset ratio and put into the mixer, and the particle size of the raw materials of the free-cutting component group is close to that of the raw materials of the base component group, and then the mixture is stirred thoroughly to make the components uniform; S32: Ball milling treatment: The mixed powder is ball milled under the protection of argon, wherein the ball-to-material ratio is set to 3:1-14:1, and the ball milling time is set to 1-6 h; S33: Compacting: The raw materials after ball milling are compacted under a pressure of 200-800 MPa; S34: Sintering: After compacting, the raw materials are vacuum sintered, the vacuum degree is controlled to be less than 0.1 Pa, the temperature is raised to 1000-1400℃ at a heating rate of 4-10℃ / min from room temperature, then the temperature is raised to 1150-1650℃ at a heating rate of 2-5℃ / min, and then the temperature is kept for 2-3 h; S35: Cooling: After the temperature keeping is completed, the power is turned off, the raw materials are cooled in the furnace, and when the furnace is cooled to 750℃, inert gas is introduced into the furnace for air cooling, and the titanium material sintered compact is obtained after air cooling to below 50℃.

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