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CN-121988753-A - Method for preparing Ti-V-O titanium alloy piece through selective laser melting forming technology

CN121988753ACN 121988753 ACN121988753 ACN 121988753ACN-121988753-A

Abstract

A method for preparing a Ti-V-O titanium alloy piece by a selective laser melting forming technology relates to the technical field of metal material preparation. The invention aims to solve the problem that the elongation is sensitive to oxygen elements in the existing preparation process of the laser selective melting titanium alloy. The method uses micron TiO 2 powder and spherical V powder to carry out cladding by a low-energy ball milling method, and then prepares CP-Ti titanium alloy powder by an argon atomization method, and the CP-Ti titanium alloy powder is uniformly mixed to be used as a raw material for selective laser melting forming so as to ensure the uniformity of the distribution of each element in the powder. And melting and stacking the powder layer by means of selective laser melting equipment to finally obtain the selective laser melting titanium alloy block with excellent mechanical properties. The laser selective melting titanium alloy prepared by the invention does not need subsequent heat treatment, and the elongation percentage in the room temperature mechanical property is improved along with the increase of the V content, so that the common oxygen embrittlement problem of the titanium alloy is avoided. The method is used for preparing the titanium alloy.

Inventors

  • CHEN RUIRUN
  • LI AN
  • WANG QI
  • CHEN DEZHI
  • FANG HONGZE
  • DING XIN

Assignees

  • 哈尔滨工业大学

Dates

Publication Date
20260508
Application Date
20260226

Claims (10)

  1. 1. A method for preparing a Ti-V-O titanium alloy piece by a selective laser melting forming technology is characterized by comprising the following steps: step one, preparing raw materials; Mixing TiO 2 powder and V powder, fully mixing for 6 hours in a planetary ball mill at a rotating speed of 150 rpm, cooling for 10 minutes after 10 minutes of mixing, and continuing mixing; step one, selecting the composite powder in the step one and the CP-Ti titanium alloy powder prepared by an argon atomization method as raw materials for selective laser melting forming, and pouring the composite powder and the CP-Ti titanium alloy powder into a sieve with 300 meshes for sieving; Uniformly mixing the composite powder in the first step and the CP-Ti titanium alloy powder for 6 hours by using a powder mixer, drying, setting the temperature of an oven to be 50 ℃, and keeping the temperature for 3 hours; Converting the three-dimensional model of the target part into two-dimensional slice data, and providing a scanning path basis for layer-by-layer processing for the selective laser melting equipment; step two, building a structural model for the target part according to the requirements; Secondly, two-dimensional slicing is carried out on the established three-dimensional model of the target part; Step two, importing the two-dimensional sliced data into a selective laser melting forming device; Step three, setting processing technological parameters of the selective laser melting processing process, and carrying out selective laser melting processing; Wherein, the processing parameters are that the preset temperature of the substrate is 25 ℃, the laser power is 300-350W, the thickness of the powder layer is 30 mu m, the scanning speed is 1000-1200 mm/s, and the scanning interval is 110 mu m; And fourthly, sequentially performing wire cutting and surface treatment on the processed part, namely removing the support from the part, and performing surface treatment to obtain the Ti-V-O titanium alloy part.
  2. 2. The method for producing a Ti-V-O titanium alloy having strong plasticity synergy by selective laser melting according to claim 1, wherein the CP-Ti titanium alloy powder in step two consists of 3 to 6 wt% of powder having a particle size of less than 15 μm, 1 to 5 wt% of powder having a particle size of more than 53 μm and the balance of powder having a particle size of 15 to 53 μm, resulting in an average particle size of 29.+ -. 9 μm.
  3. 3. The method for preparing the Ti-V-O titanium alloy with strong plasticity synergy through selective laser melting according to claim 2, wherein the apparent density of the CP-Ti titanium alloy powder prepared by the argon atomization method in the step two is 2.0-2.5 g/cm 3 , and the tap density is 2.5-3.0 g/cm 3 .
  4. 4. A method for preparing Ti-V-O titanium alloy with strong plastic matching by selective laser melting according to claim 1 or 3, wherein in the second step, a structural model of a required target part is constructed by using three-dimensional software and stored in STL format, support is added to the constructed model by additive manufacturing processing software, then two-dimensional slicing is carried out, and data after two-dimensional slicing is imported into selective laser melting forming equipment.
  5. 5. The method for preparing the Ti-V-O titanium alloy with strong plasticity matching through selective laser melting according to claim 4, wherein high-purity argon is introduced into the selective laser melting equipment in the selective laser melting processing process in the step three, the selective laser melting equipment is scrubbed by the high-purity argon, and the scrubbing operation reduces the oxygen content in the selective laser melting equipment to below 800 ppm.
  6. 6. The method for preparing Ti-V-O titanium alloy with strong plastic match by selective laser melting of claim 5, wherein TA1 titanium alloy is adopted for the substrate in step three.
  7. 7. The method for preparing the Ti-V-O titanium alloy with strong plastic matching by selective laser melting according to claim 6, wherein the parameters of the selective laser melting equipment in the step three are that the laser power is 300-350W, the powder layer thickness is 30 μm, the scanning speed is 1000-1200 mm/s, the scanning interval is 110 μm, the cross scanning mode is adopted, and the oxygen content in the working bin is less than 800ppm after one layer of horizontal rotation is completed by 67 ° .
  8. 8. The method for preparing the Ti-V-O titanium alloy with strong plastic matching by selective laser melting according to claim 1 or 8, wherein in the fourth step, the surface treatment is sequentially surface cleaning and surface polishing; The surface cleaning process comprises the steps of carrying out ultrasonic cleaning by taking absolute ethyl alcohol as a cleaning medium, wherein the cleaning time is 10 min; The surface polishing process is that sand paper with the surface being smooth and even is sequentially polished on sand paper with the surface being #400, #800, #1000, #2000 and # 3000.
  9. 9. The method for producing a Ti-V-O titanium alloy having a strong plastic match by selective laser melting according to claim 1, wherein the purity of the TiO 2 powder in the step one is > 99.5% and the particle size is 1-5. Mu.m.
  10. 10. The method for producing a Ti-V-O titanium alloy having strong plastic matching by selective laser melting according to claim 9, wherein the purity of V powder in step one is > 99.5% and the particle size is 15-55. Mu.m.

Description

Method for preparing Ti-V-O titanium alloy piece through selective laser melting forming technology Technical Field The invention relates to a method for preparing a Ti-V-O titanium alloy piece, and belongs to the technical field of metal material preparation. In particular to a method for preparing a Ti-V-O titanium alloy piece by ball milling and cladding a trace amount of TiO 2 powder, fully mixing the powder with CP-Ti alloy powder and using a selective laser melting forming technology. By adding TiO 2 and V powder, oxygen and vanadium are combined with a titanium matrix by selective laser melting, so that the internal microstructure of the titanium alloy is changed, and the oxygen embrittlement effect is avoided, so that the alloy has high yield strength and high elongation at room temperature. Background Titanium and its alloys have become key materials in the fields of aerospace, biomedical and the like by virtue of their excellent specific strength, excellent corrosion resistance and good biocompatibility. In the biomedical field, industrial pure titanium (CP-Ti) has excellent corrosion resistance and biocompatibility, but its mechanical strength is relatively low, and there is a risk of fracture under long-term load. To solve the above contradiction, researchers have focused their eyes on gap-strengthening titanium alloys. Oxygen is used as a gap element with rich reserves and low cost, has stronger capability of stabilizing and strengthening alpha-phase titanium than Al element, and can obviously improve the strength of titanium. By adding oxygen element into Ti matrix in the form of interstitial atoms, the mechanical property of titanium can be effectively improved while the excellent biocompatibility and lower cost of titanium are maintained. However, oxygen is considered in conventional wisdom as "the gram of titanium". When the content exceeds a critical value, the brittleness of the titanium alloy is increased sharply, and the plasticity of the titanium alloy is seriously damaged, which greatly limits the practical application of the oxygen-containing titanium alloy. The vanadium element is a traditional titanium alloy beta-phase stabilizing element and has good effect on maintaining strong plasticity. V and O are different due to the mode of strengthening the titanium alloy, so that the strong plasticity of the titanium alloy is cooperatively improved, and the method has good application prospect. The traditional smelting (such as vacuum arc melting) and plastic processing methods for preparing the Ti-V-O alloy also face the problems of high work hardening rate, poor heat conductivity, difficult processing, serious heat accumulation, easy pollution and the like. Selective laser melting (SELECTIVE LASER MELTING, SLM) is used as an advanced powder bed melting additive manufacturing technology, and alloy powder is melted layer by laser beams, so that compact titanium alloy parts with complex geometric shapes can be directly formed. SLM technology provides a new approach to the fabrication of complex, high performance Ti-V-O alloy parts. Although the challenges of air hole defects, residual stress, oxygen embrittlement risk and the like are faced, the comprehensive mechanical properties of the Ti-V-O alloy, particularly strong plastic matching, can be obviously improved by selecting proper oxygen content and printing power, and a sustainable development idea is provided for the titanium alloy in the fields of aerospace lightweight parts and the like. In summary, in the existing preparation process of the laser selective melting titanium alloy, due to the special high cooling rate and heat accumulation effect of the SLM process, the uneven clearance solid solution strengthening and the local embrittlement tendency of oxygen elements are aggravated, so that the problem that the alloy elongation is highly sensitive to the oxygen elements and the comprehensive mechanical property of the Ti-V-O alloy is poor is caused. Disclosure of Invention The invention aims to solve the problem that the elongation is sensitive to oxygen elements in the existing preparation process of the laser selective melting titanium alloy, and further provides a method for preparing a Ti-V-O titanium alloy piece by a selective laser melting forming technology, wherein the alloy strength is improved by preparing V and O doping, and meanwhile, the Ti-V-O titanium alloy with higher elongation is provided. The technical scheme of the invention is as follows: The invention provides a method for preparing a Ti-V-O titanium alloy piece by a selective laser melting forming technology, which comprises the following steps: step one, preparing raw materials; Mixing TiO 2 powder and V powder (purity is more than 99.5 percent and particle size is 15-55 mu m), fully mixing for 6 hours in a planetary ball mill at a rotating speed of 150 rpm, cooling for 10 minutes after 10 minutes of mixing, and continuing mixing; step one, selecting the co