阅读说明：本技术 一种采用电脉冲处理3d打印件的方法 (A method of using Electric Pulse Treatment 3D printing part ) 是由 周乐君 王万林 吴厚发 罗豪 颜雄 于 2019-10-12 设计创作，主要内容包括：一种采用电脉冲处理钛合金3D打印件的方法。本发明公开了一种采用电脉冲处理钛合金3D打印件的方法。本发明所述处理钛合金3D打印件缺陷的电脉冲,其特征在于有效电流密度：15-30A/mm<Sup>2</Sup>,脉冲频率：250-350Hz,脉宽：76-83μS,处理及保温时间：10-30min。本发明所采用的电脉冲处理钛合金3D打印件缺陷的方法,利用电脉冲对材料的高能率加热作用,“电致塑性”作用以及再结晶作用,减少钛合金3D打印件中的孔隙、孔洞等缺陷,改善组织,提高钛合金3D打印件的综合性能。(A method of using Electric Pulse Treatment titanium alloy 3D printing part.The invention discloses a kind of methods using Electric Pulse Treatment titanium alloy 3D printing part.The electric pulse of processing titanium alloy 3D printing part defect of the present invention, it is characterised in that effective current density: 15-30A/mm 2 , pulse frequency: 250-350Hz, pulsewidth: 76-83 μ S, processing and soaking time: 10-30min.The method of Electric Pulse Treatment titanium alloy 3D printing part defect of the present invention, using electric pulse to the high-duty heat effect of material, " Electroplastic " effect and recrystallization, reduce titanium alloy 3D printing part in hole, hole the defects of, improve tissue, improves the comprehensive performance of titanium alloy 3D printing part.)

1. a kind of method using Electric Pulse Treatment 3D printing part, it is characterised in that: adopted after obtaining 3D printing part through 3D printing With Electric Pulse Treatment, finished product is obtained.

2. a kind of method using Electric Pulse Treatment 3D printing part according to claim 1, it is characterised in that: the 3D is beaten Printed document is titanium alloy 3D printing part；The titanium alloy 3D printing part is prepared by following step:

Step 1: prepared by titanium alloy powder,

Using titanium alloy as raw material, prepared sizes are 53-150 μm of spherical powder；

Step 2: titanium alloy 3D printing,

Using spherical powder obtained by step 1 as raw material, titanium alloy 3D printing part is prepared by 3D printing.

3. a kind of method using Electric Pulse Treatment 3D printing part according to claim 1.It is characterized by: when described When 3D printing part is titanium alloy printout, the electric pulse parameter of use are as follows: current density 15-30A/mm², pulsewidth 76-83 μ s, arteries and veins Rush frequency 250-350Hz.

4. a kind of method using Electric Pulse Treatment 3D printing part according to claim 3, it is characterised in that: as the 3D When printout is titanium alloy 3D printing part, the Electric Pulse Treatment parameter of use are as follows: current density 16-21.5A/mm², pulsewidth 76- 80 μ s, pulse frequency 250-300Hz.

5. a kind of method using Electric Pulse Treatment 3D printing part according to claim 4, it is characterised in that: as the 3D When printout is titanium alloy 3D printing part, the Electric Pulse Treatment parameter of use are as follows: current density 21.4-21.5A/mm², pulsewidth 80 μ s, pulse frequency 300Hz.

6. a kind of method using Electric Pulse Treatment 3D printing part according to claim 4, it is characterised in that: as the 3D When printout is titanium alloy 3D printing part, the Electric Pulse Treatment parameter of use are as follows: current density 16.6A/mm², 76 μ s of pulsewidth, arteries and veins Rush frequency 250Hz.

7. a kind of method using Electric Pulse Treatment 3D printing part according to claim 4, it is characterised in that: titanium alloy During 3D printing, laser 3D printing selected parameter is laser power 2000-2200W, scanning speed 400-600mm/s, powder feeding Speed 3-7g/min, overlapping rate 49-51%%, powder feeding gas (Ar) flow 13-17L/min, laser spot diameter 3-5mm and from Coke amount+(4-6) mm.

8. a kind of method using Electric Pulse Treatment 3D printing part according to claim 1, it is characterised in that: titanium alloy 3D During the Electric Pulse Treatment of printout, Electric Pulse Treatment and soaking time 10-30min, air-cooled processing after heat preservation.

9. a kind of method using Electric Pulse Treatment 3D printing part according to claim 2-8, it is characterised in that:, definition The porosity of 3D printing part is A after processing, the porosity of 3D printing part is B before definition process, then [1- (B-A)/B] >=0.45.

Technical field

The present invention relates to a kind of methods using Electric Pulse Treatment titanium alloy 3D printing part；Belong to material increasing field.

Background technique

Since titanium alloy has high specific strength, excellent corrosion resistance and good medium temperature intensity and low-temperature flexibility etc. excellent Point is widely used in aerospace and medical instruments field.But stock utilization when titanium alloy component forming complexity, structure It is low, the period is long, manufactures this height, the application to titanium alloy in aerospace and medical instruments field forms certain restriction.And Machining accuracy that 3D printing has is high, and the process-cycle is short, personalization production, and processing cost is low, high flexibility, highly integrated, printing Can be realized high-performance labyrinth metal parts without mold rapid shaping the advantages that can effectively make up this disadvantage.

Compared with the production method of other titanium alloys, titanium alloy 3D printing has a wide range of application, and has superiority outstanding.But There is also some problems simultaneously: printing since 3D printing is layered, the process principle and titanium alloy powder being layering are quick Melt solidification and a series of reasons such as dusty material internal flaw, can be generated inside titanium alloy stomata, it is highly dense be mingled with, incomplete fusion, The defect of the types such as cold shut defect, unmelted powder particle.These defects make printout internal stress is excessive, hardness not enough and modeling Property reduce, how to carry out the aftertreatment technology of titanium alloy 3D printing, the comprehensive performance for improving printout is extremely crucial.

Laser 3D printing titanium alloy typical organization is made of the substructure of coarse column crystal and transgranular complexity, through difference Tissue can show different forms after heat treating regime processing.The mechanical property of laser 3D printing TC4 alloy depends on tissue The requirements of the national standard of forging is not achieved in state, the deposited components performance of TC4 alloy under normal circumstances, at heat Science and engineering skill changes its structural state, and then changes its service performance.

Heat treatment method traditional at present is the most important post-processing approach of titanium alloy 3D printing part, including solid solution aging heat Processing and annealing heat-treatment.It is prepared by the paper of entitled " influence of the fixation rates to laser 3D printing TC4 microstructure and property " Deposited TC4 alloy 3D printing part, it is 953Mpa that tensile strength, which is 1030MPa yield strength, elongation 7.0%, is discontented with Sufficient requirements of the national standard (σ b >=895MPa, 0.2 >=828MPa of σ, δ >=10%).Carrying out 950 DEG C/1h/WQ+540 DEG C/4h/AC After fixation rates, primary alpha phase length-width ratio is substantially reduced, and corynebacterium α phase is in the majority in tissue, forms apparent mesh basket tissue. The comprehensive mechanical property of printout is improved, and room temperature tensile intensity is 990MPa, yield strength 920MPa, elongation are 11.5%, reach forging national standard.Entitled " the Ti-6Al-4V alloy structure that heat treatment prepares electron beam selective melting With the influence of mechanical property " paper preparation TC4 alloy 3D printing part after the annealing of 850 DEG C/2h/AC, sample The microscopic structure of product changes smaller more as former state, and lamellar spacing has occurred a small amount of growth, and room temperature tensile intensity is 1000MPa, Yield strength is 953MPa, and elongation 10.6% reaches forging national standard.

Although heat treatment is able to ascend 3D printing part comprehensive performance, it is allowed to be able to satisfy the national standard of forging, it is traditional Heat treatment method that there are treatment effeciencies is extremely low, the processing time is long, can not carry out to part performance requirement different parts different The disadvantages of heat treatment, heat treatment parameter are unable to accurately control, and material internal and the surface rate of heat addition are uneven, therefore need a kind of new Titanium alloy 3D printing part post-processing approach solve these while so that titanium alloy 3D printing part is met forging national standard and ask Topic.

Summary of the invention

The technical problem to be solved by the present invention is beating 3D by Electric Pulse Treatment 3D printing part (especially titanium alloy) Print part meets forging national standard in a very short period of time, while solving problems existing for heat treatment technics.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, scheme are as follows: through 3D printing, obtain 3D printing part Afterwards, using Electric Pulse Treatment, finished product is obtained.

3D printing part described in a kind of method for using Electric Pulse Treatment 3D printing part of the present invention is titanium alloy 3D printing part；Institute Titanium alloy 3D printing part is stated to prepare by following step:

The preparation of step 1 titanium alloy powder,

Using titanium alloy as raw material, prepared sizes are 53-150 μm of spherical powder；

Step 2 titanium alloy 3D printing,

Using spherical powder obtained by step 1 as raw material, titanium alloy 3D printing part is prepared by 3D printing.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, when the 3D printing part is titanium alloy 3D printing part When, the Electric Pulse Treatment parameter of use are as follows: current density 15-30A/mm², pulsewidth 76-83 μ s, pulse frequency 250-350Hz.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, when the 3D printing part is titanium alloy 3D printing part When, the Electric Pulse Treatment parameter of use are as follows: current density 16-21.5A/mm², pulsewidth 76-80 μ s, pulse frequency 250-300Hz.

Under conditions of guaranteeing that product has some strength, its elongation percentage is promoted as far as possible, following proposal can be used: working as institute State 3D printing part be titanium alloy 3D printing part when, the Electric Pulse Treatment parameter of use are as follows: current density 21.4-21.5A/mm², arteries and veins Wide 80 μ s, pulse frequency 300Hz.

Under conditions of guaranteeing that product has certain elongation percentage, its intensity is promoted as far as possible, following proposal can be used: working as institute State 3D printing part be titanium alloy 3D printing part when, the Electric Pulse Treatment parameter of use are as follows: current density 16.6A/mm², 76 μ of pulsewidth S, pulse frequency 250Hz.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, during titanium alloy 3D printing, laser 3D is beaten Print selected parameter is laser power 2000-2200W, scanning speed 400-600mm/s, powder feed rate 3-7g/min, overlapping rate 49- 51%%, powder feeding gas (Ar) flow 13-17L/min, laser spot diameter 3-5mm and defocusing amount+(4-6) mm.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, the Electric Pulse Treatment process of titanium alloy 3D printing part In, Electric Pulse Treatment and soaking time are 10-30min, air-cooled processing after heat preservation.

Technique through the invention, can prepare that defect is few, and Tissue distribution is reasonable, and the high titanium alloy 3D of comprehensive performance is beaten Printed document.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention is right in step 1 titanium alloy powder preparation process Then the polishing of titanium alloy substrate surface is wiped using the oxidation film and greasy dirt of the method removal substrate surface of chemical cleaning with acetone Wash clean is put into vacuum oven drying (200 DEG C, 1h).Using plasma rotating electrode (rotation speed >=30000rpm) method The spherical powder of preparation, granularity are 53-150 μm.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, during step 2 titanium alloy 3D printing, titanium Alloy 3D printing part, is made by LMD equipment.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, it is lazy during step 2 titanium alloy 3D printing Property atmosphere Processing Room use 99.99%Ar protective gas, control the water oxygen content < 50ppm in cabin.

The principle of the invention are as follows: Electric Pulse Treatment be by high-duty heat based on (rate of heat addition is about 200~3000 DEG C/ S), electric pulse fuel factor act on so that 3D printing part (especially titanium alloy 3D printing part) be heated in a few seconds it is high Temperature can be effectively carried out the through heating of part, improve present in 3D printing part (especially titanium alloy 3D printing part) not The defects of fusion, cold shut defect, unmelted powder particle.

Its flow stress can be substantially reduced by applying pulse current to titanium alloy 3D printing part, and atom can be promoted to spread, and be drawn Stress relaxation is played, grain-boundary sliding is coordinated, inhibit the formation in inside parts cavity and is grown up, can be improved in titanium alloy 3D printing part Existing hole defect promotes the consistency of part.

A kind of method using Electric Pulse Treatment 3D printing part of the present invention, after definition process the porosity of 3D printing part be A, The porosity of 3D printing part is B before definition process, then [1- (B-A)/B] >=0.45.

Pulsed current annealing can make titanium alloy 3D printing part undergo phase transition or recrystallize in the solid state, lead to crystal grain refinement, To improve the fatigue life of part.And when being generally acknowledged that pulse current effect, pulse current transports persistent slip bands Dislocations Dislocation motion in dynamic or secondary slip system has an impact, and when the internal flaw phase separation of electronics and part, can be improved glide band Uniformity, increase the fatigue life of material, reduce the porosity of part.

Compared with prior art, present invention has the advantage that

1. treatment effeciency is high.Electric pulse carries out high-duty heating, and titanium alloy 3D printing part is heated to one in a few seconds Very high temperature, soaking time is in 10-30min, far below the time needed for fixation rates and annealing heat-treatment.

2. Local treatment can be carried out according to the performance requirement of part different parts.It controls at electric pulse parameter and electric pulse The region of reason applies the electric pulse of different parameters to part different zones, reaches the performance requirement of part.

3. Electric Pulse Treatment can be accurately controlled pulse frequency, pulsewidth, the processing parameters such as time and current density.

4. Electric Pulse Treatment can heat printout surface and inside simultaneously, it is evenly heated.

In conclusion a kind of method using Electric Pulse Treatment titanium alloy 3D printing part of the present invention, utilizes electric pulse pair The high-duty heat effect of material, " Electroplastic " effect and recrystallization improve titanium alloy 3D printing part in hole, The defects of hole, improves the comprehensive performance of titanium alloy 3D printing part.And compensate for some defects of prior heat treatment.

Specific embodiment