CN116237540A - Selective laser melting deformation and cracking prevention method - Google Patents
Selective laser melting deformation and cracking prevention method Download PDFInfo
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- CN116237540A CN116237540A CN202211733829.3A CN202211733829A CN116237540A CN 116237540 A CN116237540 A CN 116237540A CN 202211733829 A CN202211733829 A CN 202211733829A CN 116237540 A CN116237540 A CN 116237540A
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- selective laser
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- 238000002844 melting Methods 0.000 title claims abstract description 23
- 230000008018 melting Effects 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000005336 cracking Methods 0.000 title claims abstract description 14
- 230000002265 prevention Effects 0.000 title claims abstract description 6
- 239000000843 powder Substances 0.000 claims abstract description 20
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 15
- 239000000956 alloy Substances 0.000 claims abstract description 15
- 238000003466 welding Methods 0.000 claims abstract description 9
- 238000005516 engineering process Methods 0.000 claims abstract description 7
- 238000001931 thermography Methods 0.000 claims abstract description 7
- 230000005674 electromagnetic induction Effects 0.000 claims abstract description 6
- 238000012544 monitoring process Methods 0.000 claims abstract description 6
- 238000005457 optimization Methods 0.000 claims abstract description 5
- 238000004321 preservation Methods 0.000 claims abstract 2
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 239000003607 modifier Substances 0.000 claims description 6
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000013078 crystal Substances 0.000 claims 1
- 229910052751 metal Inorganic materials 0.000 abstract description 8
- 239000002184 metal Substances 0.000 abstract description 8
- 238000007711 solidification Methods 0.000 abstract description 8
- 230000008023 solidification Effects 0.000 abstract description 8
- 238000009826 distribution Methods 0.000 abstract description 6
- 238000005266 casting Methods 0.000 abstract description 5
- 230000007547 defect Effects 0.000 abstract description 4
- 238000002425 crystallisation Methods 0.000 abstract description 2
- 230000008025 crystallization Effects 0.000 abstract description 2
- 230000035882 stress Effects 0.000 description 5
- 230000004927 fusion Effects 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000010146 3D printing Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005137 deposition process Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 238000007514 turning Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/20—Direct sintering or melting
- B22F10/28—Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/30—Process control
- B22F10/36—Process control of energy beam parameters
- B22F10/362—Process control of energy beam parameters for preheating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/30—Process control
- B22F10/36—Process control of energy beam parameters
- B22F10/366—Scanning parameters, e.g. hatch distance or scanning strategy
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/30—Process control
- B22F10/36—Process control of energy beam parameters
- B22F10/368—Temperature or temperature gradient, e.g. temperature of the melt pool
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
- B22F10/50—Treatment of workpieces or articles during build-up, e.g. treatments applied to fused layers during build-up
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y30/00—Apparatus for additive manufacturing; Details thereof or accessories therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
- B33Y40/10—Pre-treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y70/00—Materials specially adapted for additive manufacturing
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Abstract
A selective laser melting deformation and cracking prevention method mainly comprises the following steps: 1) Preparing alloy powder containing an alterant and having good welding performance; 2) Electromagnetic induction type preheating and heat preservation; 3) Pool monitoring and laser beam scanning path optimization based on thermal imaging technology; 4) And (5) ultrasonic vibration grain refinement. Recent studies have shown that selective laser melt molded part cracking is related to deformation and residual stress distribution, which cracks are visible on specific metallographic longitudinal/transverse sections. Therefore, the invention starts from the alloy casting and welding defect mechanism and is based on the methods of powder melting, crystallization solidification and stress relief, and the method has important significance for preventing the deformation and cracking of the selective laser melting metal.
Description
Technical Field
The invention relates to a selective laser melting deformation and cracking prevention method, belonging to 3D printing process optimization and regulation technology.
Background
Additive manufacturing, due to its almost unlimited design freedom, facilitates the manufacture of geometrically complex parts that cannot be manufactured either by subtractive means (i.e. turning, milling or drilling) or by conventional casting, the most widely used metal additive manufacturing processes being those based on Directional Energy Deposition (DED) and Powder Bed Fusion (PBF), which are more suitable for the production of small and medium-sized parts with more complex geometry and higher precision than directional energy deposition processes because of their thinner layer thicknesses, smaller beam sizes, laser Powder Bed Fusion (LPBF) being said to be the most flexible powder bed fusion technique based on optical absorption of high energy beams, which is more easily adapted to new alloys, except for these beneficial effects, which are limited to small parts and small volume production due to low integration rates, recent studies have found that selective laser melt molded part cracking is related to the distribution of deformation and residual stresses, which cracks are visible on specific metallographic longitudinal/transverse sections, and that cracks generally can take into account phenomena known in conventional casting or welding to better understand the failure mechanism of metals with poor selective laser melt processability, in addition to cold cracking, certain metals such as stainless steel, aluminum-based and nickel-based alloys are also prone to cracking during solidification, which cracks are formed substantially by solidification shrinkage and thermal shrinkage during cooling, and furthermore, thermal stresses usually caused by the nature of the manufacturing process contribute to crack formation in semi-solid areas (also known as mushy zones), which types of cracks are known as hot cracks during casting, and hot cracks during welding, this phenomenon is called solidification cracking.
It has been found that different scanning patterns of selective laser melting can have a significant effect on the temperature field, which can affect the residual stress distribution and the geometric deformation of the component.
It has been found that the formation of cracks is related to temperature distribution, residual stress and poor fusion, the cracks formed by residual stress can be divided into solidification cracks and liquefaction cracks, the cracks are related to materials, the solidification cracks are caused by larger temperature gradient between a molten pool and solidified metal, so that the molten pool generates larger deformation, however, the fluidity of liquid is insufficient, and the deformation generated by the molten pool cannot be supplemented; liquified cracks occur in the partially melted region, which is related to liquification range, grain structure, thermal elongation, shrinkage and confinement of the metal, under-melted cracks occur more between adjacent scanned melt channels or between deposited layers, mainly due to incomplete melting of the metal powder, and delamination defects may also result when the cracks are severe.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method based on powder melting, crystallization solidification and stress relief starting from an alloy casting and welding defect mechanism, which has important significance for preventing deformation and cracking of selective laser melting metal.
In order to achieve the above purpose, the present invention provides the following technical solutions: a selective laser melting deformation and cracking prevention method mainly comprises the following steps.
Step 1: preparation of a selective laser melting powder.
Step 2: an electromagnetic induction type preheating heat-preserving temperature-controlling device.
Step 3: bath monitoring and laser beam scanning path planning based on thermal imaging techniques.
Step 4: an ultrasonic vibration device.
Drawings
FIG. 1 is a flow chart of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described in conjunction with the flowcharts of the present invention, and it is apparent that the described embodiments are only some embodiments of the invention, but not all embodiments, and all other embodiments obtained by persons skilled in the art without making creative efforts based on the embodiments of the present invention are all within the scope of protection of the present invention.
The first embodiment is as follows: the following steps specifically illustrate the selective laser melting deformation-resistant cracking process.
Preparation of selective laser melting powder: preparing alloy with good welding performance into selective laser melting powder, and adding refined grain modifier into the traditional selective laser melting powder for mixing.
Ensuring good welding performance of the alloy and being added with an modifier to be beneficial to balance the distribution of alloy crystalline phases in the solidification process of a molten pool.
In order to reduce splashing during laser scanning, electromagnetic induction heating and laser beam preheating are performed on the selective laser melting powder.
The temperature distribution of the laser melting area is formed by a thermal imaging technology, and the electromagnetic heater and the laser beam are regulated so that the heating temperature is close to but lower than the powder melting critical value and the powder melting and vaporization splashing are not caused.
In the process of selective laser melting, the laser scanning path of the part is optimized by monitoring the temperature of the molten pool.
By adopting a digital twinning method, the characteristics of the molten pool are reproduced in real time through temperature sensing, and then the laser scanning path of the part is optimized to obtain a more stable molten pool state.
After forming a molten pool by laser scanning, carrying out refining of alloy grains by an auxiliary ultrasonic vibration method.
It will be obvious to a person skilled in the art that the present invention is not limited to details of the above-described exemplary embodiments, and that the present invention may be implemented in other forms of installation without departing from the spirit or essential characteristics thereof, and therefore that the embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (5)
1. A selective laser melting deformation and cracking prevention method mainly comprises the following steps: (a) Preparing alloy powder containing an alterant and having good welding performance; (b) electromagnetic induction type preheating and heat preservation; (c) Pool monitoring and laser beam scanning path optimization based on thermal imaging technology; (d) ultrasonic vibration grain refinement.
2. The method according to claim 1, wherein the method for producing (a) the alloy powder with good weldability containing the modifier is specifically: by adjusting the content proportion of the alloy powder and the proportion of the modifier, the powder has better welding performance, and the alloy powder containing the modifier is directly prepared or the alloy powder and the modifier powder are respectively prepared and mixed according to a proper proportion.
3. The electromagnetic induction type preheating and heat preserving device according to claim 1, wherein the electromagnetic induction type preheating and heat preserving device is characterized in that: before laser processing, the powder in the processing area is preheated by being matched with laser beam heating.
4. The (c) thermal imaging technology based bath monitoring and laser beam scanning path optimization according to claim 1, characterized in that the (c) thermal imaging technology based bath monitoring and laser beam scanning path optimization is specifically: the characteristics of the molten pool are reproduced in real time by a digital twin method by using a thermal imaging technology, and then the scanning path of laser is dynamically adjusted, so that the molten pool is in a more stable state.
5. The ultrasonic vibration grain refinement of claim 1 (d), in which the ultrasonic vibration grain refinement of (d) is specifically: after selective laser melting to form molten pool, ultrasonic vibration is applied to refine alloy crystal grains.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211733829.3A CN116237540A (en) | 2022-12-31 | 2022-12-31 | Selective laser melting deformation and cracking prevention method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211733829.3A CN116237540A (en) | 2022-12-31 | 2022-12-31 | Selective laser melting deformation and cracking prevention method |
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| Publication Number | Publication Date |
|---|---|
| CN116237540A true CN116237540A (en) | 2023-06-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211733829.3A Pending CN116237540A (en) | 2022-12-31 | 2022-12-31 | Selective laser melting deformation and cracking prevention method |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1737197A (en) * | 2005-09-01 | 2006-02-22 | 上海交通大学 | Crack controlling means for laser deposition formed metal parts |
| US20130112042A1 (en) * | 2011-11-04 | 2013-05-09 | GM Global Technology Operations LLC | Apparatus and method for degassing cast aluminum alloys |
| CN105798294A (en) * | 2014-12-30 | 2016-07-27 | 哈尔滨润德伟业科技发展有限公司 | Rapid part prototyping method for refractory materials |
| CN106626378A (en) * | 2016-11-25 | 2017-05-10 | 西安交通大学 | Dynamic adjustment method for process parameters in selective laser sintering sub regions |
| CN107116217A (en) * | 2017-04-27 | 2017-09-01 | 哈尔滨理工大学 | Selective laser melting forming process, which prepares TiC, strengthens the method for nickel-base composite material |
| CN107442774A (en) * | 2017-07-26 | 2017-12-08 | 西安交通大学 | The method that sensing heating aids in alterant refining laser increasing material manufacturing titanium alloy crystal grain |
| CN112570732A (en) * | 2020-12-23 | 2021-03-30 | 湖南大学 | Method for reducing hot cracking sensitivity of laser additive manufacturing nickel-based high-temperature alloy |
-
2022
- 2022-12-31 CN CN202211733829.3A patent/CN116237540A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1737197A (en) * | 2005-09-01 | 2006-02-22 | 上海交通大学 | Crack controlling means for laser deposition formed metal parts |
| US20130112042A1 (en) * | 2011-11-04 | 2013-05-09 | GM Global Technology Operations LLC | Apparatus and method for degassing cast aluminum alloys |
| CN105798294A (en) * | 2014-12-30 | 2016-07-27 | 哈尔滨润德伟业科技发展有限公司 | Rapid part prototyping method for refractory materials |
| CN106626378A (en) * | 2016-11-25 | 2017-05-10 | 西安交通大学 | Dynamic adjustment method for process parameters in selective laser sintering sub regions |
| CN107116217A (en) * | 2017-04-27 | 2017-09-01 | 哈尔滨理工大学 | Selective laser melting forming process, which prepares TiC, strengthens the method for nickel-base composite material |
| CN107442774A (en) * | 2017-07-26 | 2017-12-08 | 西安交通大学 | The method that sensing heating aids in alterant refining laser increasing material manufacturing titanium alloy crystal grain |
| CN112570732A (en) * | 2020-12-23 | 2021-03-30 | 湖南大学 | Method for reducing hot cracking sensitivity of laser additive manufacturing nickel-based high-temperature alloy |
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