CN100362120C - Method for fast mfg. metal/high-molecular composite material parts - Google Patents
Method for fast mfg. metal/high-molecular composite material parts Download PDFInfo
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- CN100362120C CN100362120C CNB2005100194987A CN200510019498A CN100362120C CN 100362120 C CN100362120 C CN 100362120C CN B2005100194987 A CNB2005100194987 A CN B2005100194987A CN 200510019498 A CN200510019498 A CN 200510019498A CN 100362120 C CN100362120 C CN 100362120C
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Abstract
The present invention discloses a method for rapidly forming metal/polymer composite material components. Firstly, an indirect SLS forming method is adopted to prepare a metal/polymer composite material component blank. Secondly, the blank is degreased and sintered at high pressure to obtain a porous metal component work blank, and the porous metal component work blank is infiltrated; the infiltration comprises: epoxy resin and phenolic resin or modified organic silicon are mixed firstly according to the weight ratio of 1: 2 to 2: 1, methyl-tetrahydrophthalic anhydride is added into the mixture at 60 to 80 DEG C; the mixture is stirred uniformly, the temperature is increased to 90 to 110 DEG C, and products are used as penetrating fluid for standby. Thirdly, the component is also preheated to 90 to 110 DEG C and then is soaked into the penetrating fluid to be infiltrated, and after gas bubbles disappear basically, the component is taken out. Finally, the permeated component is put into a constant temperature cabinet of 140 to 180 DEG C to be solidified with heat preserved, and after being cooled, the component is taken out. The method of the present invention can enhance the mechanical properties and the heat resistance of components, so that the method not only saves the cost and shortens the making time of components, but also reduced technical processes.
Description
Technical field
The invention belongs to advanced manufacturing field, be specifically related to the quick forming method of metal/high-molecular composite material parts.
Background technology
At present, the classical production process of metal/high-molecular composite part mainly contains: squeeze casting method, vacuum-air pressure teeming practice, powder metallurgic method, diffusion bonding method, extrusion process, roll method etc.Wherein, squeeze casting method is earlier toughener to be made preform, put into fixed model and be preheated to certain temperature, pour into metal melt, formpiston is depressed and pressurizeed, the cooling back demoulding promptly obtains part rapidly, this method advantage is a wetting property of having improved metal melt, also eliminated simultaneously defectives such as pore, but to the requirement of equipment than higher, and complex process.Vacuum one air pressure teeming practice is that comparison is new and be considered to method preferably, this method is after toughener is made preform and put into die cavity, heating also vacuumizes, with air pressure metal melt is pressed into die cavity then, the cooling back demoulding rapidly, this method is owing to be to vacuumize earlier to add lower pressure again, so it is little to fibre-tendering, its mechanical property is better than extruding, but its technology is also very complicated, and is also high to equipment requirements.Powder metallurgic method is to spread the layer of metal powder on the long polymkeric substance of arranging, fiber and metal-powder replaced mutually cold pressing after overlapping, sinter molding then, the advantage of this method is that the manufacturing temperature is low, be suitable for multiple metallic matrix and combine with high molecular, shortcoming is that the damage of high molecular polymer segment is big, skewness, content is not high, complex process.The diffusion bonding method is that the toughener metal that infiltrates after surface treatment is made precursor wire; be stacked in vacuum condition (or protective atmosphere) with tinsel (or powder) again and a little less than hot pressing diffusion bonding moulding under the temperature of melting point metal; this method is little to fiber loss; the composite density height that makes; but production efficiency is low, the equipment requirements height.Extruding or rolling make polymkeric substance and stratiform matrix bond, and the advantage of this method makes surface reaction little, the orientation rule, and shortcoming makes the segment of easy damage polymkeric substance, and is also restricted to the kind of metallic matrix, the cost requirement height.In sum, the manufacture method of metal current/high-molecular composite material parts not only manufacturing process complexity, the height of creating conditions, production efficiency is low, cost requirement is high, and is difficult to control part precision and intensity.Therefore the manufacture method of conventional metals/high-molecular composite material parts has hindered its large-scale production and application widely.
At present, adopt indirect selective laser sintering (Selective Laser Sintering, SLS) Rapid Manufacturing Technology, at first produce and have lacunose metal parts shape base, behind degreasing and high temperature sintering, form the porous metal parts blank, what obtain is metal parts, uses under the high condition of temperature and requirement of strength.
Summary of the invention
The method for fast mfg that the purpose of this invention is to provide a kind of metal/high-molecular composite material parts, the part of this method manufacturing have the characteristics of intensity height and good heat resistance.
The quick forming method of a kind of metal/high-molecular composite material parts provided by the invention, its step comprises:
(1), adopt the selective laser sintering and moulding method to prepare metal/high-molecular composite material parts shape base;
(2), the shape base obtains the porous metal parts blank behind degreasing and high temperature sintering;
(3), to the processing of infiltrating of above-mentioned porous metal parts:
(3.1) be to mix in 1: 2 ~ 2: 1 by weight with Resins, epoxy and resol or modified organic silicon, in the time of 60 ℃ ~ 80 ℃, add methyl tetrahydrophthalic anhydride therein, the weight ratio of methyl tetrahydrophthalic anhydride and Resins, epoxy is (0.4 ~ 0.8): 1, stir, be warming up to 100 ℃, standby as penetrating fluid; Simultaneously above-mentioned part also is preheated to 100 ℃;
(3.2) with infiltrating in the above-mentioned part immersion penetrating fluid, when treating that bubble disappears substantially, part is taken out;
(4) part after will permeating is put into 140 ℃～180 ℃ thermostat container heat preservation solidification, and cooling gets final product then.
The present invention adopts indirect SLS forming technique to make the method for metal/high-molecular composite material parts on the basis of commercial SLS technology.Indirectly SLS is shaped---by choosing the refractory metal powdered material and low melting point polymeric powder material is made metal parts, promptly in metal-powder, add certain binding agent, (generally below 100W) melts low-melting binding agent with less laser power, unfused refractory metal powder forms crude green body around the powder bonded of fusing, crude green body porosity behind the sintering is bigger, intensity neither be very high, must just can become closely knit metal function spare through aftertreatment.The present invention adopts that to ooze the resin technological process simple, and cost is low, and the part manufacturing cycle is short, and what obtain is metal/high-molecular composite material parts, can directly use as functional part under the low condition of temperature and requirement of strength.
The present invention can make the various metal/high-molecular composite material parts of shape and structure complexity, and this part adopts traditional method to be difficult to maybe can't make.
Description of drawings
Fig. 1 is a schematic flow sheet of the present invention.
Fig. 2 is the infiltration method figure of sintered part.
Fig. 3 is the enhanced mechanism synoptic diagram.
Embodiment
The present invention is further detailed explanation below in conjunction with accompanying drawing and example.
As shown in Figure 1, the step of the inventive method is:
(1), adopt the selective laser sintering and moulding method to prepare metal/high-molecular composite material parts shape base;
(2), the shape base obtains the porous metal parts blank behind degreasing and high temperature sintering;
(3), with the high temperature-resistant polymer material to the processing of infiltrating of above-mentioned porous metal parts, strengthen the intensity of part with this.Save cost than carry out infiltration with metal like this, reduce technological process, save time.Concrete grammar is as follows:
(3.1) be to mix in 1: 2～2: 1 by weight with Resins, epoxy and resol or modified organic silicon, in the time of 60 ℃～80 ℃, add solidifying agent-methyl tetrahydrophthalic anhydride (MeTHPA) again, the weight ratio of solidifying agent and Resins, epoxy is (0.4～0.8): 1, stir, be warming up to 90 ℃～110 ℃ again, standby as penetrating fluid.The viscosity of solution reduces gradually in the temperature-rise period, and mobile the enhancing infiltrated metal shape base hole easily.And above-mentioned part also is preheated to 90 ℃～110 ℃.
(3.2) part is immersed in the above-mentioned penetrating fluid infiltrate.In steeping process, the blank surface has a large amount of bubbles to produce, and is to begin first generation from the upper end, and moves down gradually, when treating that number of bubbles is gradually reduced to zero, part is taken out.This moment, the Resins, epoxy of piece surface was infiltrated up to the metalwork the inside, and surface liquid fades away.For the part of complicated shape, be to obtain the better effect of infiltration, available hairbrush is at the surface brush Resins, epoxy of metalwork, and repeated multiple times is no longer infiltrated until the Resins, epoxy of piece surface, and it is moistening that the surface becomes, and can think that Resins, epoxy oozes full part substantially.
(4) part after will permeating is put into 140 ℃～180 ℃ thermostat container heat preservation solidification 2～6 hours, and cooling is taken out and got final product then.
Embodiment 1:
The present invention adopts epoxy powder and 300 order 316L powder of stainless steel to mix down evenly as raw material in certain proportioning (as 1:100), by the HRPS-III of Central China University of Science and Technology type selective laser sintering (SLS) formation system, parameter setting is: laser energy 15W; Sweep velocity 2000mm/s; Sintering spacing 0.1mm; Sintered layer thickness 0.1mm.The prototype blank that obtains to carrying out degreasing, then is warmed up to and carries out high temperature sintering under 1180 ℃ the temperature and handle under 400 ℃-600 ℃ temperature under the condition of reducing atmosphere, and cooling is taken out and obtained the porous metal parts blank.
Resins, epoxy and resol were mixed by 1: 2, under 60 ℃ temperature, add 50% methyl tetrahydrophthalic anhydride (MeTHPA), and it is stirred, be warming up to 90 ℃ then gradually as solidifying agent.Simultaneously porous metal parts (1) also are preheated to 90 ℃, the viscosity of solution reduces gradually in the temperature-rise period, and mobile the enhancing infiltrated shape base hole easily.As shown in Figure 2, steeping process can adopt part (1) to put into steeping fluid (2) gradually, allow steeping fluid (2) progressively finish from shape base bottom to vertical infiltration, in steeping process, blank (1) surface has a large amount of bubbles to produce, and be to begin first generation from the upper end, and move down gradually, when treating that number of bubbles is gradually reduced to zero, blank (1) is taken out, this moment, the resin impregnated on surface arrived metal parts blank (1) the inside, and surface liquid fades away, and uses the surface brush resin of hairbrush at blank (1) this moment again, repeated multiple times, resin until the surface no longer infiltrates, and it is moistening that the surface becomes, and can think that resin oozes full shape base substantially.To ooze good blank (1) at last and be placed in 160 ℃ of thermostat containers under the temperature heat preservation solidification 6 hours, cooling is taken out and is obtained metal/high-molecular composite material parts then.
As shown in Figure 3, sample behind the sintering has a lot of holes and cavity, and behind the infiltration resin hole and cavity all by completely filled, the effect that the resin (3) of filling mainly mainly has two aspects for the influence of sample mechanical property: the one, cohesive action, further strengthen the contact of (4) between metallic particles, improved resistance to tension (5); The one, the hole between filling metallic particles for overlay makes to become more substantial between hole, thereby has hindered the particulate motion, increases barrier force (6), thereby has strengthened the mechanical property of sample.
Embodiment 2:
The present invention adopts epoxy powder and 350 order 420L powder of stainless steel to mix down evenly as raw material in certain proportioning (as 5:100), by the HRPS-III of Central China University of Science and Technology type selective laser sintering (SLS) formation system, parameter setting is: laser energy 15W; Sweep velocity 2000mm/s; Sintering spacing 0.1mm; Sintered layer thickness 0.1mm.The prototype blank that obtains to carrying out degreasing, then is warmed up to and carries out high temperature sintering under 1100 ℃ the temperature and handle under 400 ℃-600 ℃ temperature under the condition of reducing atmosphere, and cooling is taken out and obtained the porous metal parts blank.
Resins, epoxy and resol were mixed by 1: 1, under 60 ℃ temperature, add 50% methyl tetrahydrophthalic anhydride (MeTHPA), and it is stirred, be warming up to 100 ℃ then gradually as solidifying agent.Simultaneously porous metal parts (1) also are preheated to 100 ℃, the viscosity of solution reduces gradually in the temperature-rise period, and mobile the enhancing infiltrated shape base hole easily.As shown in Figure 2, steeping process can adopt part (1) to put into steeping fluid (2) gradually, allow steeping fluid (2) progressively finish from shape base bottom to vertical infiltration, in steeping process, blank (1) surface has a large amount of bubbles to produce, and be to begin first generation from the upper end, and move down gradually, when treating that number of bubbles is gradually reduced to zero, blank (1) is taken out, this moment, the resin impregnated on surface arrived metal parts blank (1) the inside, and surface liquid fades away, and uses the surface brush resin of hairbrush at blank (1) this moment again, repeated multiple times, resin until the surface no longer infiltrates, and it is moistening that the surface becomes, and can think that resin oozes full shape base substantially.To ooze good blank (1) at last and be placed in 160 ℃ of thermostat containers under the temperature heat preservation solidification 6 hours, cooling is taken out and is obtained metal/high-molecular composite material parts then.
As shown in Figure 3, sample behind the sintering has a lot of holes and cavity, and behind the infiltration resin hole and cavity all by completely filled, the effect that the resin (3) of filling mainly mainly has two aspects for the influence of sample mechanical property: the one, cohesive action, further strengthen the contact of (4) between metallic particles, improved resistance to tension (5); The one, the hole between filling metallic particles for overlay makes to become more substantial between hole, thereby has hindered the particulate motion, increases barrier force (6), thereby has strengthened the mechanical property of sample.
Embodiment 3:
The present invention adopts epoxy powder and 400 order 1Cr18Ni9Ti powder to mix down evenly as raw material in certain proportioning (as 1: 100), by the HRPS-III of Central China University of Science and Technology type selective laser sintering (SLS) formation system, parameter setting is: laser energy 15W; Sweep velocity 2000mm/s; Sintering spacing 0.1mm; Sintered layer thickness 0.1mm.The prototype blank that obtains to carrying out degreasing, then is warmed up to and carries out high temperature sintering under 1200 ℃ the temperature and handle under 400 ℃-600 ℃ temperature under the condition of reducing atmosphere, and cooling is taken out and obtained the porous metal parts blank.
Resins, epoxy and modified organic silicon were mixed by 2: 1, under 60 ℃ temperature, add 50% methyl tetrahydrophthalic anhydride (MeTHPA), and it is stirred, be warming up to 110 ℃ then gradually as solidifying agent.Simultaneously porous metal parts (1) also are preheated to 110 ℃, the viscosity of solution reduces gradually in the temperature-rise period, and mobile the enhancing infiltrated shape base hole easily.As shown in Figure 2, steeping process can adopt part (1) to put into steeping fluid (2) gradually, allow steeping fluid (2) progressively finish from shape base bottom to vertical infiltration, in steeping process, blank (1) surface has a large amount of bubbles to produce, and be to begin first generation from the upper end, and move down gradually, when treating that number of bubbles is gradually reduced to zero, blank (1) is taken out, this moment, the resin impregnated on surface arrived metal parts blank (1) the inside, and surface liquid fades away, and uses the surface brush resin of hairbrush at blank (1) this moment again, repeated multiple times, resin until the surface no longer infiltrates, and it is moistening that the surface becomes, and can think that resin oozes full shape base substantially.To ooze good blank (1) at last and be placed in 160 ℃ of thermostat containers under the temperature heat preservation solidification 6 hours, cooling is taken out and is obtained metal/high-molecular composite material parts then.
As shown in Figure 3, sample behind the sintering has a lot of holes and cavity, and behind the infiltration resin hole and cavity all by completely filled, the effect that the resin (3) of filling mainly mainly has two aspects for the influence of sample mechanical property: the one, cohesive action, further strengthen the contact of (4) between metallic particles, improved resistance to tension (5); The one, the hole between filling metallic particles for overlay makes to become more substantial between hole, thereby has hindered the particulate motion, increases barrier force (6), thereby has strengthened the mechanical property of sample.
Claims (1)
1. the quick forming method of a metal/high-molecular composite part, its step comprises:
(1), adopt the selective laser sintering and moulding method to prepare metal/high-molecular composite material parts shape base;
(2), the shape base forms the porous metal parts blank behind degreasing and high temperature sintering;
(3), to the processing of infiltrating of above-mentioned porous metal parts blank:
(3.1) be to mix in 1: 2～2: 1 by weight with Resins, epoxy and resol or modified organic silicon, in the time of 60 ℃～80 ℃, add methyl tetrahydrophthalic anhydride therein, the weight ratio of methyl tetrahydrophthalic anhydride and Resins, epoxy is (0.4～0.8): 1, stir, be warming up to 90 ℃～110 ℃, standby as penetrating fluid; Above-mentioned blank also is preheated to 90 ℃～110 ℃ simultaneously;
(3.2) with infiltrating in the above-mentioned blank immersion penetrating fluid, when treating that bubble disappears substantially, blank is taken out;
(4) blank after will permeating is put into 140 ℃～180 ℃ thermostat container heat preservation solidification, and cooling gets final product then.
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN100432025C (en) * | 2006-12-01 | 2008-11-12 | 华中科技大学 | Metal/ ceramic laser sintering product post-processing method |
| CN101767088B (en) * | 2009-12-11 | 2012-03-28 | 哈尔滨工业大学 | Method for enhancing interface properties of metal/epoxy resin composite material by using dendrimers |
| CN104647760B (en) * | 2015-02-12 | 2017-03-08 | 华中科技大学 | A kind of 3D printing manufacture method of short fiber reinforced thermosetting resin joint product |
| CN106739025B (en) * | 2016-11-23 | 2019-01-04 | 武汉理工大学 | The post-processing approach of 3D printing proton exchange film fuel cell electric piling inlet manifold |
| CN107650375A (en) * | 2017-09-22 | 2018-02-02 | 上海航天精密机械研究所 | Sintering Model resin impregnated method and mogullizer |
| DE102018208427B4 (en) * | 2018-05-28 | 2022-03-17 | Brembo Sgl Carbon Ceramic Brakes Gmbh | Process for manufacturing a component, the component itself and its use |
| CN113560578A (en) * | 2021-08-11 | 2021-10-29 | 苏州中耀科技有限公司 | Forming method of temporary metal mold |
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| US20050023710A1 (en) * | 1998-07-10 | 2005-02-03 | Dmitri Brodkin | Solid free-form fabrication methods for the production of dental restorations |
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| US20050023710A1 (en) * | 1998-07-10 | 2005-02-03 | Dmitri Brodkin | Solid free-form fabrication methods for the production of dental restorations |
| US6228437B1 (en) * | 1998-12-24 | 2001-05-08 | United Technologies Corporation | Method for modifying the properties of a freeform fabricated part |
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Assignee: Wuhan Binhu Mechanical & Electrical Co., Ltd. Assignor: Huazhong University of Science and Technology Contract fulfillment period: 2009.8.25 to 2016.8.25 contract change Contract record no.: 2009420010051 Denomination of invention: Method for fast mfg. metal/high-molecular composite material parts Granted publication date: 20080116 License type: Exclusive license Record date: 2009.9.8 |
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