CN103418788A - Device and method for thermoforming gradient materials - Google Patents
Device and method for thermoforming gradient materials Download PDFInfo
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- CN103418788A CN103418788A CN2013103094025A CN201310309402A CN103418788A CN 103418788 A CN103418788 A CN 103418788A CN 2013103094025 A CN2013103094025 A CN 2013103094025A CN 201310309402 A CN201310309402 A CN 201310309402A CN 103418788 A CN103418788 A CN 103418788A
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Abstract
The invention discloses a device and method for thermoforming gradient materials. An upper mold base and a lower mold base are connected through a supporting post. A lower ejector rod and the lower mold base form sliding fit through a guide post hole in the center of the lower mold base and a slope. The upper surface of the lower ejector rod and the upper surface of the lower mold base are located in a same plane. A plurality of molds which are same in structure are stacked up and down and installed into gradient mold molds, and the molds are fixed on the lower mold base. Every two adjacent molds are isolated by asbestos gaskets respectively. The lower end of an upper punch and the center holes of the molds are coaxially installed to form sliding fit. The lower end of an upper mold connecting rod stretches into the position between the upper mold base and the lower mold base and is connected with the upper end of the upper mold punch. The upper end of the upper mold connecting rod stretches out of the upper mold base. By the adoption of the mode that the molds are installed in a gradient mode, so that powder materials which need to be located in different temperature intervals can be heated in the gradient mode; stable axial temperature gradients can be generated by heating rods and thermocouples, wherein the heating rods and the thermocouples are evenly distributed. By the adoption of the lower ejector rod, demolding can be rapidly conducted, and therefore production efficiency is improved.
Description
Technical field
The present invention relates to the device and method of shaping of metal powders, especially relate to a kind of device for the functionally gradient material (FGM) hot forming and manufacturing process with automatic demoulding functions.
Background technology
Powder metallurgy be produce metal or with metal dust (or mixture of metal dust and non-metal powder) as raw material, through being shaped and sintering, manufacture the technology of metal material, composite and all kinds goods.That PM technique possesses is significantly energy-conservation, economize material, excellent performance, Product Precision is high and the series of advantages such as good stability, is very suitable for producing in enormous quantities.
Gradient function composite (functionally graded materials), at first its concept by Japanese Xinye just proposing in 1986 with the quick male scholar of grade of horizontal well, it refers to that the Nomenclature Composition and Structure of Complexes of material changes to another orientation continuously from a certain orientation of material, makes the performance of material and a kind of novel functional material that function presents graded.
The composition of functionally gradient material (FGM) is graded, and the sintering temperature difference of each layer utilizes traditional sintering method to be difficult to once-firing.Utilize the methods such as chemical vapour deposition (CVD), physical vapour deposition (PVD) to prepare functionally gradient material (FGM), cost is very high, also is difficult to realize industrialization.Utilize the combination of discharge plasma sintering technique and graphite jig, at mould inner wall, produce the gradient temperature field, also can prepare functionally gradient material (FGM), but exist discharge plasma sintering furnace apparatus high cost and graphite jig to have the problems such as intensity is low, repeat usage is low.
Chinese invention patent (application number 200510094154.2) discloses a kind of method and apparatus of preparing gradient material by laser impacting welding.This device consists of laser generator, light-conducting system, absorbed layer material and workpiece clamp system, utilizes laser blast wave as the power source of impacting welding forming, utilizes the controllability of laser parameter to realize that precision welding is shaped.This device can accurately be controlled the intensity of weld interface and in conjunction with the degree of depth, but unavoidably can produce larger welding stress and welding gap at contact layer.
Chinese utility model patent (application number 201120380426.6) discloses a kind of graphite jig for sintering gradient material, comprises die, liner, punch seaming chuck, punch push-down head, thermocouple and powder to be sintered.When this mould utilizes discharge plasma sintering, partly there will be the density skewness of electric current at the frustum of a cone of die due to electric current, the closeer part of electric current can produce more Joule heat, thereby produces axial-temperature gradient in the frustum of a cone part of die.Utilize this mould can produce stable axial-temperature gradient, and powder inner radial thermograde to be sintered is little, sintering pressure is large, and mould is not easy to damage.But because frustum of a cone gradient is fixed, so the thermograde of mould inner wall temperature is non-adjustable and thermograde is limited.
Summary of the invention
The object of the present invention is to provide a kind of device for the functionally gradient material (FGM) hot forming and manufacturing process, have simple in structure, thermograde is controlled, it is seamless between moulding material to make, be shaped fast and the characteristics of automatic demoulding.
The technical solution used in the present invention is:
One, a kind of device for the functionally gradient material (FGM) hot forming:
Top mold frame of the present invention is connected by four pillars with lower mold holder; Lower mold holder is fixed by screw and base; The guide pillar hole of lower push rod by center on lower mold holder and inclined-plane and lower mold holder form and are slidably matched, and the upper surface of lower push rod and lower mold holder upper surface remain on same level; The mould that a plurality of structures are identical is installed by the mode of stack up and down, becomes the gradient mould, and is fixed on lower mold holder with long spiro nail, between adjacent molds, with asbestos washer, is isolated respectively; Upper punch lower end and a plurality of mold center hole are coaxially installed to form and are slidably matched, and the lower end of patrix connecting rod is stretched between top mold frame and lower mold holder, and is connected with the upper punch upper end, and stretch out outside top mold frame the upper end of patrix connecting rod.
The identical mould of described a plurality of structure, have the circular disk of circular hole all, it is trapezoidal boss that the circular disk upper surface has cross section, it is trapezoidal groove that the circular disk lower surface has cross section, boss and groove are coaxially arranged, are evenly equipped with two above heating rods and a detection thermocouple in the circumferential hole of circular disk; First asbestos washer pad is at the groove end face, and second, the 3rd asbestos washer pads respectively at the circular disk lower surface.
Two, a kind of method for the functionally gradient material (FGM) hot forming, the step of the method is as follows:
Pack in the die cavity of gradient mould a kind of powder to be sintered of material of step 1);
Step 2) it is descending that the patrix connecting rod drives upper punch, and a kind of powder to be sintered of material is carried out to compacting under normal temperature, and by the control to the powder amount, the height after powder is compacted is concordant with the top edge of bottom mould;
Pack on the powder of a kind of material the be compacted powder to be sintered of another kind of material of step 3), drive by the patrix connecting rod that upper punch is descending carries out compacting under normal temperature, by the control to the powder amount, powder is compacted rear concordant with the top edge of respective layer mould;
Step 4) repeats above-mentioned step, completes compacting under the normal temperature of all powders to be sintered;
Step 5) utilizes heating rod to be heated the gradient mould, forms the thermograde of die cavity inside, and corresponding material is carried out to gradient-heated, utilizes the pressure of upper punch to carry out hot pressing to the powder in forming process simultaneously, and pressurize a period of time;
Step 6), after powder forming completes, utilizes lower push rod that the shaping block is upwards ejected, and completes the demoulding.
The invention has the beneficial effects as follows:
(1) the described device for the functionally gradient material (FGM) hot forming, utilize uniform heating rod and thermocouple, can produce stable axial-temperature gradient; There is the function of different materials being carried out to gradient-heated, can effectively prepare FGM.
(2) the described method for the functionally gradient material (FGM) hot forming, can adopt the mode of precompressed to make the densification of multistage material, avoids occurring the gap of multistage material junction.
(3) the described device for the functionally gradient material (FGM) hot forming, equipment is simple, and replaceable parts has the characteristics such as automatic demoulding functions.
(4) adopt the underneath type push rod, can fast demoulding, improved production efficiency.
The accompanying drawing explanation
Fig. 1 is assembly structure schematic diagram of the present invention.
Fig. 2 is mould top view of the present invention.
Fig. 3 is die cut view of the present invention.
Fig. 4 is the process chart that the present invention adds a kind of material.
Fig. 5 is the process chart of a kind of material of precompressed of the present invention.
Fig. 6 is the process chart of two kinds of materials of precompressed of the present invention.
Fig. 7 is the process chart of two kinds of material releases of the present invention.
In figure: 1. lower mold holder, 2. screw, 3. pillar, 4. top mold frame, 5. nut, 6. lower push rod, 7. upper punch, 8. screw, 9. guide pin bushing, 10. patrix connecting rod, 11. long spiro nails, 12. moulds, 13. asbestos washer, 14. heating rods, 15. thermocouples, 16. 1 kinds of materials, 17. another kind of materials.
The specific embodiment
Below in conjunction with drawings and Examples, the present invention will be further described.
As shown in Figure 1, top mold frame 4 of the present invention is connected by four pillars, 3 use nuts 5 with lower mold holder 1; Lower mold holder 1 is fixed by screw 2 and base; The guide pillar hole of lower push rod 6 by center on lower mold holder 1 and inclined-plane and lower mold holder 1 form and are slidably matched, and the upper surface of lower push rod 6 and lower mold holder 1 upper surface remain on same level; The mould 12 that a plurality of structures are identical is installed by the mode of stack up and down, becomes the gradient mould, and is fixed on lower mold holder 1 with long spiro nail 11, between adjacent molds 12, with asbestos washer 13, is isolated respectively; Upper punch 7 lower ends and a plurality of mould 12 centre bores are coaxially installed to form and are slidably matched, 1 of top mold frame 4 and lower mold holder is stretched in the lower end of patrix connecting rod 10, and be connected with upper punch 7 upper ends by screw 8, stretch out outside top mold frame 4 upper end of patrix connecting rod 10, and patrix connecting rod 10 and top mold frame 4 coordinate by guide pin bushing 9.
As shown in Figure 2 and Figure 3, the mould 12 that a plurality of structures are identical, have the circular disk of circular hole all, it is trapezoidal boss that the circular disk upper surface has cross section, it is trapezoidal groove that the circular disk lower surface has cross section, boss and groove are coaxially arranged, are evenly equipped with two above heating rods 14 and a thermocouple 15 for detection in the circumferential hole of circular disk, can accurately control mould 12 temperature; First asbestos washer pad is at the groove end face, and second, the 3rd asbestos washer pads respectively at the circular disk lower surface.When adjacent molds 12 gradients are installed, on it, the inclined surface of the inclined surface of low groove and boss is outside direct contact portion, and asbestos washer is all arranged between remaining surface, to guarantee the installation accuracy of 12 of adjacent molds.
The described device of use that the present invention proposes carries out the method for functionally gradient material (FGM) hot forming, and its specific implementation process is as follows:
(1) pack in the die cavity of gradient mould a kind of powder to be sintered of material 16 as shown in Figure 4.
(2) as shown in Figure 5, it is descending that patrix connecting rod 10 drives upper punch 7, a kind of powder to be sintered of material 16 is carried out to compacting under normal temperature, by the control to the powder amount, height after powder is compacted is concordant with the top edge of bottom mould 12, in order to make commaterial in same temperature range.
(3) as shown in Figure 6, pack on the powder of a kind of material 16 the be compacted powder to be sintered of another kind of material 17, drive by patrix connecting rod 10 that upper punch 7 are descending carries out compacting under normal temperature, by the control to the powder amount, it is concordant with the top edge of respective layer mould 12 after powder is compacted, by this step, make all material all with corresponding mould 12 in sustained height.
(4) repeat above-mentioned step, complete compacting under the normal temperature of all powders to be sintered, by this step, both guaranteed functionally gradient material (FGM) and unification on corresponding mould 12 height, also eliminated functionally gradient material (FGM) gap between layers.
(5) as shown in Figure 6, utilize 14 pairs of moulds 12 of heating rod to be heated, the heating rod 14 of different layers needs to produce different heating powers by being shaped, and forms the thermograde of die cavity inside, and corresponding material is carried out to gradient-heated.Detect each layer of temperature by thermocouple 15, be incubated when each layer all reaches predetermined temperature, utilize the descending drive upper punch 7 of patrix connecting rod 10, the precompressed sample is carried out to hot pressing, and pressurize a period of time.
(6) as shown in Figure 7, treat that heat-insulation pressure keeping finishes, powder forming completes, and closes heating system.Upper punch 7 rises to certain altitude to be stopped, and utilizes lower push rod 6 that the shaping block is upwards ejected, and completes the demoulding.
Repeat above-mentioned operation, can realize continuous processing.
The above-mentioned specific embodiment is used for the present invention that explains, rather than limits the invention, and in the protection domain of spirit of the present invention and claim, any modification and change that the present invention is made, all fall into protection scope of the present invention.
Claims (3)
1. the device for the functionally gradient material (FGM) hot forming, it is characterized in that: top mold frame (4) is connected by four pillars (3) with lower mold holder (1); Lower mold holder (1) is fixed by screw (2) and base; Lower push rod (6) is slidably matched with lower mold holder (1) formation by guide pillar hole and the inclined-plane at the upper center of lower mold holder (1), and the upper surface of lower push rod (6) and lower mold holder (1) upper surface remain on same level; The mould that a plurality of structures are identical (12) is installed by the mode of stack up and down, becomes the gradient mould, and it is upper to be fixed on lower mold holder (1) with long spiro nail (11), between adjacent molds, with asbestos washer, is isolated respectively; Upper punch (7) lower end and a plurality of mould (12) centre bore are coaxially installed to form and are slidably matched, the lower end of patrix connecting rod (10) is stretched between top mold frame (4) and lower mold holder (1), and be connected with upper punch (7) upper end, stretch out outside top mold frame (4) upper end of patrix connecting rod (10).
2. a kind of device for the functionally gradient material (FGM) hot forming according to claim 1, it is characterized in that: the mould (12) that described a plurality of structures are identical, have the circular disk of circular hole all, it is trapezoidal boss that the circular disk upper surface has cross section, it is trapezoidal groove that the circular disk lower surface has cross section, boss and groove are coaxially arranged, are evenly equipped with two above heating rods (14) and a thermocouple for detection (15) in the circumferential hole of circular disk; First asbestos washer pad is at the groove end face, and second, the 3rd asbestos washer pads respectively at the circular disk lower surface.
3. a kind of method for the functionally gradient material (FGM) hot forming of installing according to claim 1, is characterized in that, the step of the method is as follows:
Pack in the die cavity of gradient mould a kind of powder to be sintered of material of step 1);
Step 2) it is descending that the patrix connecting rod drives upper punch, and a kind of powder to be sintered of material is carried out to compacting under normal temperature, and by the control to the powder amount, the height after powder is compacted is concordant with the top edge of bottom mould;
Pack on the powder of a kind of material the be compacted powder to be sintered of another kind of material of step 3), drive by the patrix connecting rod that upper punch is descending carries out compacting under normal temperature, by the control to the powder amount, powder is compacted rear concordant with the top edge of respective layer mould;
Step 4) repeats above-mentioned step, completes compacting under the normal temperature of all powders to be sintered;
Step 5) utilizes heating rod to be heated the gradient mould, forms the thermograde of die cavity inside, and corresponding material is carried out to gradient-heated, utilizes the pressure of upper punch to carry out hot pressing to the powder in forming process simultaneously, and pressurize a period of time;
Step 6), after powder forming completes, utilizes lower push rod that the shaping block is upwards ejected, and completes the demoulding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310309402.5A CN103418788B (en) | 2013-07-23 | 2013-07-23 | Device and method for thermoforming gradient materials |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201310309402.5A CN103418788B (en) | 2013-07-23 | 2013-07-23 | Device and method for thermoforming gradient materials |
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| CN103418788A true CN103418788A (en) | 2013-12-04 |
| CN103418788B CN103418788B (en) | 2015-05-20 |
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| CN201310309402.5A Expired - Fee Related CN103418788B (en) | 2013-07-23 | 2013-07-23 | Device and method for thermoforming gradient materials |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104368809A (en) * | 2014-10-30 | 2015-02-25 | 太仓市锦立得粉末冶金有限公司 | Powder alloy pressing mold used for output shaft |
| CN105970013A (en) * | 2016-05-04 | 2016-09-28 | 上海大学 | High-throughput preparation device and method for high-silicon aluminum alloy structural gradient material used for packaging |
| TWI669175B (en) * | 2018-04-03 | 2019-08-21 | 大陸商鑫京瑞鎢鋼（廈門）有限公司 | A hard alloy screw nut mold having multi-layer gradient structure and thereof method |
| CN113276435A (en) * | 2021-05-31 | 2021-08-20 | 济南大学 | Carbon-fibre composite hot-pressing sintering equipment can be regulated and control to structural gradient |
| CN114986970A (en) * | 2022-05-07 | 2022-09-02 | 昆明理工大学 | High-flux powder pressing control system and high-flux powder pressing method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104368809A (en) * | 2014-10-30 | 2015-02-25 | 太仓市锦立得粉末冶金有限公司 | Powder alloy pressing mold used for output shaft |
| CN104368809B (en) * | 2014-10-30 | 2017-01-25 | 太仓市锦立得粉末冶金有限公司 | Powder alloy pressing mold used for output shaft |
| CN105970013A (en) * | 2016-05-04 | 2016-09-28 | 上海大学 | High-throughput preparation device and method for high-silicon aluminum alloy structural gradient material used for packaging |
| TWI669175B (en) * | 2018-04-03 | 2019-08-21 | 大陸商鑫京瑞鎢鋼（廈門）有限公司 | A hard alloy screw nut mold having multi-layer gradient structure and thereof method |
| CN113276435A (en) * | 2021-05-31 | 2021-08-20 | 济南大学 | Carbon-fibre composite hot-pressing sintering equipment can be regulated and control to structural gradient |
| CN114986970A (en) * | 2022-05-07 | 2022-09-02 | 昆明理工大学 | High-flux powder pressing control system and high-flux powder pressing method |
| CN114986970B (en) * | 2022-05-07 | 2023-08-11 | 昆明理工大学 | High-flux powder pressing control system and high-flux powder pressing method |
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