CN103350148B - The direct-cooled technique of cooling fluid based on the hot-forming die of boron steel steel pipe and device - Google Patents
The direct-cooled technique of cooling fluid based on the hot-forming die of boron steel steel pipe and device Download PDFInfo
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Abstract
A kind of direct-cooled technique of cooling fluid of the hot-forming die based on boron steel steel pipe of heat treatment plastic forming technology field and device, the method is: according to the geometric properties of product section to be formed, position corresponding in hot forming tool is divided into the salient angle region being arranged in patrix, concave domain and plane domain and be arranged in concave domain and the plane domain of counterdie, wherein: the profile in salient angle region is set to shape identical with finished product profile, and some the semi-open cooling fluid passages be interconnected are set on the surface of the plane domain of upper die and lower die and the cambered surface of concave domain respectively, then boron steel steel pipe be heated to austenitizing in heater and be placed in hot forming tool and form process by forcing press effect in the scope of 450 ~ 850 DEG C, in semi-open cooling fluid passage, input cooling fluid while finally keeping hot forming tool closed, make the coolant flow in semi-open cooling fluid passage and direct workpiece to be cooled.The present invention both can make workpiece be shaped smoothly by mould punching at shaping stage, can realize cooling fluid again directly cool workpiece at pressurize cooling stage.
Description
Technical field
What the present invention relates to is a kind of method and apparatus of heat treatment plastic forming technology field, specifically a kind of direct-cooled technique of cooling fluid of the hot-forming die based on boron steel steel pipe and device.
Background technology
Boron steel steel pipe is as a series of hot forming steel pipe, and production technology as shown in Figure 1, is divided into shaping and 2 stages of quench cooled, wherein: shaping stage needs at high temperature to be shaped by mould punching; The quench cooled stage needs by controlling certain cooling velocity, and the transformation from austenite microstructure to martensite microstructure can occur, obtain high intensity and hardness: be different according to boron steel kind, its intensity can reach 500 ~ 2000MPa.After common hot forming, intensity reaches the boron steel chemical composition of 1500MPa and is:
| C | Si | Mn | P | S | Cr | B | |
| min | 0.20 | 0.20 | 1.00 | - | - | 0.15 | 0.0015 |
| max | 0.25 | 0.35 | 1.30 | 0.025 | 0.015 | 0.25 | 0.0050 |
The die quenching type of cooling common at present arranges cooling water channel at mould inside.Namely the boron steel workpiece under high temperature, is entered pressurize cooling stage, first transfers heat to mould steel after being shaped by mould punching, and mould steel transfers heat to the cooling water channel be arranged in wherein again, thus realizes the cooling to boron steel workpiece; The cooling effectiveness of this mode workpiece, not only depends on the arrangement of cooling water channel, is limited to the heat transfer efficiency of mould steel simultaneously, belongs to the hot forming processing technology that cooling fluid cools workpiece indirectly.
Through finding the retrieval of prior art, Chinese patent literature CN102939221A, publication date 2013-02-20, disclose the manufacture method of a kind of bumper bottom reinforcing material, it comprises: cut off by specific length the cut-out step that hardenability element adds steel pipe; With the heat treatment step that forming temperature heats the steel pipe cut off; By utilizing extrusion die, the hot-forming hot-forming step being shaped to the shape of the horizontal part possessing planar portions in both sides is carried out to the steel pipe of above-mentioned heating; And the cooling step of cooling is fast carried out to shaping horizontal part under the state of closed above-mentioned extrusion die.But this technology enters pressurize cooling stage after being shaped by mould punching, first transfers heat to mould steel, mould steel transfers heat to the cooling fluid path be arranged in wherein again, thus realizes the cooling to boron steel workpiece; The cooling effectiveness of this mode workpiece, not only depends on the arrangement of cooling water channel, is limited to the heat transfer efficiency of mould steel simultaneously, belongs to the hot forming processing technology that cooling water cools workpiece indirectly.
Summary of the invention
The present invention is directed to prior art above shortcomings, a kind of direct-cooled technique of cooling fluid and device of the hot-forming die based on boron steel steel pipe are proposed, both by mould punching, workpiece can be shaped smoothly at shaping stage, and cooling fluid can be realized at pressurize cooling stage again and directly cool workpiece.
The present invention is achieved by the following technical solutions:
The present invention relates to a kind of direct-cooled technique of cooling fluid of the hot-forming die based on boron steel steel pipe, comprise the following steps:
The first step, according to the geometric properties of product section to be formed, position corresponding in hot forming tool is divided into the salient angle region being arranged in patrix, concave domain and plane domain and be arranged in concave domain and the plane domain of counterdie, wherein: the profile in salient angle region is set to shape identical with finished product profile, and some the semi-open cooling fluid passages be interconnected are set on the surface of the plane domain of upper die and lower die and the cambered surface of concave domain respectively, the head end of this semi-open cooling fluid passage and end are connected to form cooling liquid loop with the cooling liquid interface of hot forming tool respectively.
Second step, shaping stage: boron steel steel pipe is heated to after austenitizing in heater, be placed in hot forming tool and form process by forcing press effect in the scope of 450 ~ 850 DEG C.
The temperature of described austenitizing is 850 ~ 950 DEG C.
Described connection refers to: be arranged in part of the upper die and be communicated with respectively with the semi-open cooling fluid passage of part of the lower die and form one or several entrance and exit respectively, described entrance and exit is connected with entrance with the outlet of forcing press respectively.
3rd step, pressurize cooling stage: in semi-open cooling fluid passage, input cooling fluid while keeping hot forming tool closed, make the coolant flow in semi-open cooling fluid passage and directly to cool workpiece.
The cooling velocity of described cooling fluid to workpiece is more than or equal to 50 DEG C/sec, and cooling fluid initial temperature is between 5 ~ 45 DEG C.
The cambered surface of described concave domain arranges and refers to: according to the size of the arc radius of product section concave domain to be formed, to the biased 0 ~ L-3(mm in the direction that arc radius reduces) position semi-open cooling fluid passage is set, wherein: L is the arc length of concave domain.
The present invention relates to the device realizing above-mentioned technique, comprising: the cooling fluid feed system provided for mould with the patrix of salient angle region, concave domain and plane domain, the counterdie with concave domain and plane domain, some the semi-open cooling fluid passages being arranged at the cambered surface of concave domain and the surface of plane domain in upper die and lower die respectively and forcing press.
Described device preferably includes heater, work handling device and forcing press further, to realize further automated production.
Technique effect
Compared with prior art, advantage of the present invention comprises:
1) core of the present invention is: making full use of component shaping is this rule that mould salient angle is shaped, re-entrant angle does not play shaping effect, coolant channels is arranged at mould concave domain, neither affect the shaping of workpiece, can realize again cooling fluid to contact with the direct of workpiece, thus realization is shaped, cooling once completes.
2) component shaping and the direct Cooling Quenching of cooling fluid are integrated into a station realization by the present invention.In prior art, there is the technique using cooling water, oil, compressed air directly to cool boron steel steel pipe workpieces, but after component shaping, a station must be increased and be equipped with different operating modes, frock and equipment to realize beyond forming station.
3) cooling fluid directly cools workpiece, and cooling effectiveness is high.In prior art, have and use the mould steel of internal placement cooling fluid indirectly to cool workpiece, component shaping can be realized and Cooling Quenching completes at a station, but cooling fluid directly can not cool workpiece, heat is conducted by mould steel, the efficiency of cooling is not the efficiency of supply depending on cooling fluid usually, but depends on the heat transfer efficiency of mould steel.Use this technique, effectively can improve cooling effectiveness.
Hollow area cools.Particularly for cast part, some region is for the needs of product, and inside is hollow (upper and lower punch-die is contactless), just cannot apply packing pressure between the indirect cooling technology punch-die of at this moment traditional mould steel, thus cannot effective cooling workpiece.Use technology of the present invention, contactless at punch-die, without under the hollow state of packing pressure, equally can be used for cooling fluid, effective cooling is carried out to workpiece.
4) the present invention's indirect cooling technology that can indirectly cool workpiece with existing mold steel with the use of.On a specific workpiece, several situation is difficult to realize Homogeneous cooling below:
I) product geometric properties is complicated, and indirect cooling water road is difficult to even arrangement, even occurs cooling dead angle;
Ii) product is laser assembly solder plate (Tailored Welded Blank), and tubing itself is formed by the plate with laser welding of two or more different-thickness, pipe crimping.Zones of different due to thickness different, the method cooling effectiveness of tradition cooling is indirectly difficult to accomplish consistent with other regions;
Iii) product is do not wait material slab (Tailored Rolled Blank), and tubing itself is rolled into the steel pipe of two or more different-thickness by special cold-rolling process.Zones of different due to thickness different, the method cooling effectiveness of tradition cooling is indirectly difficult to accomplish consistent with other regions;
In above situation, according to actual needs, zones of different can unrestricted choice cooling fluid directly to cool or cooling fluid directly cools and combines indirectly cooling, mutually supplements, reaches Homogeneous cooling, the object of simultaneously enhancing productivity.
Accompanying drawing explanation
Fig. 1 is existing hot forming techniques schematic diagram;
In figure: a is for adding post forming; B is by pressurize quench cooled.
Fig. 2 is mould structure sectional schematic diagram of the present invention;
In figure: patrix 1, salient angle region 2, the semi-open cooling fluid passage 3 being arranged at concave domain, the semi-open cooling fluid passage 4 being arranged at plane domain, counterdie 5, product workpiece 6, closed cooling fluid passage 7.
Fig. 3 is semi-open cooling fluid passage schematic diagram in embodiment.
Detailed description of the invention
Elaborate to embodiments of the invention below, the present embodiment is implemented under premised on technical solution of the present invention, give detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment.
Embodiment 1
As shown in Figure 2, the present embodiment comprises: patrix 1, counterdie 5 and be arranged at some the semi-open cooling fluid passages 3,4 on patrix 1 and counterdie 5 surface respectively.Semi-open cooling fluid road is unified is D6 semi-circular recesses, and groove center spacing is unified is 12mm.Forcing press is 400T thermoforming special pressure machine, and provide cooling fluid to be the cooling water that initial temperature controls at 15 ~ 20 DEG C, flow set is 120L/Min.
Workpiece is the thick boron steel steel pipe of 1.5mm, length 1000mm, and steel pipe caliber is D50mm, and corner fillet is R6, i.e. arc length 37.68mm.
As shown in Figure 2, in hot forming process, due to the existence in salient angle region 2, can ensure that workpiece is shaped according to product design; Pressurize cooling stage, series cooling fluid passage 3,4 supply cooling fluid of arrangement, directly cools workpiece; For optimizing cooling effect further, the closed cooling fluid passage 7 of traditional indirect cooling is set in the salient angle region 2 of patrix 1.
Above-mentioned building mortion carries out concrete heat treatment by following steps:
1, boron steel materials in the tube are got the raw materials ready
2, in heater, 900 DEG C are heated to by plate complete austenitizing
3, within 6 seconds, boron steel materials in the tube are placed in a mold
4, press initial openings height 800mm, and, shaping closed with the speed of 300mm/s
5, forcing press is kept closed, and maintains the pressure of 400T, injects cooling fluid with 120L/Min simultaneously, directly carries out cooling fast 7 seconds to workpiece, and obtaining the final intensity needed is the martensitic structure of 1500MPa.
Embodiment 2
As shown in Figure 2, the present embodiment comprises: patrix 1, counterdie 5 and be arranged at some the semi-open cooling fluid passages 3,4 on patrix 1 and counterdie 5 surface respectively.Semi-open cooling fluid road is unified is D6 semi-circular recesses structure, and flute pitch is unified is 12mm.Forcing press is 150T thermoforming special pressure machine, and provide cooling fluid to be the cooling water that initial temperature controls at 15 ~ 20 DEG C, flow set is 50L/Min.
Workpiece is the thick boron steel steel pipe of 1.5mm, length 300mm, and steel pipe caliber is D50mm, and corner fillet is R6, i.e. arc length 37.68mm.
As shown in Figure 2, for optimizing cooling effect further, the closed cooling fluid passage 7 of traditional indirect cooling is set in the salient angle region 2 of patrix 1.
As shown in Figure 3, cooling fluid path flow needed for satisfied calculating, semi-open cooling fluid passage can have different cross sections as required, both can be circular groove structure (Fig. 3 a), also can be inverted trapezoidal (Fig. 3 b) or rectangular recess (Fig. 3 c) structure, can also be circular arc and rectangle or trapezoidal combining structure (Fig. 3 d), do appropriateness adjustment according to the change of product, the needs of cooling, the convenience etc. of processing and manufacturing completely.
Above-mentioned building mortion carries out concrete heat treatment by following steps:
1, boron steel materials in the tube are got the raw materials ready
2, in heater, 900 DEG C are heated to by plate complete austenitizing
3, within 6 seconds, boron steel materials in the tube are placed in a mold
4, press initial openings height 600mm, and, shaping closed with the speed of 300mm/s
5, forcing press is kept closed, and maintains the pressure of 150T, injects cooling fluid with 50L/Min simultaneously, directly carries out cooling fast 7 seconds to workpiece, and obtaining the final intensity needed is the martensitic structure of 1500MPa.
Embodiment 3
As shown in Figure 2, the present embodiment comprises: patrix 1, counterdie 5 and be arranged at some the semi-open cooling fluid passages 3,4 on patrix 1 and counterdie 5 surface respectively.Semi-open cooling fluid road is unified for 3mm is wide, the dark rectangular recess of 9mm, and groove center spacing is unified is 12mm.Forcing press is 150T thermoforming special pressure machine, and provide cooling fluid to be the cooling water that initial temperature controls at 15 ~ 20 DEG C, flow set is 120L/Min.
Workpiece is the thick boron steel steel pipe of 2.5mm, length 1000mm, and steel pipe caliber is D50mm, and corner fillet is R6, i.e. arc length 37.68mm.
As shown in Figure 2, for optimizing cooling effect further, the closed cooling fluid passage 7 of traditional indirect cooling is set in the salient angle region 2 of patrix 1.
Above-mentioned building mortion carries out concrete heat treatment by following steps:
1, boron steel materials in the tube are got the raw materials ready
2, in heater, 900 DEG C are heated to by plate complete austenitizing
3, within 6 seconds, boron steel materials in the tube are placed in a mold
4, press initial openings height 600mm, and, shaping closed with the speed of 300mm/s
5, forcing press is kept closed, and maintains the pressure of 400T, injects cooling fluid with 120L/Min simultaneously, directly carries out cooling fast 5 seconds to workpiece, and obtaining the final intensity needed is the martensitic structure of 1500MPa.
Claims (2)
1., based on the direct-cooled technique of cooling fluid of the hot-forming die of boron steel steel pipe, it is characterized in that, comprise the following steps:
The first step, according to the geometric properties of product section to be formed, position corresponding in hot-forming die is divided into the salient angle region being arranged in patrix, concave domain and plane domain and be arranged in concave domain and the plane domain of counterdie, wherein: the profile in salient angle region is set to shape identical with finished product profile, and some the semi-open cooling fluid passages be interconnected are set on the surface of the plane domain of upper die and lower die and the cambered surface of concave domain respectively, the head end of this semi-open cooling fluid passage and end are connected to form cooling liquid loop with the cooling liquid interface of hot-forming die respectively,
Second step, shaping stage: boron steel steel pipe is heated to after austenitizing in heater, be placed in hot-forming die and form process by forcing press effect in the scope of 450 ~ 850 DEG C;
3rd step, pressurize cooling stage: in semi-open cooling fluid passage, input cooling fluid while keeping hot-forming die closed, make the coolant flow in semi-open cooling fluid passage and directly to cool workpiece;
The temperature of described austenitizing is 850 ~ 950 DEG C;
The cambered surface of described concave domain arranges and refers to: according to the size of the arc radius of product section concave domain to be formed, to the direction that arc radius reduces, the position of biased 0 ~ (L-3) mm arranges semi-open cooling fluid passage, wherein: L is the arc length of concave domain;
Described connection refers to: be arranged in part of the upper die and be communicated with respectively with the semi-open cooling fluid passage of part of the lower die and form one or several entrance and exit respectively, described entrance and exit is connected with entrance with the outlet of forcing press respectively;
The cooling velocity of described cooling fluid to workpiece is more than or equal to 50 DEG C/sec, and cooling fluid initial temperature is between 5 ~ 45 DEG C.
2. one kind realizes the device of technique described in claim 1, it is characterized in that, comprising: the cooling fluid feed system provided for mould with the patrix of salient angle region, concave domain and plane domain, the counterdie with concave domain and plane domain, some the semi-open cooling fluid passages being arranged at the cambered surface of concave domain and the surface of plane domain in upper die and lower die respectively and forcing press;
Described patrix inside is provided with closes cooling fluid passage;
The cross section of described semi-open cooling fluid passage is circular groove structure, inverted trapezoidal groove structure, rectangular recess structure or its combination.
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| CN101508000A (en) * | 2009-03-24 | 2009-08-19 | 机械科学研究总院先进制造技术研究中心 | Novel super-high strength steel hot-forming die |
| CN101948943A (en) * | 2010-11-02 | 2011-01-19 | 湘电集团有限公司 | Mold surface quenching device and method |
| CN102039349A (en) * | 2009-10-23 | 2011-05-04 | 蒂森克虏伯金属成型技术有限公司 | Method and thermal recasting assembly for producing a hardened, thermally recast workpiece |
| CN102814403A (en) * | 2012-08-24 | 2012-12-12 | 天津职业技术师范大学 | High strength steel plate hot stamping die for automobile parts |
| CN102939221A (en) * | 2010-02-22 | 2013-02-20 | 现代Hysco株式会社 | Bumper lower stiffener with improved performance using ultra high strength steel pipe and manufacturing method thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP4664781B2 (en) * | 2005-09-12 | 2011-04-06 | 新日本製鐵株式会社 | Hot press molding die, hot press molding apparatus, and hot press molding method |
| KR100842710B1 (en) * | 2007-03-13 | 2008-07-01 | 학교법인 선목학원 | Oil cooling die which has function of preventing heat deformation and manufacturing method for machine parts using the same |
| KR101032535B1 (en) * | 2008-12-03 | 2011-05-04 | 주식회사 포스코 | Apparatus for hot press forming |
| WO2012160699A1 (en) * | 2011-05-26 | 2012-11-29 | トヨタ自動車株式会社 | Hot press device |
| WO2013001630A1 (en) * | 2011-06-29 | 2013-01-03 | トヨタ自動車株式会社 | Hot press device |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101508000A (en) * | 2009-03-24 | 2009-08-19 | 机械科学研究总院先进制造技术研究中心 | Novel super-high strength steel hot-forming die |
| CN102039349A (en) * | 2009-10-23 | 2011-05-04 | 蒂森克虏伯金属成型技术有限公司 | Method and thermal recasting assembly for producing a hardened, thermally recast workpiece |
| CN102939221A (en) * | 2010-02-22 | 2013-02-20 | 现代Hysco株式会社 | Bumper lower stiffener with improved performance using ultra high strength steel pipe and manufacturing method thereof |
| CN101948943A (en) * | 2010-11-02 | 2011-01-19 | 湘电集团有限公司 | Mold surface quenching device and method |
| CN102814403A (en) * | 2012-08-24 | 2012-12-12 | 天津职业技术师范大学 | High strength steel plate hot stamping die for automobile parts |
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