The hot forming of high-duty steel part, punching and edge-cutting integrated technique and mould
Technical field
The present invention relates to hot press-formed and punching, trimming technology and the mould of high strength steel, AHSS and unimach punching parts, belong to the forming technique field of high strength steel sheet-metal parts.
Background technology
Current, at automobile manufacturing field, people have become the important pushing factor of technological progress to the demand of high security, low deadweight and good fuel economy.Manufacturers are achieved consumer's hope by introducing measures such as new security concept and light-weighted body structure.Especially aspect body structure,, improved the collision performance of automobile and also realized light-weighted requirement simultaneously by use to high strength steel, AHSS and unimach.But raising along with steel strength, percentage elongation descends, the forming property of material also reduces greatly, also be easy to generate in the forming process break, wrinkling, size is difficult to problems such as control and shape defect, traditional cold punching forming process can not satisfy the needs of technology and production development.
In recent years, Chinese scholars is developed a kind of new high strength, ultra-high strength steel hot stamping forming technology, this technology makes high strength steel and unimach plate be heated to austenitizing temperature (900~950 ℃) in heating furnace, and austenitic area maintenance 5 minutes, then plate is transferred to forcing press, in diel, carry out drawing and quenching simultaneously, make formation of parts obtain 100% martensitic structure.This technology can reduce the weight of automobile structure when improving collision performance and fatigue strength.
Chinese patent literature CN101288889 discloses a kind of " ultra-high strength steel hot stamping forming die ", this mould comprises upper bolster and is fixed on punch, the die shoe on the upper bolster and is fixed on die on the die shoe, be provided with cooling-water duct in the die, cooling-water duct is connected with a cooling water recirculation system.
Chinese patent literature CN1829813 discloses a kind of " method for hot forming and hot formed member ", for the steel plate of special component be heated to austenite point temperature (Ac3) above and keep after, carry out the shaping of end article shape, in the cooling of the forming temperature in shaping or after be shaped, the cooling velocity of the Ma Shi point temperature (Ms point) of arrival formed parts is more than critical cooling rate, and, be that Quenching Treatment is carried out in 25~150 ℃/s cooling with average cooling rate from Ms o'clock to 200 ℃.
There are through hole or hot forming part to have under the situation of binder flange on, the hot forming part higher, must carry out secondary operations the hot forming part for dimension precision requirement.In the cold stamping operation, generally be to utilize diel to carry out secondary operations such as punching, deburring, but in the drop stamping operation, utilize conventional mould structure to carry out very difficulty of secondary operations; The molded component that adopts cold punching die that the back intensity of quenching is improved is cut edge or punching processing needs very big processing load, metal pattern will be damaged or the lost of life, for the hot forming part of ultrahigh-strength steel plates even can't process with cold punching die.
In order to make hot formed high strength part meet corresponding dimensional accuracy and shape need, all adopt five laser cutting techniques to carry out punching and deburring at present, but laser is cut edge or to cut hole efficient low, article one, drop stamping generates line often needs the laser side cut of number cover or cuts the hole line supporting with it, in addition, every cover laser cut edge or cut the hole line all need corresponding anchor clamps to part position, clamping, thereby occupation area of equipment is big, equipment investment is many, production cost is high.In addition, after laser was cut edge or cut the hole, the side cut of hot forming part or Kong Bianhui had some motlten metals and solidify the formed metallic particles in back, need follow-up polishing operation that scrap metal is removed, cause the production cycle of hot forming part long, limited applying of drop stamping technology.When using the laser side cut or cutting the hole, the deadline is subjected to part dimension and hole count quantitative limitation, and the simplest part is fixed to the side cut anchor clamps from part and finishes and need may need a few minutes for complex parts more than 30 seconds to cutting.
Chinese patent literature CN2617549 discloses a kind of " novel hot piercing, shaving die ", the hot piercing, the shaving die that are used for forging, the disclosed mould of this patent can only utilize the slide block movement of forcing press, finish single punching, side cut, and it is compound to be used for shaping, side cut or punching, and in addition, this mould structure is to be used for bloom to forge, belong to the bulk forming field, can not be used to belong to the punching or the side cut of the high strength plate in sheet forming field.
Chinese patent literature CN101326022 discloses a kind of " multipart punch that is used for hydro piercing ", is used for forming the hole at the member of hydraulic expanding-forming.This multipart punch is after the part hydraulic expanding-forming is finished, and allows drift fall back on mould inside, utilizes highly pressurised liquid as power, will need the punching position to be cut into several, thereby finish punch process.This technology and structure only are applicable to the low-intensity steel plate of hydraulic expanding-forming, can not be used for the shaping and the punching of high-duty steel part.
Summary of the invention
The problem that used secondary operations technology exists when the present invention is directed to present high strength or unimach drawing part hot forming and side cut, punching, provide a kind of simple in structure, production efficiency is high, the hot forming of the measured high-duty steel part of matter, punching and edge-cutting integrated technique, and a kind of mould of realizing this technology is provided simultaneously.
The hot forming of high-duty steel part of the present invention, punching and edge-cutting integrated technique are:
At first on the hot-forming die of high-duty steel part, be provided with and cut edge and punching tool, before the high strength steel plate is hot press-formed, the high strength steel plate that is heated to after the complete austenitizing is positioned over punching press in the hot-forming die, after the hot-forming die closure, workpiece after then utilizing side cut on the hot-forming die and punching tool to punching press is cut edge and punch operation, after finishing hot-forming die is cooled off, utilize with the contacted mold component of formation of parts formation of parts is quenched.
Hot forming, punching and the edge-cutting integrated mould of realizing the high-duty steel part of above-mentioned integral process be by the following technical solutions:
This integrated mould comprises forming terrace die, shaping die, last punching tool, following punching tool, goes up side cut instrument and following side cut instrument, be provided with cooling-water duct in forming terrace die and the shaping die, the bottom exterior contour of forming terrace die is consistent with the profile of part, and the inner chamber profile of shaping die is consistent with the outer shape of part; Holding pad is housed on the forming terrace die, be provided with in the forming terrace die with part and want the corresponding through hole of punching position, in this through hole push rod is housed, the upper end of forming terrace die is equipped with the punching oil cylinder, the piston rod of last punching oil cylinder stretches in the through hole of forming terrace die and with the upper end of push rod and is connected, the lower end of push rod is connected with last punching tool, and the side cut oil cylinder is installed on the end face of holding pad, and the piston rod of last side cut oil cylinder and last side cut instrument link together; Also be provided with through hole in the shaping die, the through hole of this through hole and forming terrace die is on same axis; The lower end of shaping die is equipped with down side cut oil cylinder and following punching oil cylinder, the piston rod of following punching oil cylinder stretches in the through hole of shaping die and with following punching tool and is connected, the piston rod of following side cut oil cylinder is connected with a push rod, and this push rod links together with following side cut instrument.
Last side cut instrument and following side cut instrument carry out piecemeal according to the outer shape of part, and the piecemeal quantity of last side cut instrument and following side cut instrument is identical.
The thickness of last side cut instrument and following side cut instrument is 1.5~4.0 times of institute's processing parts wall thickness.
The present invention is after hot press-formed, before formation of parts being carried out in the mould quenching, utilization is disobeyed the side cut and the punching tool of the mould inside of depended on pressure function the hot forming part is cut edge and punching, after side cut and punching, again part is carried out quenching in the mould, this technology reduced hot formed equipment investment, reduced the floor space of equipment, reduced the hot forming part production cost, shortened production cycle of hot forming part, and the side cut of hot forming part and punching quality height, the dimensional accuracy of part and form accuracy height.Use side cut of the present invention and punching technology, the time of finishing side cut and punching technology is 1~2 second, and is not subjected to the restriction of part dimension and shape.
Description of drawings
Fig. 1 a is a kind of structural representation that needs the part of hot forming, punching, the compound one processing of side cut.
Fig. 1 b is the cutaway view of Fig. 1 a.
Fig. 2 is the structural representation (state before the edge-cutting and hole-punching dissects along the A-A cutting line among Fig. 3) of a kind of hot forming that is used for part shown in Figure 1, side cut, punching hole composite die tool.
Fig. 3 is the vertical view of Fig. 2.
Fig. 4 is the left view (state before the edge-cutting and hole-punching dissects along the center of side cut instrument) of Fig. 2.
Fig. 5 is the view behind the edge-cutting and hole-punching of hot forming shown in Figure 2, side cut and punching hole composite die tool.
Fig. 6 is the view behind the edge-cutting and hole-punching of hot forming shown in Figure 4, side cut and punching hole composite die tool.
Wherein: 1, holding pad, 2, last side cut instrument, 3, following side cut instrument, 4, push rod, 5, the shaping die, 6, following side cut oil cylinder, 6a, upper oil hole, 6b, following oilhole, 6c, piston rod, 7, following punching oil cylinder, 7a, upper oil hole, 7b, following oilhole, 7c, piston rod, 8, following punching tool, 9, the hot forming part, 10, following side cut oil cylinder, 10a, upper oil hole, 10b, following oilhole, 10c, piston rod, 11, push rod, 12, following side cut instrument, 13, last side cut instrument, 14, last side cut oil cylinder, 14a, upper oil hole, 14b, following oilhole, 14c, piston rod, 15, last punching tool, 16, push rod, 17, last punching oil cylinder, 17a, upper oil hole, 17b, following oilhole, 17c, piston rod, 18, forming terrace die, 19, last side cut oil cylinder, 19a, upper oil hole, 19b, following oilhole, 19c, piston rod, 20, the side cut waste material, 21 punched scraps, 22, forming part.
The specific embodiment
The hot forming of high-duty steel part of the present invention, punching and edge-cutting integrated technique; the punch, die or the holding pad that at first are the hot-forming die of high-duty steel part are provided with corresponding side cut and punching tool, install on punch, die or holding pad and cut edge and hole punched device.The flow process of this technology be the plate that is heated to austenitic state be positioned on the die of hot-forming die → under forcing press drives; holding pad carries out binder to the hot forming plate earlier; punch and die closure then; finish part hot forming → punch; side cut in die or the holding pad and hole punched device motion; finish cutting edge and punching → to punch; the inner cooling medium that feeds of die or holding pad cools off mould; realize the quenching of high strength part; side cut and punching tool reset simultaneously; eject cut edge and waste material that punching forms → under forcing press drives; punch and die are opened, and take out the waste material that hot forming part and side cut and punching form.Hot forming, side cut, the punching operation of high-duty steel part finished in a punching press simultaneously.
Fig. 2, Fig. 3 and Fig. 4 have provided the structure of hot forming, punching and the edge-cutting integrated mould of part shown in a kind of Fig. 1 of being used for a and Fig. 1 b, Fig. 2 and Fig. 4 have provided the mould state before part hot forming punching afterwards and the hot trimming, and Fig. 5 and Fig. 6 have provided the state behind part punching and the hot trimming.This hot forming, side cut and hole-punching integrated mould comprise holding pad 1, go up side cut instrument 2, down side cut instrument 3, down side cut instrument 12, go up side cut instrument 13, down punching tool 8, go up punching tool 15, down side cut oil cylinder 6, down side cut oil cylinder 10, go up side cut oil cylinder 14, go up side cut oil cylinder 19, down punching oil cylinder 7, go up punching oil cylinder 17, push rod 4, push rod 11, push rod 16, forming terrace die 18 and shaping die 5.Forming terrace die 18 and shaping die 5 adopt the disclosed technology of CN101288889, are provided with cooling-water duct (not drawing among Fig. 2) in forming terrace die 18 and shaping die 5.The exterior contour of forming terrace die 18 is consistent with the interior shape of part, and the inner chamber profile of shaping die 5 is consistent with the outer shape of part.Side cut oil cylinder 19 and last side cut oil cylinder 14 are installed on the end face of holding pad 1, and the upper end of forming terrace die 18 is equipped with punching oil cylinder 17, and side cut oil cylinder 6, following side cut oil cylinder 10 and following punching oil cylinder 7 are installed down on the shaping die 5.The piston rod 19c of last side cut oil cylinder 19 links together by screw thread and last side cut instrument 2, the piston rod 14c of last side cut oil cylinder 14 links together by screw thread and last side cut instrument 13, the piston rod 6c of following side cut oil cylinder 6 links together by screw thread and push rod 4, push rod 4 links together by screw thread and following side cut instrument 3, the piston rod 10c of following side cut oil cylinder 10 links together by screw thread and push rod 11, and push rod 11 links together by screw thread and following side cut instrument 12.The piston rod 17c of last punching oil cylinder 17 links together by screw thread and push rod 16, and push rod 16 links together by screw thread and last punching tool 15, and the piston rod 7c of following punching oil cylinder 7 links together by screw thread and following punching tool 8.Forming terrace die 18 and holding pad 1 are fixed on the cope match-plate pattern (not drawing among the figure) by screw, pin, cope match-plate pattern is fixed on the slide block of forcing press again, shaping die 5 is fixed on the lower bolster (not drawing among the figure) by screw and pin, and lower bolster is fixed on the workbench of forcing press again.
In the hot forming process, forming terrace die 18 and holding pad 1 move downward under press ram and cope match-plate pattern drive, holding pad 1 contact earlier is positioned over the high-strength steel sheet that is heated to austenitic state of counterdie 5 upper surfaces, the elasticity material pressing device (not drawing among the figure) that is provided with on holding pad 1 end face will compress, thereby the high strength plate is carried out binder, avoid plate in forming process, to produce defectives such as wrinkling, continue in the descending process at press ram, the high-strength steel sheet that forming terrace die 18 will be heated to austenitic state is pressed in the shaping die 5, make high-strength plate at the mould internal shaping, form the hot forming part 9 of untouched edge punching.
After the part forming, piston rod 19c drives of side cut oil cylinder 19 gone up side cut instrument 2 and moved downward on the auxiliary supporting HYDRAULIC CONTROL SYSTEM, and piston rod 6c drive push rod 6, time side cut instrument 3 of side cut oil cylinder 6 moves downward under the HYDRAULIC CONTROL SYSTEM simultaneously; Piston rod 14c drives of side cut oil cylinder 14 gone up side cut instrument 13 and moved downward on the auxiliary supporting HYDRAULIC CONTROL SYSTEM, and piston rod 10c drive push rod 11, time side cut instrument 12 of side cut oil cylinder 10 moves downward under the HYDRAULIC CONTROL SYSTEM simultaneously; Shaping die 5 upper surfaces, on side cut instrument 2, down side cut instrument 3, on side cut instrument 13, down under the acting in conjunction of side cut instrument 12, the waste material 20 that hot trimming forms separates from the hot forming part 9 of waiting to cut edge, thereby finishes mould inside hot trimming process.Punching tool 8 moved upward under the piston rod 7c of punching oil cylinder 7 drove under the auxiliary supporting HYDRAULIC CONTROL SYSTEM, the piston rod 17c of punching oil cylinder 17 drives push rod 16 on the HYDRAULIC CONTROL SYSTEM simultaneously, upward punching tool 15 moves upward, forming terrace die 18 lower surfaces, on punching tool 15, down under the acting in conjunction of punching tool 8, the waste material 21 that hot piercing forms separates from the hot forming part 9 for the treatment of punching, thereby finishes mould inside hot piercing process.In high-duty steel part hot piercing and hot trimming process, hot piercing technology and hot trimming technology are carried out simultaneously at mould inside.
After hot trimming and hot piercing are finished, in the cooling water channel of forming terrace die 18 and shaping die 5, feed cooling medium, mould is cooled off, thereby formation of parts is quenched.When in mould, feeding cooling water, side cut oil cylinder 6 under the auxiliary supporting HYDRAULIC CONTROL SYSTEM, down side cut oil cylinder 10, go up side cut oil cylinder 14, go up side cut oil cylinder 19 drive corresponding side cut instrument along with the direction operation of cutting edge opposite, following punching oil cylinder 7, last punching oil cylinder 17 drive punching tools along the direction operation opposite with punching, the side cut waste material 20 that forms of cutting edge is ejected from shaping die 5, and the punched scrap 21 that punching is formed ejects from forming terrace die 18.After formation of parts finished cooling, press ram moved upward, under cope match-plate pattern drives, forming terrace die 18 and holding pad 1 move upward, mould is opened, and side cut waste material 20, punched scrap 21 and forming part 22 are taken out mould, enters next working cycles then.
The side cut operation needs and will all downcut around high strength steel wait the to cut edge waste material of hot forming part 9 peripheries, for the smooth implementation of the operation that guarantees to cut edge, simplifies the design of side cut instrument, to side cut instrument employing block form as shown in figure 10.The peripheral profile of high-duty steel part may be an arbitrary curve, and the piecemeal quantity of following side cut instrument is according to the complicated process decision of high-duty steel part, and last side cut instrument is identical with the piecemeal quantity of following side cut instrument.Several boundary lines (chain-dotted line among Fig. 3) that will exceed high-duty steel part are arranged in all piecemeals of side cut instrument, waste material can be divided into several after guaranteeing to cut edge, be convenient to the taking-up of waste material.The thickness of side cut instrument generally determines that according to the wall thickness of the high strength part that is shaped the thickness of side cut instrument is 1.5~4.0 times of part wall thickness, for the high strength part of sheet moulding, and capping, the high strength part for cut deal is shaped takes off limit.In the side cut process, last side cut instrument by with holding pad 1 in corresponding installing hole lead, following side cut instrument by with shaping die 5 in corresponding installing hole lead.
The general length of side cut instrument of monolithic is bigger, if apply side cut power for the side cut instrument with an oil cylinder, will cause side cut power deficiency or side cut instrument in the side cut process because of unbalance stress causes deflection, accelerate the rate of wear of side cut instrument and mould.In order to address this is that, as Fig. 4 and shown in Figure 6, size according to last side cut instrument 2, last side cut instrument 13 or following side cut instrument 3,12, adopt plural upper mould oil cylinder or lower mold oil cylinder to provide side cut power for the side cut instrument, and oil cylinder is uniform along the side cut instrument, guarantee to the side cut instrument provides enough big side cut power, and guarantee side cut instrument stress equalization, avoid deflection.Link together for last side cut instrument 2 provides the upper oil hole 19a of a plurality of upper mould oil cylinders 19 of power, following oilhole 19b links together, and guarantees that a plurality of oil cylinders of patrix can move simultaneously; Link together for last side cut instrument 13 provides the upper oil hole 14a of a plurality of upper mould oil cylinders 14 of power, following oilhole 14b links together, and guarantees that a plurality of oil cylinders of patrix can move simultaneously; For following side cut instrument 3 provides the upper oil hole 6a of a plurality of lower mold oil cylinder 6 of power to link together, following oilhole 6b links together, and guarantees that a plurality of lower mold oil cylinder can move simultaneously; For following side cut instrument 12 provides the upper oil hole 10a of a plurality of lower mold oil cylinder 10 of power to link together, following oilhole 10b links together, and guarantees that a plurality of lower mold oil cylinder can move simultaneously.