WO2023087631A1 - 一种摩擦增材制坯的装置及其方法 - Google Patents

一种摩擦增材制坯的装置及其方法 Download PDF

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Publication number
WO2023087631A1
WO2023087631A1 PCT/CN2022/090858 CN2022090858W WO2023087631A1 WO 2023087631 A1 WO2023087631 A1 WO 2023087631A1 CN 2022090858 W CN2022090858 W CN 2022090858W WO 2023087631 A1 WO2023087631 A1 WO 2023087631A1
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Prior art keywords
tool head
transmission shaft
annular
friction
cylinder
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PCT/CN2022/090858
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English (en)
French (fr)
Inventor
吴护林
李忠盛
黄树海
戴明辉
肖寒
陈强
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西南技术工程研究所
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Priority claimed from CN202111387292.5A external-priority patent/CN113977068B/zh
Priority claimed from CN202111387268.1A external-priority patent/CN113977067A/zh
Application filed by 西南技术工程研究所 filed Critical 西南技术工程研究所
Publication of WO2023087631A1 publication Critical patent/WO2023087631A1/zh

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
    • B23K20/12—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by friction; Friction welding

Definitions

  • the invention relates to the technical field of friction equipment, in particular to a device and method for making blanks by friction additives.
  • the document CN109202273A discloses a wire-filling friction-stir additive manufacturing device and additive manufacturing method.
  • the device includes a stirring pin, a tool head, a wire material, and a substrate.
  • the tool head rotates and moves on the surface of the substrate to be added.
  • the needle pushes the wire through the through hole of the tool head to fill the wire; the specific steps are: first insert the stirring needle into the axial through hole of the tool head, and push the front end of the wire until it touches the inner wall of the tool head.
  • the stirring head composed of needles is placed on the surface of the substrate to be added, and the end of the wire is thermally plasticized under the friction of the axial through hole wall inside the tool head. Material stacking.
  • Document CN112496522A discloses a friction stir additive device and additive manufacturing method, including a tool head, a tool handle and a bushing, the bushing is set on the tool head and the tool handle, and drives the tool head to rotate through the main shaft, and the tool head and the knife There is a connected hollow cavity in the shank for adding wire, so as to realize friction stir additive manufacturing.
  • the friction welding equipment in the prior art or the above-mentioned friction additive equipment all use rigid tool heads. Since the tool head is a rigid structure, it bears a lot of load and wears during the working process. The working environment of the tool head is harsh, and the tool head wears seriously. , the service life is low, and at the same time affect the forming quality of additive products.
  • the object of the present invention is to provide a device and method for friction additive billet manufacturing, so as to solve the problems of low tool life and low internal structure density of the billet.
  • the present invention provides a device for making blanks by friction additives, which includes a formwork structure, a rotating structure and a tool head, and is characterized in that: the rotating structure includes a rotating mechanism and a transmission shaft, and the rotating mechanism passes through The transmission key drives the transmission shaft to rotate, and the transmission shaft is axially separated from the rotation mechanism with a gap for the transmission shaft to move in the axial direction, the transmission shaft is connected to the tool head, and the A floating structure is sheathed on the outer side of the transmission shaft, and is connected to the formwork structure through the floating structure, and the transmission shaft and the tool head slide in the axial direction along with the floating structure.
  • the floating mechanism includes a hydraulic cylinder and a two-way thrust angular contact bearing
  • the hydraulic cylinder is connected to the transmission shaft through a two-way thrust angular contact bearing
  • the two-way thrust angular contact The inner ring of the bearing is fixed on the transmission shaft
  • the hydraulic cylinder includes an annular cylinder, an annular plunger and a stud
  • the annular plunger is inserted in the annular cylinder to form a closed cavity chamber
  • the ring-shaped plunger is fixedly connected to the formwork structure through a double-headed stud.
  • the transmission shaft When the bearing capacity of the tool head is greater than the rated pressure of the hydraulic cylinder, the transmission shaft cannot float, and the bearing capacity will be directly It is transmitted to the rotating mechanism; when the bearing capacity of the tool head is less than the rated pressure of the hydraulic cylinder, the transmission shaft and its tool head will slide relative to each other in the axial direction synchronously.
  • the formwork structure includes an upper formwork, a gasket and a support plate, the washers are symmetrically distributed in the inner holes of the lower end surface of the upper formwork, and the lower end surface of the gasket is placed on the upper surface of the support plate The end face, and tightly connect the upper formwork, the washer and the support plate through bolts, and the support plate is connected to the annular plunger through the double-ended studs.
  • symmetrically distributed transmission keys are inlaid between the inner hole of the lower end surface of the rotating mechanism and the flange through hole of the transmission shaft, and the lower end surface of the transmission shaft is connected with the upper end surface of the tool head.
  • a pipe joint is provided on the lower surface of the annular cylinder, and the pipe joint communicates with the chamber, and the inner and outer sides of the annular plunger are respectively inlaid with upper O-rings , a guide ring and a lower O-ring, the annular cylinder slides axially relative to the annular plunger along the guide ring.
  • the material of the upper O-ring and the lower O-ring is oil-resistant rubber material
  • the material of the guide ring 18 is polytetrafluoroethylene.
  • the upper end surface of the annular cylinder is connected with a cylinder cover, and the double-ended studs pass through the cylinder cover to connect with the annular plunger.
  • a dust-proof cover and a dust-proof sealing ring are sheathed on the stud, and the dust-proof cover and the dust-proof sealing ring are attached to the upper end surface of the cylinder head.
  • the rotating mechanism, transmission shaft and tool head are connected hollow structures.
  • annular shell is sheathed on the outside of the tool head, and a cooling water system and a gas protection system are arranged inside the annular shell, and the annular shell, the fixed ring and the annular cylinder are connected into one body.
  • a method for friction additive blanking characterized in that it comprises the following steps:
  • Step 1 feeding the blank into the cavity of the mold below the tool head along the axial direction of the tool head;
  • Step 2 pre-compacting the billet
  • Step 3 the tool head rotates while pressing down in the axial direction
  • Step 4 the tool head leaves the blank axially upward;
  • Step 5 repeat steps 1-4 one or more times.
  • the rotation speed of the tool head in step 3 is 100rpm-3000rpm
  • the pressing speed is 0.1mm/min-5mm/min
  • the height of the preform is 0.2mm-3mm, which is conducive to the densification of the blank structure.
  • step 2 inert gas protection is introduced into the tool head until the preparation is completed in order to prevent the blank from oxidation.
  • the method of friction additive billet making specifically includes the following steps:
  • Step 1 feed the blank with a powder particle size of 100um to 400um along the axial direction of the upper mold base, the rotating mechanism, the transmission shaft and the internal through hole of the tool head, and transport the powder into the steel plate slot hole, and the hydraulic cylinder
  • the set initial working pressure value
  • Step 2 injecting inert gas protection into the tool head, controlling the tool head to axially load the billet in the axial direction, so as to promote the pre-compaction of the material, and maintain the pressure radially to obtain the height of the preform;
  • Step 3 control the tool head to axially load the blank along the axial direction, and at the same time, the rotating mechanism drives the tool head to rotate at a high speed and maintain pressure radially, and the tool head adjusts the axial direction in real time according to the thickness change of the blank. bearing capacity and relative position;
  • Step 4 the tool head leaves the blank axially upward;
  • Step 5 repeat steps 1-4 one or more times.
  • the working speed of the hydraulic oil is 0-10mm/s, and the working pressure is 0-10MPa.
  • the parameter ratio setting of the total reduction H2 of the tool head to the height H1 of the preform satisfies this formula: 0.35 ⁇ H2/H1 ⁇ 0.85.
  • the present invention provides a device and method for making blanks by friction additive materials.
  • the floating mechanism can adjust the tool head and the rotating mechanism in real time according to the change of the thickness of the blank. Relative axial speed and displacement, when the feeding amount is large, the tool head will automatically reduce the reduction to ensure that the deformation is large enough to achieve the effect of plasticizing the blank; when the feeding amount is small, the tool head will automatically go down larger, Press the blank more firmly.
  • the relative position of the tool head is controlled in real time during the whole process, and at the same time, the compactness of the blank structure is provided to reduce the generation of flash;
  • the tool head has the function of rotation and floating, and is easy to integrate into friction welding, friction stir welding, friction additives and other equipment, installation and debugging Convenient;
  • the axial bearing capacity and relative position of the tool head can be adjusted in real time according to the change of the actual blank thickness, so as to improve the working environment and stress state of the tool head, avoid vibration and wear of the tool head, and prolong the service life and forming of the tool head Quality, improve manufacturing level, has a wide range of application value in aluminum alloy, magnesium alloy, alloy steel and other materials.
  • the blank is subjected to the joint action of the axial pressure and the rotational friction pressure, and the blank undergoes severe plastic deformation to ensure the densification of the blank structure, and by controlling the relationship between the total reduction of the friction additive tool head and the height of the preform , can obtain high-performance blanks with high structure density and few quality defects, and have a wide range of application values in aluminum alloys, magnesium alloys, alloy steels and other materials.
  • the traditional rigid tool head when the thickness of the blank is large, the real-time deformation is large, and it is easy to happen that the rigid tool head cannot press the blank, and the tool head trembles, causing the actual deformation to not reach the deformation of the blank design.
  • the pressure is not firm, the structure is not dense and plasticized, and defects such as holes and gaps are prone to occur inside, which affects the forming performance;
  • Fig. 1 is a schematic structural view of the device for making blanks by friction additives in Example 1;
  • Fig. 2 is a schematic structural view of the device for friction additive billet making in Example 2;
  • Fig. 3 is the side view of support plate
  • Fig. 4 is the top view of support plate
  • Figure 5 is a side view of the cylinder head
  • Figure 6 is a top view of the cylinder head
  • Figure 7 is a side view of the retaining ring
  • Figure 8 is a top view of the retaining ring
  • Fig. 9 is the metallographic diagram of the aluminum alloy billet structure of embodiment 2.
  • Fig. 10 is the metallographic diagram of the aluminum alloy billet structure of embodiment 3.
  • Fig. 11 is a schematic diagram of the total reduction H2 of the tool head and the height H1 of the preform in Embodiment 1 and Embodiment 2;
  • Fig. 12 is a schematic diagram of preparing a multi-layer blank.
  • a device for friction additive blanking includes a formwork structure, a rotating structure and a tool head 22, the rotating structure drives the tool head 22 to rotate, and the rotating structure includes a rotating mechanism 13 And the transmission shaft 14, the lower end surface of the rotating mechanism 13 is screwed to the transmission key 15, and the transmission key 15 is used to drive the transmission shaft 14 to rotate, and the upper end surface of the transmission shaft 14 is axially connected to the lower end surface of the rotation mechanism 13.
  • the transmission shaft 14 is connected to the tool head 22, and both are solid structures, and the outer side of the transmission shaft 14 is sleeved with a floating structure,
  • the formwork structure is connected through the floating structure, the transmission shaft 14 and the tool head 22 move in the axial direction with the floating structure, and the floating mechanism includes a hydraulic cylinder and a two-way thrust angular contact bearing 4, so The inside of the hydraulic cylinder is connected to the transmission shaft 14 through a two-way thrust angular contact bearing 4, and the inner ring of the two-way thrust angular contact bearing 4 is locked on the transmission shaft 14 by a lock nut 3.
  • the hydraulic cylinder includes an annular cylinder Body 5, annular plunger 6 and stud 9, the annular cylinder 5 is inserted with the annular plunger 6, and forms a closed chamber 20, hydraulic oil is arranged in the chamber 20, so The annular plunger 6 is fixedly connected to the formwork structure through the double-headed stud 9.
  • the transmission shaft 14 cannot float, and the bearing will be directly The force is transmitted to the rotating mechanism 13; when the carrying capacity of the tool head 22 is less than the rated pressure of the hydraulic cylinder, the transmission shaft 14 and its tool head 22 will slide relative to each other in the axial direction synchronously.
  • the formwork structure includes an upper formwork 12, a gasket 11 and a support plate 10, the upper formwork 12 does not rotate, and the washers 11 are symmetrically distributed in the inner hole of the lower end surface of the upper formwork 12, and the washer 11
  • the lower end surface is placed on the upper end surface of the support plate 10, and the upper formwork 12, the gasket 11 and the support plate 10 are tightly connected by bolts, and the double-ended studs 9 are evenly distributed in the support plate 10, and the double-ended The studs 9 tightly connect the support plate 10 with the annular plunger 6 .
  • Symmetrically distributed transmission keys 15 are inlaid between the inner hole of the lower end surface of the rotating structure and the flange through hole of the transmission shaft 14, the lower end surface of the transmission shaft 14 is connected with the upper end surface of the tool head 22, and the The key 15 transmits the torque of the rotating mechanism 13 to the transmission shaft 14 and the tool head 22; the transmission key 15 has threaded holes inside, and the symmetrically distributed transmission keys 15 are tightly connected to the rotating mechanism 13 by bolts .
  • the upper end surface of the annular cylinder 5 is connected with a cylinder cover 7, and the cylinder cover 7 locks the bidirectional thrust angular contact bearing 4 together with the lock nut 3, and the double-ended stud 9 passes through the
  • the cylinder head 7 is connected to the annular plunger 6, and the double-ended stud 9 is provided with a dustproof cover 8 and a dustproof sealing ring 16, and the dustproof cover 8 and the dustproof sealing ring 16 are attached to the cylinder.
  • the upper end surface of the cover 7, the lower end surface of the annular cylinder 5 is provided with a pipe joint 21, the pipe joint 21 communicates with the chamber 20, hydraulic oil enters and exits the chamber 20 through the pipe joint 21, and the annular column
  • the inner and outer sides of the plug 6 are respectively inlaid with an upper O-ring 17, a guide ring 18 and a lower O-ring 19, and the annular cylinder 5 slides axially relative to the annular plunger 6 along the guide ring 18, so that
  • the material of the above O-shaped sealing ring 17 and the lower O-shaped sealing ring 19 is oil-resistant rubber material, and the material of the guide ring 18 is polytetrafluoroethylene.
  • the working speed of the hydraulic oil is 0-10mm/s, and the working pressure is 0-10MPa.
  • the tool head 22 is a solid structure, suitable for friction stir welding, and its working process includes the following stages:
  • the bearing capacity changes according to the actual bearing capacity of the tool head 22, and drives the annular cylinder 5 to slide relative to the axial direction, thereby driving the transmission shaft 14 and the tool head 22 to slide relative to the axial direction synchronously; when the When the bearing capacity of the tool head 22 is greater than the rated pressure of the hydraulic cylinder, the transmission shaft 14 cannot float at this time, and the upper end surface of the flange of the transmission shaft 14 is closely attached to the lower end surface of the rotating mechanism 13, and the bearing capacity is directly transmitted to The rotating mechanism 13;
  • the rotating mechanism 13 , the drive shaft 14 and the tool head 22 are hollow structures connected with each other, and an annular shell is pierced on the outside of the tool head 22 body 1, a cooling water system and a gas protection system are set in the annular housing 1, the cooling water system includes a water inlet and a water outlet, the water flows around the tool head 22, and the gas protection system includes an air inlet and a water outlet An air outlet, the air outlet faces the working direction of the tool head 22, and is used for cooling the tool head 22 and preventing the influence of oxidation inclusions.
  • the annular housing 1, the fixed ring 2 and the annular cylinder 5 are connected as one.
  • the tool head 22 is a hollow structure, suitable for friction additives, and its working process includes the following stages:
  • the tool head 22 can adjust the axial bearing capacity and relative position of the tool head 22 in real time according to the thickness change of the blank during the process of pressing down and rotating the tool head 22 in the axial direction, improving the tool
  • the working environment and stress state of the tool head 22 can improve the service life and forming quality of the tool head 22, and reduce the generation of flash;
  • Layer-by-layer accumulative material addition stage Repeat the above-mentioned single-layer friction additive process, that is, continue to start the friction additive material of a new layer of material on the surface of the friction additive material blank, so that layer by layer friction Add material to make blanks, and finally prepare blanks that reach the expected height;
  • the specific steps of the method for friction additive blanking include:
  • Step 1 the blank (7A04 aluminum alloy powder) is fed axially along the inner through holes of the upper mold frame 12, the rotating mechanism 13, the transmission shaft 14 and the tool head 22, and the powder is transported to a steel plate slot with an inner hole diameter of 40mm Among them, the particle size of the blank is about 300um, and the annular cylinder 5, annular plunger 6, and stud 9 on the tool head 22 form a hydraulic cylinder, and the initial working pressure set in the hydraulic cylinder is 4.8MPa ;
  • Step 2 then the tool head 22 contacts the material at a speed of 0.5 mm/min and then presses the material downward along the axial direction, pre-compacts the material, and holds the pressure for 6 seconds, so that the height H1 of the preform is 2.6 mm;
  • Step 3 control the tool head 22 to continue axial loading at a speed of 3 mm/min, and at the same time the tool head rotates at a high speed of 1000 rpm, the total reduction of the tool head 22 is 1.5 mm, and the pressure is kept for 6 seconds.
  • Step 4 the tool head 22 leaves the blank upward along the axial direction;
  • Step 5 repeat the above steps 1-4 twice to obtain a blank with a total thickness of about 3.3mm.
  • Step 1 the blank (40Cr alloy steel powder) is fed axially along the inner through holes of the upper mold frame 12, the rotating mechanism 13, the transmission shaft 14 and the tool head 22, and the blank is transported to a steel plate slot with an inner hole diameter of 40mm Among them, the particle size of the billet is about 100um, the annular cylinder 5 on the tool head 22, the annular plunger 6, and the double-ended stud 9 form a hydraulic cylinder, and the initial working pressure set in the hydraulic cylinder is 5.7MPa;
  • Step 2 Introduce argon gas protection into the tool head 22, and then the tool head 22 contacts the material at a speed of 0.5 mm/min and presses the material downward along the axial direction to pre-compact the material and hold the pressure for 10 seconds to obtain a preform
  • the height H1 is 1.5mm;
  • Step 4 the tool head 22 leaves the blank upward along the axial direction;
  • Step 5 repeat the above steps 1-4 twice to obtain a blank with a total thickness of about 3mm.

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  • Mechanical Engineering (AREA)
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Abstract

提供一种摩擦增材制坯的装置及其方法，包括模架结构、旋转机构（13）、传动轴（14）和工具头（22），旋转机构（13）驱动工具头（22）旋转，旋转机构（13）通过传动键（15）驱动传动轴（14）旋转，传动轴（14）与旋转机构（13）轴向分离且留有间隙，供传动轴（14）在轴向方向上活动，传动轴（14）连接工具头（22），传动轴（14）外侧套设有浮动结构，并通过浮动结构连接模架结构，传动轴（14）与工具头（22）随浮动结构在轴向方向上滑动，工具头（22）总的压下量H2与预制坯高度H1参数比值设置满足此公式：0.35＜H2/H1＜0.85，具有工具头（22）使用寿命长和坯料成形质量好的优点。

Description

一种摩擦增材制坯的装置及其方法 技术领域
本发明涉及摩擦设备技术领域，具体为一种摩擦增材制坯的装置及其方法。
背景技术
目前，文献CN109202273A公开了一种填丝搅拌摩擦增材制造装置及增材制造方法，该装置包括搅拌针、工具头、丝材和基体，工具头在基体待增材区表面旋转并移动，搅拌针推动丝材通过工具头的通孔进行填丝；具体步骤为：先将搅拌针插入工具头的轴向通孔内，并推动将丝材前端接触到工具头内壁为止，将工具头和搅拌针组成的搅拌头置于在基体待增材区表面，丝材端部在工具头内部的轴向通孔壁的摩擦作用下发生热塑化，待增材区单层材料堆覆或多层材料堆覆。
上述文献公开的增材方法，其工具头处于大载荷的加持下的状态下，工具头摩擦坯料，坯料会发生剧烈塑性变形，但无法得到组织致密性高、质量缺陷少的高性能坯料。
文献CN112496522A公开了一种搅拌摩擦增材装置及增材制造方法，包括工具头、刀柄以及轴套，轴套套设在工具头和刀柄上，并通过主轴驱动工具头旋转，工具头和刀柄内有连通的中空腔体用于添丝，从而实现搅拌摩擦增材制造.
现有技术中的摩擦焊接设备或采用上述的摩擦增材设备都是采用的刚性工具头，由于工具头是刚性结构，在工作过程中承受载荷磨损大，工具头工作环境恶劣，工具头磨损严重，使用寿命较低，同时影响增材产品成形质量。
发明内容
本发明的目的在于提供一种摩擦增材制坯的装置及其方法，以解决工具头寿命低和坯料的内部组织致密度低的问题。
为了达到上述目的，本发明提供了一种摩擦增材制坯的装置，包括模架结构、旋转结构和工具头，其特征在于：所述旋转结构包括旋转机构和传动轴，所述旋转机构通过传动键驱动所述传动轴旋转，所述传动轴与所述旋转机构轴向分离且留有间隙，供所述传动轴在轴向方向上活动，所述传动轴连接所述工具头，所述传动轴外侧套设有浮动结构，并通过所述浮动结构连接所述模架结构，所述传动轴与工具头随所述浮动结构在轴向方向上滑动。
进一步的，为了使所述工具头自动的上下浮动，所述浮动机构包括液压缸和双向推力角接触轴承，所述液压缸通过双向推力角接触轴承连接所述传动轴，所述双向推力角接触轴承内圈被固定在所述传动轴上，所述液压缸包括环形缸体、环形柱塞和双头螺柱，所述环形 缸体内插设有所述环形柱塞，并形成密闭的腔室，所述环形柱塞过双头螺柱固定连接在所述模架结构上，当所述工具头承载力大于所述液压缸的额定压力时，所述传动轴不能浮动，直接将承载力传递给所述旋转机构；当所述工具头承载力小于液压缸的额定压力时，所述传动轴及其工具头同步做轴向的相对滑动。
为了便于连接和安装，所述模架结构包括上模架、垫圈和支撑板，所述垫圈对称分布在所述上模架下端面的内孔中，所述垫圈下端面置于支撑板的上端面，并通过螺栓将上模架、垫圈和支撑板紧密连接，所述支撑板通过所述双头螺柱连接所述环形柱塞。
进一步为了便于传动，所述旋转机构下端面内孔与传动轴的法兰通孔之间镶嵌有对称分布的传动键，所述传动轴的下端面与所述工具头的上端面连接。
为了防止环形柱塞底部的液压油泄漏，所述环形缸体下端面设置有管接头，所述管接头连通所述腔室，所述环形柱塞的内侧和外侧分别镶嵌有上O型密封圈、导向环和下O型密封圈，所述环形缸体沿着导向环与环形柱塞做轴向相对滑动。
进一步的，为更有效的防漏，所述上O型密封圈与下O型密封圈的材料为耐油橡胶材料，导向环18的材料为聚四氟乙烯。
为保证所述环形缸体内腔体的密闭性，所述环形缸体上端面连接有缸盖，所述双头螺柱穿设过所述缸盖连接所述环形柱塞，所述双头螺柱上套设有防尘盖与防尘密封圈，所述防尘盖与防尘密封圈贴合住所述缸盖上端面。
为了适用于摩擦增材时轴向送料，所述旋转机构、传动轴和工具头为相连通的空心结构。
为了提高成形质量，所述工具头外侧套设有环形壳体，所述环形壳体内设置冷却水系统和气体保护系统，所述环形壳体、固定圈和环形缸体连接成一体。
一种摩擦增材制坯的方法，其特征在于，包括以下步骤：
步骤1，将坯料沿所述工具头的轴向送入所述工具头下方模具的腔体内；
步骤2，将坯料预压实；
步骤3，所述工具头在沿轴向往下压同时旋转；
步骤4，所述工具头沿轴向向上离开坯料；
步骤5，重复一次或多次步骤1-4。
优选的，步骤3中所述工具头转速为100rpm～3000rpm，下压速度为0.1mm/min～5mm/min，预制坯高度为0.2mm～3mm，有利于坯料组织致密化。
在步骤2开始前，为防止坯料氧化，向所述工具头中通入惰性气体保护直至制备完成。
进一步的保证坯料成型，摩擦增材制坯的方法具体包括以下步骤：
步骤1，将粉末粒径为100um～400um的坯料，沿轴向的所述上模架、旋转机构、传动轴和工具头内部通孔送料，将粉末输送到的钢板槽孔中，液压缸内设定的初始工作压力值；
步骤2，在所述工具头中通入惰性气体保护，控制工具头沿轴向对坯料进行轴向加载，促使材料预压实成形，并径向保压，得到预制坯的高度；
步骤3，控制所述工具头沿轴向对坯料进行轴向加载，同时所述旋转机构驱动所述工具头高速旋转，并径向保压，所述工具头根据坯料厚度变化而实时调整轴向承载力和相对位置；
步骤4，所述工具头沿轴向向上离开坯料；
步骤5，重复一次或多次步骤1-4。
为控制液压缸的上浮速度与距离，液压油的工作速度为0～10mm/s，工作压力为0～10MPa。
为进一步提高坯料的组织致密化，所述工具头总的压下量H2与预制坯高度H1参数比值设置满足此公式：0.35＜H2/H1＜0.85。
有益效果在于：本发明提供一种摩擦增材制坯的装置及其方法，工具头在沿轴向往下压和旋转的过程中，浮动机构能够根据坯料厚度变化而实时调整工具头和旋转机构相对的轴向速度和位移，当送料量大时，工具头会自动降低压下量，保证变形量足够大，以达到坯料塑化的效果；当送料量小时，工具头会自动下行大些，把坯料压的更结实。整个过程实时控制工具头的相对位置，同时提供了坯料组织致密度，减少产生飞边；工具头具有旋转和浮动功能，容易集成于摩擦焊、搅拌摩擦焊、摩擦增材等设备中，安装调试方便；同时能够根据实际坯料厚度的变化而实时调整工具头的轴向承载力和相对位置，改善工具头工作环境和受力状态，避免工具头发生震颤和磨损，延长工具头的使用寿命和成形质量，提高制造水平，在铝合金、镁合金、合金钢等材料中具有广泛的应用价值。
摩擦增材过程中坯料在轴向压力和旋转摩擦压力的共同作用，坯料发生剧烈塑性变形，保证坯料的组织致密化，且通过控制摩擦增材工具头总的压下量与预制坯高度的关系，能够获得组织致密性高、质量缺陷少的高性能坯料，在铝合金、镁合金、合金钢等材料中具有广泛的应用价值。传统的刚性工具头，当坯料厚度较大时，实时变形量大，容易发生刚性工具头压不动坯料的情况，工具头产生震颤，造成实际变形量达不到坯料设计的变形量，坯料内部压不结实，组织不致密、不塑化，内部容易发生孔洞、间隙等缺陷，影响成形性能；本发明设计了工具头，工具头能调节实时的下行位移，即实时调节变形量，若送料量多，工具头压下量自行变小，保证变形量足够大，达到坯料塑化的效果；若送料量少，工具头压下量自 行变大，保证坯料内部压实致密且塑化，并减少内部缺陷、外部飞边，提升坯料整体质量；工具头总的压下量H2与预制坯高度H1的比值α＝H2/H1为0.35～0.85，在相同比值α的条件下，减小预制坯高度H1，有利于坯料组织致密化。
附图说明
图1为本实施例1中摩擦增材制坯的装置的结构示意图；
图2为实施例2中摩擦增材制坯的装置的结构示意图；
图3为支撑板的侧视图；
图4为支撑板的俯视图；
图5为缸盖的侧视图；
图6为缸盖的俯视图；
图7为固定圈的侧视图；
图8为固定圈的俯视图；
图9为实施例2的铝合金坯料组织金相图；
图10为实施例3的铝合金坯料组织金相图；
图11为实施例1和实施例2中工具头总的压下量H2与预制坯高度H1的示意图；
图12为制备多层坯料的示意图。
附图标记：1、环形壳体；2、固定圈；3、锁紧螺母；4、双向推力角接触轴承；5、环形缸体；6、环形柱塞；7、缸盖；8、防尘盖；9、双头螺柱；10、支撑板；11、垫圈；12、上模架；13、旋转机构；14、传动轴；15、传动键；16、防尘密封圈；17、上O型密封圈；18、导向环；19、下O型密封圈；20、腔室；21、管接头；22、工具头；23、进水口；24、出水口；25、进气口；26、出气口。
具体实施方式
下面结合附图对本发明的具体实施方式作进一步详细的说明，但本发明并不局限于这些实施方式，在不脱离本发明原理的前提下，针对本发明进行的改进也落入本发明权利要求的保护范围内。
实施例1
如图1-8所示，一种摩擦增材制坯的装置，包括模架结构、旋转结构和工具头22，所述旋转结构驱动所述工具头22旋转，所述旋转结构包括旋转机构13和传动轴14，所述旋转机构13下端面螺钉连接传动键15，并通过所述传动键15驱动所述传动轴14旋转，所述传动轴14上端面与所述旋转机构13下端面轴向分离且留有一定间隙，供所述传动轴14在轴向方向上 活动，所述传动轴14连接所述工具头22，且都为实心结构，所述传动轴14外侧套设有浮动结构，并通过所述浮动结构连接所述模架结构，所述传动轴14与工具头22随所述浮动结构在轴向方向上移动，所述浮动机构包括液压缸和双向推力角接触轴承4，所述液压缸内侧通过双向推力角接触轴承4连接所述传动轴14，所述双向推力角接触轴承4内圈被锁紧螺母3锁紧在所述传动轴14上，所述液压缸包括环形缸体5、环形柱塞6和双头螺柱9，所述环形缸体5内插设有所述环形柱塞6，并形成密闭的腔室20，所述腔室20内设置液压油，所述环形柱塞6过双头螺柱9固定连接在所述模架结构上，当所述工具头22承载力大于所述液压缸的额定压力时，所述传动轴14不能浮动，直接将承载力传递给所述旋转机构13；当所述工具头22承载力小于液压缸的额定压力时，所述传动轴14及其工具头22同步做轴向的相对滑动。
所述模架结构包括上模架12、垫圈11和支撑板10，所述上模架12不旋转，所述垫圈11对称分布在所述上模架12下端面的内孔中，所述垫圈11下端面置于支撑板10的上端面，并通过螺栓将上模架12、垫圈11和支撑板10紧密连接，所述支撑板10中均匀分布双头螺柱9，并通过所述双头螺柱9将所述支撑板10与环形柱塞6紧密连接。
所述旋转结构下端面内孔与传动轴14法兰通孔之间镶嵌有对称分布的传动键15，所述传动轴14的下端面与所述工具头22的上端面连接，通过所述传动键15将所述旋转机构13的扭矩传递给所述传动轴14和工具头22；所述传动键15内部带有螺纹孔，通过螺栓将对称分布的所述传动键15与旋转机构13紧密连接。
所述环形缸体5上端面连接有缸盖7，所述缸盖7与所述锁紧螺母3一起锁紧所述双向推力角接触轴承4，所述双头螺柱9穿设过所述缸盖7连接所述环形柱塞6，所述双头螺柱9上套设有防尘盖8与防尘密封圈16，所述防尘盖8与防尘密封圈16贴合住所述缸盖7上端面，所述环形缸体5下端面设置有管接头21，所述管接头21连通所述腔室20，液压油通过所述管接头21进出所述腔室20，所述环形柱塞6的内侧和外侧分别镶嵌有上O型密封圈17、导向环18和下O型密封圈19，所述环形缸体5沿着导向环18与环形柱塞6做轴向相对滑动，所述上O型密封圈17与下O型密封圈19的材料为耐油橡胶材料，导向环18的材料为聚四氟乙烯。
液压油的工作速度为0～10mm/s，工作压力为0～10MPa。
所述工具头22为实心结构，适用于搅拌摩擦焊，其工作过程包括以下阶段：
(1)准备阶段：将所述工具头22及其浮动结构安装在搅拌摩擦焊设备中，在所述环形缸体5、环形柱塞6、双头螺柱9组成的液压缸中接入液压油，使液压系统中保持一定的初始压力， 同时将所述传动轴14与旋转机构13之间预留一定的间隙，使所述工具头22具有旋转和浮动的功能；
(2)工作阶段：搅拌摩擦焊设备的所述旋转机构13向下运动和旋转，从而驱动所述传动轴14和工具头22向下运动和旋转，当所述工具头22与坯料接触时，开始搅拌摩擦焊，实现坯料间的固相连接。当所述工具头22承载力小于液压缸的额定压力时，这时所述传动轴14浮动，所述传动轴14的法兰上端面与旋转机构13的下端面没有接触，所述液压缸内的承载力根据所述工具头22实际承载力而变化，带动所述环形缸体5做轴向相对滑动，从而带动所述传动轴14及其工具头22同步做轴向相对滑动；当所述工具头22承载力大于液压缸的额定压力时，这时所述传动轴14不能浮动，所述传动轴14的法兰上端面与旋转机构13的下端面紧密贴合，直接将承载力传递给所述旋转机构13；
(3)结束阶段：坯料间的固相连接完成后，将所述环形缸体5、环形柱塞6、双头螺柱9组成的液压缸中的液压卸载，所述旋转机构13停止旋转，同时驱动所述旋转机构13向上运动到达预设的位置，搅拌摩擦焊工艺结束。
实施例2
如图2所示，参照实施例1的摩擦增材制坯的装置，所述旋转机构13、传动轴14和工具头22为相连通的空心结构，所述工具头22外侧穿设有环形壳体1，所述环形壳体1内设置冷却水系统和气体保护系统，所述冷却水系统包括进水口和出水口，水流围绕所述工具头22流动，所述气体保护系统包括进气口和出气口，所述出气口朝所述工具头22工作方向，用于工具头22进行冷却，以及防止氧化夹杂的影响，所述环形壳体1、固定圈2和环形缸体5连接成一体。
所述工具头22为空心结构，适用于摩擦增材，其工作过程包括以下阶段：
(1)准备阶段：将所述工具头22及其浮动结构安装在搅拌摩擦焊设备中，在所述环形缸体5、环形柱塞6、双头螺柱9组成的液压缸中接入液压油，使液压系统中保持一定的初始压力，同时将所述传动轴14与旋转机构13之间预留一定的间隙，使所述工具头22具有旋转和浮动的功能；
(2)单层增材阶段：首先所述工具头22中心向下送料到一定高度，然后摩擦增材设备的所述旋转机构13向下运动和旋转，从而驱动所述传动轴14、工具头22向下运动和旋转，当所述工具头22与坯料接触时，所述环形壳体1的内部的循环冷却水系统和气体保护系统开始运行，对所述工具头22进行冷却，以及防止氧化夹杂的影响，成形过程中坯料始终承受着轴向压力和旋转摩擦压力的共同作用，坯料发生剧烈塑性变形，当所述工具头22达到设定的轴向 位置后停止下行，并保压一定时间，完成单层的摩擦增材，所述工具头22向上回程到设定的位置。由于所述工具头22为浮动结构，所述工具头22在沿轴向往下压和旋转的过程中，能够根据坯料厚度变化而实时调整工具头22的轴向承载力和相对位置，改善工具头22工作环境和受力状态，提高工具头22的使用寿命和成形质量，减少飞边产生；
(3)逐层累计增材阶段：重复上述单层摩擦增材工艺过程，即在已摩擦增材坯料的表面，继续开始新一层坯料的摩擦增材，这样一层一层的逐层摩擦增材制坯，最终制备出达到预期高度的坯料；
(4)结束阶段：坯料摩擦增材完成后，所述工具头22中心停止送料，将所述环形缸体5、环形柱塞6、双头螺柱9组成的液压缸中的液压卸载，所述旋转机构13停止旋转，同时驱动所述旋转机构13向上运动到达预设的位置，摩擦增材工艺结束。
摩擦增材制坯的方法具体步骤包括：
步骤1，将坯料(7A04铝合金粉末)沿所述上模架12、旋转机构13、传动轴14和工具头22内部通孔轴向送料，将粉末输送到内孔直径为40mm的钢板槽孔中，坯料的粒径为300um左右，所述工具头22上的环形缸体5、环形柱塞6、双头螺柱9组成液压缸，所述液压缸内设定的初始工作压力为4.8MPa；
步骤2，然后工具头22以0.5mm/min的速度接触材料后沿轴向往下压料，将材料预压实，保压6秒，得到预制坯的高度H1为2.6mm；
步骤3，控制工具头22以3mm/min的速度继续轴向加载，同时工具头以1000rpm的转速高速旋转，工具头22总的压下量1.5mm，保压6秒，工具头22总的压下量H2与预制坯高度H1的比值α(α＝H2/H1)为0.58，制备得到第一层增材坯料；
步骤4，工具头22沿轴向向上离开坯料；
步骤5，重复2次上述步骤1-4，得到总厚度约为3.3mm的坯料。
坯料周边飞边很少，表面成形良好，且内部组织致密度高。
实施例3
如图1和3所示，参照实施例2采用的摩擦增材制坯的装置，不同点在于摩擦增材制坯的方法具体步骤包括：
步骤1，将坯料(40Cr合金钢粉末)沿所述上模架12、旋转机构13、传动轴14和工具头22内部通孔轴向送料，将坯料输送到内孔直径为40mm的钢板槽孔中，坯料的粒径为100um左右，工具头22上的环形缸体5、环形柱塞6、双头螺柱9组成液压缸，液压缸内设定的初始工作压力为5.7MPa；
步骤2，工具头22中通入氩气气体保护，然后工具头22以0.5mm/min的速度接触材料后沿轴向往下压料，将材料预压实，保压10秒，得到预制坯的高度H1为1.5mm；
步骤3：控制工具头22以2mm/min的速度继续轴向加载，同时工具头22以1200rpm的转速高速旋转，工具头总的压下量1mm，保压10秒后，工具头22总的压下量H2与预制坯高度H1的比值α(α＝H2/H1)为0.67，制备得到第一层增材坯料；
步骤4，工具头22沿轴向向上离开坯料；
步骤5，重复2次上述步骤1-4，得到总厚度约为3mm的坯料。
坯料周边飞边很少，表面成形良好，且内部组织致密度高。

Claims (15)

  1. 一种摩擦增材制坯的装置，包括模架结构、旋转结构和工具头(22)，所述旋转结构驱动所述工具头(22)旋转，其特征在于：所述旋转结构包括旋转机构(13)和传动轴(14)，所述旋转机构(13)通过传动键(15)驱动所述传动轴(14)旋转，所述传动轴(14)与所述旋转机构(13)轴向分离且留有间隙，供所述传动轴(14)在轴向方向上活动，所述传动轴(14)连接所述工具头(22)，所述传动轴(14)外侧套设有浮动结构，并通过所述浮动结构连接所述模架结构，所述传动轴(14)与工具头(22)随所述浮动结构在轴向方向上滑动。
  2. 根据权利要求1所述的摩擦增材制坯的装置，其特征在于：所述浮动机构包括液压缸和双向推力角接触轴承(4)，所述液压缸通过双向推力角接触轴承(4)连接所述传动轴(14)，所述双向推力角接触轴承(4)内圈被固定在所述传动轴(14)上，所述液压缸包括环形缸体(5)、环形柱塞(6)和双头螺柱(9)，所述环形缸体(5)内插设有所述环形柱塞(6)，并形成密闭的腔室(20)，所述环形柱塞(6)过双头螺柱(9)固定连接在所述模架结构上，当所述工具头(22)承载力大于所述液压缸的额定压力时，所述传动轴(14)不能浮动，直接将承载力传递给所述旋转机构(13)；当所述工具头(22)承载力小于液压缸的额定压力时，所述传动轴(14)及其工具头(22)同步做轴向的相对滑动。
  3. 根据权利要求1或2所述的摩擦增材制坯的装置，其特征在于：所述模架结构包括上模架(12)、垫圈(11)和支撑板(10)，所述垫圈(11)对称分布在所述上模架(12)下端面的内孔中，所述垫圈(11)下端面置于支撑板(10)的上端面，并通过螺栓将上模架(12)、垫圈(11)和支撑板(10)紧密连接，所述支撑板(10)通过所述双头螺柱(9)连接所述环形柱塞(6)。
  4. 根据权利要求3所述的摩擦增材制坯的装置，其特征在于：所述旋转机构(13)下端面内孔与传动轴(14)的法兰通孔之间镶嵌有对称分布的传动键(15)，所述传动轴(14)的下端面与所述工具头(22)的上端面连接。
  5. 根据权利要求2或4所述的摩擦增材制坯的装置，其特征在于：所述环形缸体(5)下端面设置有管接头(21)，所述管接头(21)连通所述腔室(20)，所述腔室(20)内设有液压油，所述环形柱塞(6)的内侧和外侧分别镶嵌有上O型密封圈(17)、导向环(18)和下O型密封圈(19)，所述环形缸体(5)沿着导向环(18)与环形柱塞(6)做轴向相对滑动。
  6. 根据权利要求5所述的摩擦增材制坯的装置，其特征在于：所述上O型密封圈(17)与下O型密封圈(19)的材料为耐油橡胶材料，导向环(18)的材料为聚四氟乙烯。
  7. 根据权利要求2、4或6所述的摩擦增材制坯的装置，其特征在于：所述环形缸体(5)上端面连接有缸盖(7)，所述双头螺柱(9)穿设过所述缸盖(7)连接所述环形柱塞(6)，所述双头螺柱(9)上套设有防尘盖(8)与防尘密封圈(16)，所述防尘盖(8)与防尘密封圈 (16)贴合住所述缸盖(7)上端面。
  8. 根据权利要求7所述的摩擦增材制坯的装置，其特征在于：所述旋转机构(13)、传动轴(14)和工具头(22)为相连通的空心结构。
  9. 根据权利要求8所述的摩擦增材制坯的装置，其特征在于：所述工具头(22)外侧套设有环形壳体(1)，所述环形壳体(1)内设置冷却水系统和气体保护系统，所述环形壳体(1)、固定圈(2)和环形缸体(5)连接成一体。
  10. 一种摩擦增材制坯的方法，其特征在于，包括以下步骤：
    步骤1，将坯料沿工具头(22)的轴向送入所述工具头(22)下方模具的腔体内；
    步骤2，将坯料预压实；
    步骤3，所述工具头(22)在沿轴向往下压同时旋转；
    步骤4，所述工具头(22)沿轴向向上离开坯料；
    步骤5，重复一次或多次步骤1-4。
  11. 根据权利要求10所述的摩擦增材制坯的方法，其特征在于：步骤3中所述工具头(22)转速为100rpm～3000rpm，下压速度为0.1mm/min～5mm/min，预制坯高度为0.2mm～3mm。
  12. 根据权利要求10或11所述的摩擦增材制坯的方法，其特征在于：在步骤2开始前，向所述工具头(22)中通入惰性气体保护直至制备完成。
  13. 根据权利要求12所述的摩擦增材制坯的方法，其特征在于：
    步骤1具体包括：将粉末粒径为100um～400um的坯料轴向送入输送到钢板槽孔中，液压缸内设定的初始工作压力值；
    步骤2具体包括：在所述工具头(22)中通入惰性气体保护，控制所述工具头(22)沿轴向对坯料进行轴向加载，促使材料预压实成形，并径向保压，得到预制坯的高度；
    步骤3具体包括：控制所述工具头(22)沿轴向对坯料进行轴向加载，同时旋转机构(13)驱动所述工具头(22)高速旋转，并径向保压，所述工具头(22)根据坯料厚度变化而实时调整轴向承载力和相对位置；
    步骤4具体包括：所述工具头(22)沿轴向向上离开坯料；
    步骤5具体包括：重复一次或多次步骤1-4。
  14. 根据权利要求13所述的摩擦增材制坯的装置，其特征在于：液压缸中液压油的工作速度为0～10mm/s，工作压力为0～10MPa。
  15. 根据权利要求14所述的摩擦增材制坯的方法，其特征在于：所述工具头(22)总的压下量H2与预制坯高度H1参数设置满足此公式：0.35＜H2/H1＜0.85。
PCT/CN2022/090858 2021-11-22 2022-05-05 一种摩擦增材制坯的装置及其方法 WO2023087631A1 (zh)

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