Forming system and method of hybrid additive manufacturing and surface coating

Abstract

The present invention belongs to the field of multi-material additive manufacturing (AM), and in particular discloses a forming system and method of hybrid AM and surface coating. The hybrid forming system includes an additive forming device, a laser-assisted cold spraying (LACS) device and a workbench. The additive forming device and the LACS device are located above the workbench. During manufacturing, the additive forming device forms a part to be formed on the workbench layer by layer, and the LACS device performs coating peening treatment on inner and outer surfaces of the part to be formed during the forming process, thereby jointly completing the composite manufacturing of the part to be formed. The present invention makes full use of the rapid prototyping advantage of the short-flow AM process, and integrates the surface coating peening process into the hybrid forming system.

Claims

1. A forming system of hybrid additive manufacturing (AM) and surface coating, comprising an additive forming device, a laser-assisted cold spraying (LACS) device and a workbench, wherein the additive forming device and the LACS device are located above the workbench; during manufacturing, the additive forming device forms a part to be formed on the workbench layer by layer, and the LACS device performs coating peening treatment on inner and outer surfaces of the part to be formed during the forming process, thereby jointly completing the composite manufacturing of the part to be formed; wherein, the LACS device comprises a gas compression and drying unit, a powder storage and feeding unit and a ring-shaped laser unit that are sequentially connected; during manufacturing, a coating powder material in the powder storage and feeding unit is compressed and dried by the gas compression and drying unit, sent to the ring-shaped laser unit, then heated by the ring-shaped laser unit, and coated on the inner and outer surfaces of the part to be formed.

2. The forming system of hybrid AM and surface coating according to claim 1, wherein the powder storage and feeding unit comprises two or more powder storage and feeding tanks.

3. The forming system of hybrid AM and surface coating according to claim 1, wherein a feeding rate of the coating powder material of the powder storage and feeding unit is 40-70 g/min, a powder particle size is 5-60 μm, and a preheating temperature of the coating powder material is 400-800° C.

4. The forming system of hybrid AM and surface coating according to claim 1, further comprising a micro-rolling device and a milling and grinding compound device, wherein the micro-rolling device and the milling and grinding compound device are located above the workbench; the micro-rolling device and the milling and grinding compound device perform finish machining on the part to be formed during the process of forming the part to be formed layer by layer by the additive forming device.

5. A forming method of hybrid AM and surface coating, which is implemented by using a forming system of hybrid additive manufacturing (AM) and surface coating, the forming system comprising an additive forming device, a laser-assisted cold spraying (LACS) device and a workbench, wherein the additive forming device and the LACS device are located above the workbench; during manufacturing, the additive forming device forms a part to be formed on the workbench layer by layer, and the LACS device performs coating peening treatment on inner and outer surfaces of the part to be formed during the forming process, thereby jointly completing the composite manufacturing of the part to be formed; wherein, the LACS device comprises a gas compression and drying unit, a powder storage and feeding unit and a ring-shaped laser unit that are sequentially connected; during manufacturing, a coating powder material in the powder storage and feeding unit is compressed and dried by the gas compression and drying unit, sent to the ring-shaped laser unit, then heated by the ring-shaped laser unit, and coated on the inner and outer surfaces of the part to be formed; the forming method comprising the following steps: S1: presetting an additive forming trajectory and a coating peening trajectory according to a three-dimensional (3D) model of a part to be formed; S2: enabling an additive forming device to form a multi-layer part to be formed on a workbench layer by layer according to the preset additive forming trajectory, and enabling an LACS device to perform coating peening treatment on inner and outer surfaces of the part to be formed according to the preset coating peening trajectory; and, S3: repeating S2 several times until the manufacturing of the part is completed.

6. The forming method of hybrid AM and surface coating according to claim 5; wherein, the method includes compressing and drying a coating powder material in the powder storage and feeding unit using the gas compression and drying unit; sending the coating powder material to the ring-shaped laser unit; heating the coating powder material with the ring-shaped laser unit; and, coating the coating powder material on the inner and outer surfaces of the part to be formed.

7. The forming method of hybrid AM and surface coating of claim 6, wherein the compressing and the drying are performed in two or more powder storage and feeding tanks in the powder storage and feeding unit.

8. The forming method of hybrid AM and surface coating of claim 6, wherein the method further comprises: configuring the powder storage and feeding unit to have a powder feeding rate ranging from 40-70 g/min; selecting the coating powder material to have a particle size ranging from 5-60 μm; and, preheating the coating powder material at a temperature ranging from 400-800° C.

9. The forming method of hybrid AM and surface coating according to claim 5, the method further comprising using a micro-rolling device and a milling and grinding compound device; and, performing finish machining on the part to be formed with the micro-rolling device and the milling and grinding compound device, wherein the finish machining is performed during the process of forming the part to be formed, the forming occurring layer by layer using the additive forming device.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a flowchart of a forming method of hybrid additive manufacturing (AM) and surface coating with according to an example of the present invention.

(2) FIG. 2 is a schematic diagram of a forming system of hybrid AM and surface coating according to an example of the present invention.

(3) FIG. 3 is a structural diagram of servo powder feeding by a plurality of powder feeders according to an example of the present invention.

(4) In all the drawings, the same reference numerals are used to denote the same elements or structures, where: 1. workbench; 2. substrate; 3. milling and grinding compound device; 4. micro-rolling device; 5. part to be formed; 6. inner and outer surfaces of part to be formed; 7. additive forming device; 8. additive forming surface; and 9. laser-assisted cold spraying (LACS) device.

DETAILED DESCRIPTION

(5) To make the objectives, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below with reference to the accompanying drawings and examples. It should be understood that the examples described herein are merely intended to explain the present invention, rather than to limit the present invention. Further, the technical features involved in the various examples of the present invention described below may be combined with each other as long as they do not constitute a conflict with each other.

(6) An example of the present invention provides a forming system of hybrid additive manufacturing (AM) and surface coating. As shown in FIG. 2, the hybrid forming system includes an additive forming device 7, a laser-assisted cold spraying (LACS) device 9 and a workbench 1. The additive forming device 7 and the LACS device 9 are located above the workbench 1, and a substrate 2 is placed on the workbench 1. During manufacturing, the additive forming device 7 forms a part 5 to be formed on the substrate 2 layer by layer, and the LACS device 9 performs coating peening treatment on inner and outer surfaces 6 of the part to be formed during the forming process, thereby jointly completing the composite manufacturing of the part 5 to be formed.

(7) Specifically, as shown in FIG. 3, the LACS device 9 includes a gas compression and drying unit, a powder storage and feeding unit and a ring-shaped laser unit that are sequentially connected. During manufacturing, a coating powder material in the powder storage and feeding unit is compressed and dried by the gas compression and drying unit, sent to the ring-shaped laser unit, then heated by the ring-shaped laser unit, and coated on the inner and outer surfaces 6 of the part to be formed. More specifically, the ring-shaped laser unit includes an LACS gun for surface coating. The LACS gun is used to choose whether to use an auxiliary heating laser and power thereof according to different melting points of coating materials during the coating process, so as to realize the surface coating of materials with different melting points.

(8) Preferably, the powder storage and feeding unit includes two or more powder storage and feeding tanks; a powder feeding rate of the powder storage and feeding unit is 40-70 g/min, a powder particle size is 5-60 μm, and a preheating temperature is 400-800° C.

(9) Further, the hybrid forming device further includes a micro-rolling device 4 and a milling and grinding compound device 3; the micro-rolling device 4 and the milling and grinding compound device 3 are located above the workbench 1; the micro-rolling device 4 and the milling and grinding compound device 3 perform finish machining on the inner and outer surfaces 6 of the part to be formed during the process of forming the part 5 to be formed layer by layer by the additive forming device 7.

(10) Specifically, the hybrid forming device is provided on a five-axis linkage machining center and cooperates with double gantries or mechanical arms to realize short-flow composite AM. The additive forming device 7, the micro-rolling device 4 and the milling and grinding compound device 3 are provided on one gantry or mechanical arm. They are each provided with a lifting device, so that they can work independently and freely switch to a required device. The LACS device 9 is provided on the other gantry or mechanical arm. The workbench 1 can rotate around a C-axis and turn around an A-axis of the machining center, so that a formed surface of the part 5 to be formed is perpendicular to the processing equipment during manufacturing, so as to achieve better forming quality and effect.

(11) As shown in FIG. 1, a hybrid forming method using the above system specifically includes the following steps:

(12) S1: Slice a three-dimensional (3D) computer-aided design (CAD) model of a part 5 to be formed into layers according to a geometrical shape of the part 5 to be formed and a requirement of a coating peening zone, obtain data of a plurality of slice layers, and preset an additive forming trajectory and a coating peening trajectory according to the data of the slice layers.
S2: Enable an additive forming device 7 to use a rapid prototyping method such as a laser arm or an electric arc to form a plurality of layers of the part 5 to be formed on a substrate 2 layer by layer according to the preset additive forming trajectory.
S3: Enable an LACS device 9 to perform coating peening treatment on inner and outer surfaces 6 of the part to be formed according to the preset coating peening trajectory. Specifically, during the coating process, an LACS gun needs to form a certain angle with a normal vector of a coated surface to ensure that the LACS gun does not interfere with the part 5 to be formed.
S4: Repeat S2 and S3 several times until the processing and manufacturing of the part is completed.

(13) Further, in the forming process, the size, surface accuracy and density of the part 5 to be formed are detected in real time. When they fail to meet the preset requirements, the micro-rolling device 4 or the milling and grinding compound device 3 performs finish machining on the part 5 to be formed until the size and surface accuracy requirements of the part or mold are met.

(14) The hybrid forming system and method are applicable to the manufacturing of various types of parts.

(15) (1) The system can be used to coat copper or copper alloy on the surface of a high-strength steel part to enhance the surface lubrication and wear resistance of the part, so as to meet the requirements of the aerospace field for integrity, light weight, strength and stability of engines and other parts.
(2) The system is particularly suitable for the coating of functionally gradient materials (FGMs) and high melting point materials. It can be used to coat ceramic or ceramic metal materials on the surface of metal parts to produce metal parts with a gradient functional ceramic coating. Ceramic materials have the advantages of high melting point, wear resistance and corrosion resistance, but they are brittle and difficult to process, which makes them difficult to be used in the manufacture of high-performance materials. The different properties of ceramics from metals make them difficult to bond closely with metals. The poor physical compatibility of ceramic metal materials with metals makes them difficult to closely bond with metals.

(16) It is easy for those skilled in the art to understand that the above described are only the preferred examples of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should fall within the protection scope of the present invention.