CN104388849A - Quick molding method of metal-matrix composite part - Google Patents

Abstract

The invention discloses a rapid prototyping method for metal matrix composite parts. In this method, the three-dimensional CAD model of the part is layered along the Z direction, the fibers are laid layer by layer, and laser fusion is carried out following the fibers. After one layer of printing is completed, the thickness of one layer is reduced and printed layer by layer until the part is manufactured. The forming method has high flexibility, can form parts with complex shapes, and is suitable for the rapid preparation of complex gradient composite materials.

Description

A Rapid Prototyping Method for Metal Matrix Composite Parts

technical field

The invention belongs to the field of manufacturing technology, in particular to a rapid prototyping method for continuous fiber reinforced metal matrix composite parts.

Background technique

Continuous fiber-reinforced metal matrix composites are made of high-strength, high-modulus, low-density boron fibers, alumina fibers, silicon carbide fibers, carbon fibers, etc. as reinforcements, combined with the corresponding metal matrix. Compared with short-fiber reinforced continuous fiber-reinforced metal matrix composites, continuous fiber-reinforced composites have greatly improved mechanical strength, compressive strength, and fatigue resistance, so they have wider applications in advanced weapons, aerospace and other fields prospect. The traditional preparation methods of continuous fiber reinforced metal matrix composites can be divided into two categories: solid state method (FFF) and liquid state method. The solid-state method is to mix and arrange metal foil or metal powder and fibers together in a certain content, distribution, and direction according to the design requirements, and then pressurize and heat to bond the metal matrix and reinforcement together to form a composite material. Preparation. The process of this method is complex, especially the manufacture of the matrix alloy foil, which seriously limits its wide application. The liquid method is to prefabricate the fiber-reinforced phase first, then pour the matrix melt into it, and make it infiltrate into the fiber gap under pressure or negative pressure to achieve the purpose of compounding. This method is only used for materials with lower melting points, such as magnesium, aluminum and zinc alloys, and is less used for titanium-based and nickel-based composite materials with high melting points.

Rapid prototyping (Rapid Prototyping) technology emerged in the 1990s. It is a part prototype manufacturing technology that integrates computer technology, laser processing technology, and new material technology. Different from the traditional method of removing material to manufacture parts, rapid prototyping technology relies on CAD software to establish a three-dimensional solid model in the calculation set, and discretize it into a series of plane geometric information, by controlling the scanning direction of heat sources such as laser beams or electron beams And speed, using methods such as bonding, sintering, polymerization or chemical and reaction to selectively process raw materials layer by layer, so as to quickly accumulate a solid model additive manufacturing method. Currently commonly used rapid prototyping methods are: stereolithography (SLA), layered solid manufacturing (LOM), selective laser sintering (SLS), three-dimensional printing (3DP) and fused deposition manufacturing (FDM). These methods generally use photosensitive resin, plastic film, wax, nylon, metal or ceramic powder as forming materials, so only metal or non-metal parts of corresponding materials can be manufactured. For composite materials with strong market demand and broad application prospects, especially the rapid manufacturing of continuous fiber-reinforced metal matrix composites, the above methods are difficult to achieve.

Laser cladding technology is a new laser processing technology that emerged in the 1970s. It uses laser irradiation to rapidly heat and melt alloy powder or ceramic powder and the surface of the substrate, and then cools to form a very low dilution rate. Surface coating of materials that are metallurgically bonded A method of surface strengthening. Due to the fast cooling rate of the laser cladding layer, it is easy to obtain a fine-grained structure or a new phase that cannot be obtained in an equilibrium state, such as an unstable phase and an amorphous state, so it has excellent wear resistance, corrosion resistance, heat resistance, and oxidation resistance. and electrical characteristics.

Contents of the invention

The purpose of the present invention is to provide a rapid manufacturing method of continuous fiber reinforced metal matrix composite parts with high precision, good performance and high degree of automation.

The rapid manufacturing method of continuous fiber reinforced metal matrix composite parts of the present invention comprises the following steps:

A. Use 3D CAD modeling software to establish 3D solid models of parts;

B. Discretize the established model in the Z direction;

C. Carry out fiber laying path planning for the ply;

D. Lay fibers continuously according to the planned path of the ply, and perform laser welding following the laid fibers;

E. After the layer welding is completed, the workbench is lowered to a working height;

F. Repeat steps D and E until the part is finished.

The fiber laying method is as follows: the fiber is led out by the wire guide nozzle and moved under the drive of the wire guide nozzle.

The laser cladding method is as follows, following the laid fibers, spraying metal powder on the path where the fibers have been laid, and using laser radiation to melt the powder. The sprayed metal powder can be aluminum and aluminum alloy powder, magnesium and magnesium alloy powder, titanium and titanium alloy powder, nickel and nickel alloy powder.

When laser cladding the placed fibers, it is judged whether the ply is the first layer. If the ply is the first layer, it is not necessary to lay the fibers, and only laser cladding is performed. After the cladding is completed, the cladding layer is removed according to the layer information.

In order to achieve a better welding effect, the following process conditions are used in the laser welding: laser power 200-3000W, spot diameter 1-8mm, scanning speed 10-100mm/s, powder feeding amount 5-25g/min .

The beneficial effects produced by the rapid prototyping method of continuous fiber reinforced metal matrix composite parts of the present invention are:

(1) On the basis of the computer three-dimensional solid model, two-dimensional plane processing is used to directly form parts of continuous fiber-reinforced metal matrix composite materials, which reduces the manufacturing difficulty and the requirements for high-dimensional manufacturing of the numerical control system;

(2) Fiber laying and laser cladding are carried out simultaneously, the forming speed is fast, and it is easy to realize the rapid prototyping of continuous fiber reinforced metal matrix composites;

(3) Through the adjustment of laser power, not only the preparation of magnesium, aluminum and zinc-based composite materials with low melting point can be realized, but also the rapid prototyping of high-melting point metals such as titanium-based and nickel-based composite materials can be realized;

(4) The use of powder as the matrix material can greatly increase the flexibility of material design, making it possible to rapidly prepare complex gradient composite materials;

(5) The heat input of laser cladding is small, and the deformation of the cladding layer is small, so it is conducive to the rapid manufacture of large-scale metal matrix composites.

Description of drawings

Fig. 1 is the rapid manufacturing process flowchart of continuous fiber reinforced metal matrix composite material of the present invention;

Fig. 2 is the manufacturing schematic diagram of continuous fiber reinforced metal matrix composite material of the present invention;

Fig. 3 is the schematic diagram of the cuboid part of carbon fiber reinforced aluminum matrix composite material manufactured in embodiment 1;

Fig. 4 is the schematic diagram of the carbon fiber reinforced titanium alloy tubular part manufactured in embodiment 1;

reference sign

1-Working table 2-Fiber 3-Wire guide nozzle 4-Cladding head 5-Metal powder 6-Laser head 7-Milling cutter

8 - Metal matrix composites.

Detailed ways

The present invention will be described in detail through two examples below, but not as a limitation of the present invention.

Embodiment 1: Utilize the present invention to manufacture a 40×40×10mm carbon fiber reinforced aluminum matrix composite cuboid part;

(1) Use a computer to build a cube model of 40×40×10mm;

(2) The above model is discretized in the Z direction, that is, the cube model is divided into a layered model with a thickness of 1mm, a total of 10 layers, and each layer is a square of 40×40mm;

(3) Select fiber with matching thickness and matching laser cladding process according to the thickness of the layer;

(4) Determine the laying and laser cladding path according to the ply model;

(5) Determine whether the layer is the first layer, if so, spray aluminum alloy powder along the planned path, and achieve welding under laser irradiation, otherwise proceed to step (6);

(6) Use a milling cutter to remove the part other than 1mm in the thickness direction of the welded sheet;

(7) The fiber is guided by the wire guide to move along the planned path, and the cladding head and the laser head follow the wire guide and move behind it in the form of coaxial powder feeding;

(8) After the layer processing is completed, move the workbench down by 1mm;

(9) Determine whether all layers are processed, if not, repeat steps (6)~(8) until all layers are processed.

Embodiment two: Utilize the present invention to manufacture a carbon fiber reinforced titanium alloy tubular part with an inner diameter of 36mm, an outer diameter of 40mm, and a height of 10mm;

(1) Use a computer to build a tubular model with an inner diameter of 36mm, an outer diameter of 40mm, and a height of 10mm;

(2) The above model is discretized in the Z direction, that is, the cube model is divided into a layered model with a thickness of 2mm, a total of 5 layers, each layer is a ring with an inner diameter of 36mm and an outer diameter of 40mm;

(3) Determine the fiber placement and laser cladding path according to the ply model;

(4) Select fiber with matching thickness and matching laser cladding process according to the thickness of the layer;

(5) Determine whether the layer is the first layer, if so, spray titanium alloy powder along the planned path, and achieve cladding under laser irradiation, otherwise proceed to step (6);

(6) Use a milling cutter to remove the part other than 2mm in the thickness direction of the welded sheet;

(7) The fiber is guided by the guide nozzle to move along the planned path, and the cladding head and laser head follow the guide nozzle and move behind it in the form of side-axis powder feeding;

(8) After the layer processing is completed, move the workbench down by 2mm;

(9) Determine whether all layers are processed, if not, repeat steps (6)~(8) until all layers are processed.

The above description of the present invention and its embodiments is illustrative, not restrictive. Therefore, if those of ordinary skill in the art are inspired by it and carry out other embodiments without departing from the inventive concept of the present invention, all should belong to the protection scope of the present invention.

Claims (8)

1. A method for rapid prototyping of metal matrix composite parts, characterized in that, comprising the steps: A. Use 3D CAD modeling software to establish 3D solid models of parts; B. Discretize the established model in the Z direction; C. Plan the fiber laying path for the layer; D. Continuously lay fibers according to the planned path of the ply, and perform laser welding following the placed fibers; E. After the lamination is completed, the workbench is lowered to a working height; F. Repeat steps D and E until the part is finished. 2. The method for rapid prototyping of continuous fiber-reinforced metal matrix composite parts according to claim 1, wherein said fibers include boron fibers, alumina fibers, silicon carbide fibers, and carbon fibers. 3. The method for rapid prototyping of continuous fiber-reinforced metal matrix composite parts according to claim 1, characterized in that the laying method of the fibers is that the fibers are led out by the guide nozzle, and driven by the guide nozzle Move down. 4. The method for rapid prototyping of continuous fiber-reinforced metal matrix composite parts according to claim 1, characterized in that, the method of laser cladding is, following the laid fibers, on the surface where the fibers have been laid The path sprays metal powder and uses laser irradiation to melt the powder. 5. The laser cladding method according to claim 4, characterized in that, the metal powder spraying method is coaxial powder feeding or side-axis powder feeding. 6. According to claim 4, spraying metal powder on its laid path, it is characterized in that, described metal powder is aluminum and aluminum alloy powder, magnesium and magnesium alloy powder, titanium and titanium alloy powder, nickel and Nickel alloy powder. 7. The method for rapid prototyping of continuous fiber-reinforced metal matrix composite parts according to claim 1, characterized in that, if the ply is the first layer, it is not necessary to lay fibers, only laser welding is performed, and the welding After completion, layer removal processing is performed on the cladding layer according to the layer information. 8. The method for rapid prototyping of continuous fiber reinforced metal matrix composite parts according to claim 1, characterized in that the process conditions used in the laser cladding are: laser power 200-3000W, spot diameter 1-8mm , scanning speed 10-100mm/s, powder feeding volume 5-25g/min.