CN-121973533-A - Layered heterogeneous metal hot-pressing composite forming method

Abstract

The invention discloses a hot-pressing composite forming method for layered heterogeneous metal, and belongs to the field of layered metal material manufacturing. The method comprises the steps of providing at least two metal components, wherein a first metal component with the highest melting point is a metal block, the rest components are metal powder, and the melting point is reduced from a base block to a subsequent powder layer by layer. And then loading the metal block and the powder into a mould in a layered structure, vacuumizing or introducing protective atmosphere, and performing two-stage hot pressing compounding, wherein the first stage adopts medium-temperature high-pressure compaction to realize rapid densification and interfacial pre-combination of the powder, and the second stage adopts high-temperature low-pressure to promote the metallurgical diffusion of the interface and actively relax the thermal stress of the interface. By repeatedly superposing the powder-solid composite units as a matrix, a multilayer composite material with a preset layer number can be prepared layer by layer. The invention effectively solves the problems of poor interface bonding, more brittle phases, high residual stress, poor plate shape and the like in the traditional method, and has the advantages of safety, high efficiency, high yield, flexible thickness design, excellent comprehensive performance and the like.

Inventors

• XIONG CHENGYUE
• ZHANG XIN
• Yuan Aoming
• ZHOU YUWEI
• LI YONGBING

Assignees

• 北京机科国创轻量化科学研究院有限公司

Dates

Publication Date

20260505

Application Date

20251226

Claims (9)

1. 1. The hot-pressing composite forming method for the layered heterogeneous metal is characterized by comprising the following steps of: (1) Providing at least two metal components, wherein a first metal component with the highest melting point is a metal block, and the rest metal components are metal powder, and the melting point of the metal components is reduced from the first metal component layer by layer after the metal powder components added layer by layer; (2) Loading the metal block in the step (1) and at least one metal powder into a mold in a mutually contacted layered structure, and tightly matching the metal block with a mold cavity; (3) Vacuumizing the die cavity in the step (2) or introducing protective atmosphere to obtain a preform assembly; (4) Carrying out a two-stage hot-pressing compounding process on the preform assembly obtained in the step (3): a) The first stage, heating the preform assembly to a first temperature T 1 , and performing heat preservation and pressure maintaining at a first axial pressure P 1 , wherein T 1 meets the requirement that 0.6T m ≤ T 1 ≤ 0.75T m ,T m is the melting point of the metal powder component with the highest melting point, and P 1 is more than or equal to 50 MPa; b) The second stage, namely heating the preform assembly to a second temperature T 2 , and adjusting the pressure to a second axial pressure P 2 for heat preservation, wherein T 2 meets 0.75T m ≤ T 2 ≤ 0.9T m ,P 2 , P 2 is more than or equal to 10 MPa and less than or equal to 50 MPa, and P 2 ≤ 0.5P 1 ; Carrying out the two-stage hot-pressing compounding treatment to obtain a layered composite material; (5) And (3) taking the composite material obtained in the step (4) as a matrix block for subsequent processing, and repeating the steps (2) to (4), namely sequentially carrying out the steps of filling the matrix block and the next layer of metal powder components into a die, carrying out atmosphere treatment and carrying out two-stage hot-pressing compounding until the multilayer heterogeneous metal composite material with the preset layer number is obtained.
2. 2. The method according to claim 1, wherein in the step (2), the metal block is controlled to fit into the mold cavity, and the metal powder is filled into the assembly gap between the metal block and the mold cavity wall.
3. 3. The method of hot press compounding of layered heterogeneous metals according to claim 1, wherein in step (4), after the second stage of hot press compounding, controlled cooling is performed, and the axial pressure is gradually unloaded during the cooling.
4. 4. The method according to claim 1, wherein in the step (5), the set value of the second temperature T 2 is reduced in a gradient manner during the layer-by-layer hot press compounding of the metal powder component.
5. 5. The method of hot press composite forming of a layered heterogeneous metal according to claim 1, further comprising a step of cleaning the bonding surface of the metal block and/or drying the metal powder after the step (1) and before the step (2).
6. 6. The method for hot press composite forming of a layered heterogeneous metal according to claim 1, wherein the particle size d90 of the metal powder is not more than 100 μm.
7. 7. A layered heterogeneous metal composite material is characterized by comprising at least two metal layers which are compounded in a metallurgical bonding mode, wherein the melting points of adjacent metal layers are different.
8. 8. The layered heterogeneous metal composite of claim 7, wherein the composite has a gradient of melting points of the metal layers in the thickness direction.
9. 9. A layered heterogeneous metal composite prepared by the method of any one of claims 1 to 6.

Description

Layered heterogeneous metal hot-pressing composite forming method Technical Field The invention relates to the field of layered metal material manufacturing, in particular to a layered heterogeneous metal hot-pressing composite forming method. Background Layered heterogeneous metal composite materials (such as copper/steel, aluminum/steel, titanium/aluminum, aluminum/magnesium and the like) have great application potential in the key fields of aerospace, national defense and military industry, high-end equipment and the like by virtue of the unique function-structure integration advantages. However, due to the inherent difference of the physical characteristics and the processing technology of each component metal, the common technical problem that the interface is difficult to accurately regulate and control is generally faced by the existing preparation method, and the large-scale production and industrial application of the material are severely restricted. The traditional explosion compounding method has the production problems of large pollution, high safety risk and the like, the product is often accompanied with defects of poor plate shape, interface melting or cracking and the like, continuous stable production is difficult to realize, the traditional diffusion compounding method is generally low in combination property, long in production period and high in cost, large-scale industrial production is difficult to realize, significant residual stress is introduced at an interface by a rolling compounding method to cause the problems of warping, twisting, poor interface combination and the like of a composite plate, the surfacing compounding method is strictly limited by the metallurgical compatibility of a welding material and a matrix, a heat affected zone is large, air holes and residual stress are easy to generate, the casting compounding method can generate severe element interdiffusion at the compounding interface to easily generate various brittle and hard phases, the combination property is unstable, the hole inclusion defect is easy to generate by the stirring friction welding compounding method, the process window is narrow, the thickness of the manufactured material is limited, the process flow of the traditional powder sintering compounding method is tedious, the period is long, and the compactness of the manufactured workpiece is low. The methods of laser cladding, cold spraying, a composite process (such as laser assisted cold spraying) and the like essentially belong to the technical category of surface engineering, and the investment and maintenance cost is high although the coating bonding strength is high, the process window is narrow, and the high-thickness composite board is difficult to prepare efficiently and economically. Therefore, there is a need to develop a new technology for preparing layered heterogeneous metal composite materials, which can realize continuous and efficient production, has cost advantages, and has high interface bonding strength, less brittle hard phase, low residual stress, excellent plate shape and flexible and adjustable thickness. Disclosure of Invention The invention aims to solve the core problems of poor interface performance, difficult regulation and control of a brittle hard phase, high residual stress, poor plate shape and the like caused by mismatch of a thermal-mechanical process and the like caused by imperfect interface bonding mechanism in the preparation of the existing layered heterogeneous metal composite material, and simultaneously provides a powder-solid hot-pressing composite forming method aiming at manufacturing bottlenecks of low production efficiency, high cost, specification solidification and the like. According to the method, synchronous optimization of heterogeneous materials on microscopic interfaces and macroscopic forming quality is realized through the controllable diffusion/reaction of powder and a solid interface and the collaborative design of a two-stage hot pressing process (high medium temperature and high pressure and high temperature and low pressure), so that the technical coupling problem in the preparation of the composite material is solved by the system. The technical scheme of the invention is as follows: A layered heterogeneous metal hot-pressing composite forming method sequentially comprises the following steps: (1) Providing at least two metal components, wherein a first metal component with the highest melting point is a metal block, and the rest metal components are metal powder, and the melting point of the metal components is reduced from the first metal component layer by layer after the metal powder components added layer by layer; (2) Loading the metal block in the step (1) and at least one metal powder into a mold in a mutually contacted layered structure, and tightly matching the metal block with a mold cavity; (3) Vacuumizing the die cavity in the step (2) or introducing protective atmosphere to