Multi-metal gradient structure repairing method for large die-casting die
The combination of powder metallurgy and gel condensate repair agent solves the complexity of the multi -metallic gradient structure repair of large -scale die -casting molds, achieves efficient repair effects, and ensures the strength and corrosion resistance of the repair site and the mother material.
Patent Information
- Application Number
- CN202411544413.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-31
- Publication Date
- 2025-01-21
AI Technical Summary
Due to the long-term high temperature and high pressure, large die-casting molds may suffer from wear, cracks and other damage. The existing repair methods are complex and difficult to effectively repair the multi-metal gradient structure of the mold.
Powder metallurgy and gel condensate repair agent are used for mixed preparation, and a dense repair layer is formed by coating and sintering to ensure the metallurgical binding intensity between the repair site and the mother material.
It achieves effective repair of the multi-metal gradient structure of large die-casting molds, ensures good chemical and mechanical compatibility between the repair layer and the base material, and improves the strength and corrosion resistance of the repaired part.
Smart Images
Figure CN119328146A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of die-casting mold repairing, in particular to a multi-metal gradient structure repairing method for a large die-casting mold. Background Art
[0002] Large die-casting molds may be damaged by wear, cracks, etc. due to long-term exposure to high temperature and high pressure. Repairing these molds usually involves complex processes and needs to consider the gradient structural characteristics of the mold, that is, different areas of the mold may use different metal materials to adapt to different working conditions. Summary of the invention
[0003] The purpose of the present invention is to provide a method for repairing a multi-metal gradient structure of a large die-casting mold, so as to solve the problem of repairing a multi-metal gradient structure in a large die-casting mold.
[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: A method for repairing a multi-metal gradient structure of a large die-casting mold includes the following steps: S1. Mixed powder: dissolve the Zr-containing low melting point powder A and the multi-principal alloy powder B in a solvent, and perform ball milling under a protective atmosphere to obtain a uniform mixed powder; S2. Preparing a bonding fluid: mixing appropriate amounts of ethanol, propanol, polyvinyl pyrrolidone, polyacrylamide and a polymer-based adhesive to obtain a bonding fluid; S3, preparing a gelled repairing agent: adding the obtained mixed powder into a bonding fluid and stirring evenly to obtain a gelled repairing agent having fluidity and bonding properties; S4, applying a repairing agent: applying the obtained repairing agent to the defect to be repaired of the high-temperature alloy blade; S5, curing and sintering: placing the mold coated with the repairing agent in a vacuum furnace for heat treatment, placing it in a hot pressing furnace, heating it at a heating rate of 5 to 10°C / min, degreasing the mold coated with the repairing agent at 400 to 600°C and a vacuum degree of ≤10-2Pa, and the degreasing holding time is 30 to 40min; then continuing to heat it at a heating rate of 15 to 25°C / min, sintering and repairing the mold coated with the repairing agent after degreasing at 1150 to 1250°C and a vacuum degree of ≤10-2Pa, and the sintering holding time is 240 to 330min, and cooling it with the furnace to form a metallurgical bond between the repair layer and the parent material; S6. Post-processing: Grinding, polishing and other operations are performed on the metallurgical bonding gaps to restore dimensional accuracy and surface quality.
[0005] In the above description, as a further solution, the Zr-containing low melting point powder A includes stainless steel powder, nickel-based alloy powder, and cobalt-based alloy powder, and the multi-principal alloy powder B includes copper powder and aluminum powder.
[0006] In the above description, as a further embodiment, the polymer-based adhesive includes any one of thermoplastic resins, thermosetting polymers and rubber esters.
[0007] In the above description, as a further solution, the thermoplastic resin includes any one of polyvinyl alcohol, polytetrafluoroethylene, and polyethylene.
[0008] In the above description, as a further solution, the thermosetting polymer includes any one of phenolic resin, epoxy resin and polyimide resin.
[0009] In the above description, as a further embodiment, the rubber ester includes any one of nitrile rubber and polyisoprene rubber.
[0010] The beneficial effects produced by the present invention are as follows: The multi-metal gradient structure repair method of a large die-casting mold of the present application is prepared by mixing powder metallurgy with a gelled repair agent. The repair material can be filled into the damaged part of the mold in powder form and a dense repair layer is formed by sintering. The Zr low-melting point powder A and the powder B of the multi-principal alloy have good chemical and mechanical compatibility with the base material of the die-casting mold to ensure the metallurgical bonding strength between the repair part and the base material. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is a flow chart of the steps of the multi-metal gradient structure repair method for a large die-casting mold according to the present invention. DETAILED DESCRIPTION
[0012] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with the embodiments and drawings, and the contents mentioned in the embodiments are not intended to limit the present invention. The present invention is described in detail below in conjunction with the drawings.
[0013] Embodiment 1: See also Figure 1 The multi-metal gradient structure repair method of a large die-casting mold specifically implemented includes the following steps: S1. Mixed powder: dissolve a Zr-containing low melting point powder A composed of stainless steel powder, nickel-based alloy powder and cobalt-based alloy powder and a multi-principal alloy powder B composed of copper powder and aluminum powder in a solvent, and perform ball milling under a protective atmosphere to obtain a uniform mixed powder; S2. Prepare bonding fluid: mix appropriate amounts of ethanol, propanol, polyvinyl pyrrolidone, polyacrylamide and polyvinyl alcohol to obtain bonding fluid; S3, preparing a gelled repairing agent: adding the obtained mixed powder into a bonding fluid and stirring evenly to obtain a gelled repairing agent having fluidity and bonding properties; S4, applying a repairing agent: applying the obtained repairing agent to the defect to be repaired of the high-temperature alloy blade; S5, curing and sintering: placing the mold coated with the repairing agent in a vacuum furnace for heat treatment, placing it in a hot pressing furnace, heating it at a heating rate of 5 to 10°C / min, degreasing the mold coated with the repairing agent at 400 to 600°C and a vacuum degree of ≤10-2Pa, and the degreasing holding time is 30 to 40min; then continuing to heat it at a heating rate of 15 to 25°C / min, sintering and repairing the degreased mold coated with the repairing agent at 1150 to 1250°C and a vacuum degree of ≤10-2Pa, and the sintering holding time is 240 to 330min, cooling it with the furnace, so that the repair layer forms a metallurgical bond with the parent material, and the gelled repairing agent containing polyvinyl alcohol can be quickly hardened when preheating and cooling before sintering, which is conducive to maintaining the structural stability of the defect and preventing deformation during curing and sintering; S6. Post-processing: Heat treatment, grinding, polishing and other operations are performed on the metallurgical bonding gaps to restore dimensional accuracy and surface quality.
[0014] Embodiment 2: A method for repairing a multi-metal gradient structure of a large die-casting mold includes the following steps: S1. Mixed powder: dissolve a Zr-containing low melting point powder A composed of stainless steel powder, nickel-based alloy powder and cobalt-based alloy powder and a multi-principal alloy powder B composed of copper powder and aluminum powder in a solvent, and perform ball milling under a protective atmosphere to obtain a uniform mixed powder; S2. Prepare bonding fluid: mix appropriate amounts of ethanol, propanol, polyvinyl pyrrolidone, polyacrylamide and polyimide resin to obtain bonding fluid; S3, preparing a gelled repairing agent: adding the obtained mixed powder into a bonding fluid and stirring evenly to obtain a gelled repairing agent having fluidity and bonding properties; S4, applying a repairing agent: applying the obtained repairing agent to the defect to be repaired of the high-temperature alloy blade; S5, curing and sintering: placing the mold coated with the repairing agent in a vacuum furnace for heat treatment, placing it in a hot pressing furnace, heating it at a heating rate of 5 to 10°C / min, degreasing the mold coated with the repairing agent at 400 to 600°C and a vacuum degree of ≤10-2Pa, and the degreasing holding time is 30 to 40min; then continuing to heat up at a heating rate of 15 to 25°C / min, sintering and repairing the degreased mold coated with the repairing agent at 1150 to 1250°C and a vacuum degree of ≤10-2Pa, and the sintering holding time is 240 to 330min, cooling with the furnace, so that the repair layer and the parent material form a metallurgical bond, and the gelled repairing agent containing the polyimide resin can form a strong three-dimensional network structure after curing and sintering, which specifically improves the corrosion resistance of the junction between the repair layer and the parent material; S6. Post-processing: Heat treatment, grinding, polishing and other operations are performed on the metallurgical bonding gaps to restore dimensional accuracy and surface quality.
[0015] The method adopts powder metallurgy and gelled repair agent for mixed preparation, and the repair material can be filled into the damaged part of the mold in powder form, and a dense repair layer is formed by sintering, wherein the Zr low melting point powder A and the powder B of the multi-principal alloy have good chemical and mechanical compatibility with the base material of the die-casting mold to ensure the metallurgical bonding strength between the repair part and the base material.
[0016] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention is disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments according to the technology of the present invention are within the scope of the technical solution of the present invention without departing from the content of the technical solution of the present invention.
Claims
1. A method for repairing a multi-metal gradient structure of a large die-casting mold, characterized in that: The following steps are involved: S1. Mixed powder: dissolve the Zr-containing low melting point powder A and the multi-principal alloy powder B in a solvent, and perform ball milling under a protective atmosphere to obtain a uniform mixed powder; S2. Preparing a bonding fluid: mixing appropriate amounts of ethanol, propanol, polyvinyl pyrrolidone, polyacrylamide and a polymer-based adhesive to obtain a bonding fluid; S3, preparing a gelled repairing agent: adding the obtained mixed powder to a bonding fluid and stirring evenly to obtain a gelled repairing agent having fluidity and bonding properties; S4, applying a repairing agent: applying the obtained repairing agent to the defect to be repaired of the high-temperature alloy blade; S5, curing and sintering: placing the mold coated with the repair agent in a vacuum furnace for heat treatment, and sintering at a high temperature to form a metallurgical bond between the repair layer and the base material; S6. Post-processing: Heat treatment, grinding, polishing and other operations are performed on the metallurgical bonding gaps to restore dimensional accuracy and surface quality.
2. The method for repairing a multi-metal gradient structure of a large die-casting mold according to claim 1, characterized in that: The Zr-containing low melting point powder A includes stainless steel powder, nickel-based alloy powder, and cobalt-based alloy powder, and the multi-principal alloy powder B includes copper powder and aluminum powder.
3. The method for repairing a multi-metal gradient structure of a large die-casting mold according to claim 1, characterized in that: The polymer-based adhesive includes any one of thermoplastic resins, thermosetting polymers and rubber resins.
4. The method for repairing a multi-metal gradient structure of a large die-casting mold according to claim 3, characterized in that: The thermoplastic resin includes any one of polyvinyl alcohol, polytetrafluoroethylene and polyethylene.
5. The method for repairing a multi-metal gradient structure of a large die-casting mold according to claim 3, characterized in that: The thermosetting polymer includes any one of phenolic resin, epoxy resin and polyimide resin.
6. The method for repairing a multi-metal gradient structure of a large die-casting mold according to claim 3, characterized in that: The rubber esters include any one of nitrile rubber and polyisoprene rubber.