In the main and auxiliary mechanism of locomotive, the forging of the main and auxiliary connecting rod is the key component, and its material selection and performance optimization are very important to the performance and reliability of the engine. This paper will discuss the material selection principle, common materials and performance optimization method of main and auxiliary link forging.
Material selection principle
Strength and toughness: The main and auxiliary connecting rod forgings need to withstand higher pressure and impact force during the working process, so materials with higher strength and toughness should be selected.
Corrosion resistance: the engine working environment is harsh, high temperature, high humidity, sulfur and other gases, so the material should have good corrosion resistance.
Machinability: The material should have good malleability, machinability and weldability, which is easy to process and manufacture.
Economy: Under the premise of meeting the performance requirements, materials with lower cost should be selected as far as possible to improve the market competitiveness of the product.
Common materials
Steel material: Steel material because of its high strength, good toughness, strong corrosion resistance and other characteristics, widely used in the production of main and auxiliary connecting rod forging. Commonly used steel materials include carbon steel, alloy steel and so on.
Aluminum alloy material: Aluminum alloy material has the advantages of light weight, good corrosion resistance, good thermal conductivity, etc., which is suitable for the main and auxiliary connecting rod forging with high weight requirements.
Copper alloy material: Copper alloy has excellent thermal conductivity, corrosion resistance and machining performance, suitable for the manufacture of high heat transfer performance requirements of the main and auxiliary connecting rod forgings.
Performance optimization method
Alloying: By adding alloying elements, improve the mechanical properties, corrosion resistance and processing properties of materials. For example, adding elements such as chromium and nickel to steel can improve its corrosion resistance.
Heat treatment: By controlling the heating, insulation and cooling process, the internal organizational structure of the material is changed to achieve the required mechanical and physical properties.
Surface treatment: improve the wear resistance, corrosion resistance and fatigue resistance of the material through surface coating, carburizing hardening and other processes.
Optimization of processing technology: Reasonable processing technology can reduce the residual stress inside the material, reduce the generation of cracks, and improve the reliability of the material.
Structural design optimization: Reasonable structural design can reduce stress concentration and improve the bearing capacity of materials. In addition, the stiffness and stability of forgings can be improved by strengthening the design of key parts.
Application of new technology and new technology: The use of advanced smelting, casting and processing technology, such as vacuum melting, precision casting, CNC machining, etc., can improve the purity, density and processing accuracy of materials, so as to optimize the performance of forgings.
Material composite: Using material composite technology, the advantages of different materials can be combined to obtain composite materials with excellent properties. For example, high-strength steel is combined with wear-resistant copper alloys to improve the strength and wear resistance of connecting rods.
Finite element analysis (FEA) : Through the establishment of finite element model, the stress analysis, fatigue analysis and optimization design of forging are carried out to improve its structural design and material selection.
Test and verification: Through practical application and test verification, the performance of the forging is evaluated and optimized. According to the test results, the material composition, heat treatment process and other parameters are adjusted to achieve the best performance.
To sum up, the material selection and performance optimization of the main and auxiliary connecting rod forging is a systematic project, which requires comprehensive consideration of material performance requirements, process feasibility, economy and other factors. Through continuous exploration and practice, we can continuously improve the performance level of the main and auxiliary connecting rod forging, and provide a strong guarantee for the efficient and reliable operation of the engine.
