1. Introduction
With the rapid development of consumer electronic products, the requirements for materials and manufacturing processes are increasing. Squeeze casting, as an efficient metal forming technology, has been widely used in the consumer electronics field. However, the traditional squeeze casting process still has many problems, such as unstable mechanical properties and difficult control of surface quality. Therefore, it is necessary to optimize and innovate the squeeze casting process to improve product quality, reduce production costs, and promote the sustainable development of the industry.
2. Current Situation of Squeeze Casting Process in Consumer Electronic Products
2.1 Application and Requirements
The rapid iteration and upgrading of consumer electronic products put forward higher requirements for the manufacturing process. Squeeze casting is widely used in the consumer electronics field due to its high efficiency, high precision, and low cost. It is suitable for the production of complex shape, thin-walled, and high-strength light alloy parts, which meets the development needs of consumer electronic products for lightweight, miniaturization, and high performance.
2.2 Existing Problems
- Internal Defects: Castings are prone to internal defects such as shrinkage holes and cracks, which affect the mechanical properties and reliability of the product.
- Surface Quality: The surface quality is difficult to control, and phenomena such as roughness and peeling often occur, affecting the appearance and feel of the product.
- Mold Wear: The mold wears seriously and has a short service life, increasing the production cost.
3. Key Factor Analysis for Optimization of Squeeze Casting Process
3.1 Influence of Casting Pressure on Product Performance
Casting pressure is one of the key process parameters affecting product performance. The level of casting pressure directly determines the filling speed and compaction degree of the metal melt in the cavity, thereby affecting the internal structure and defect distribution of the casting. If the casting pressure is too low, the filling ability of the metal melt is insufficient, resulting in defects such as insufficient pouring and cold shut, which seriously weaken the mechanical properties and reliability of the product. On the other hand, if the casting pressure is too high, it may cause mold deformation, resulting in product size out of tolerance, and even surface defects such as flash and burr, affecting the accuracy and appearance quality of the product.
| Casting Pressure | Effect on Product |
|---|---|
| Low | Insufficient filling, internal defects, weakened mechanical properties |
| High | Mold deformation, size out of tolerance, surface defects |
3.2 Influence of Mold Temperature on Surface Quality
Mold temperature is another important process parameter affecting the surface quality of squeeze casting products. The temperature and distribution of the mold directly affect the filling behavior and solidification process of the metal melt in the cavity, thereby affecting the surface quality and defect situation of the casting. When the mold temperature is too low, the fluidity of the metal melt in the cavity decreases, resulting in filling defects such as cold shut and wrinkles, and the product surface is rough and the appearance is poor. When the mold temperature is too high, the solidification time of the metal melt is prolonged, resulting in metallurgical defects such as oxidation and sticking to the mold on the casting surface, affecting the surface quality and subsequent processing performance of the product.
| Mold Temperature | Effect on Surface Quality |
|---|---|
| Low | Reduced fluidity, filling defects, rough surface |
| High | Prolonged solidification time, metallurgical defects |
3.3 Influence of Alloy Composition on Mechanical Properties
Alloy composition is a material factor that determines the mechanical properties of squeeze casting products. Different alloy elements have different effects on the strength, hardness, toughness, and wear resistance of the casting. For example, adding silicon element to aluminum alloy can precipitate hard primary silicon phase, improving the wear resistance and high-temperature strength of the casting, but excessive silicon will reduce the plasticity and toughness of the casting. Adding magnesium element can form precipitation strengthening phase, improving the plasticity and corrosion resistance of the casting, but excessive magnesium content is prone to cause hot cracks. Adding copper element can significantly enhance the strength and hardness of the casting through solid solution strengthening and precipitation strengthening, but excessive copper content will lead to a decrease in the toughness and processing performance of the casting.
| Alloy Element | Effect on Mechanical Properties |
|---|---|
| Silicon | Increases wear resistance and high-temperature strength, reduces plasticity and toughness at high content |
| Magnesium | Improves plasticity and corrosion resistance, may cause hot cracks at high content |
| Copper | Increases strength and hardness, reduces toughness and processing performance at high content |
4. Optimization of Squeeze Casting Process Based on Orthogonal Experiment
4.1 Orthogonal Experiment Design
Orthogonal experiment design is an efficient multi-factor experiment design method widely used in the optimization of squeeze casting process. By orthogonal experiment, the influence of various process parameters on the casting quality can be comprehensively investigated with the least number of experiments, and the best parameter combination can be selected.
| Trial Number | Factor A: Casting Pressure (MPa) | Factor B: Filling Speed (m/s) | Factor C: Mold Temperature (°C) | Factor D: Alloy Composition (%) |
|---|---|---|---|---|
| 1 | 60 | 30 | 180 | 5 |
| 2 | 60 | 40 | 200 | 10 |
| 3 | 60 | 50 | 220 | 15 |
| 4 | 80 | 30 | 200 | 15 |
| 5 | 80 | 40 | 220 | 5 |
| 6 | 80 | 50 | 180 | 10 |
| 7 | 100 | 30 | 220 | 10 |
| 8 | 100 | 40 | 180 | 15 |
| 9 | 100 | 50 | 200 | 5 |
4.2 Analysis of Experimental Results and Optimization of Process Parameters
- Statistical Analysis: Calculate statistical quantities such as mean, variance, and signal-to-noise ratio of each quality evaluation index to evaluate the discreteness and robustness of the experimental results.
- Main Effect and Interaction Analysis: Draw the main effect diagram and interaction diagram of each process parameter to analyze the influence trend and significance of each parameter on the casting quality. Determine the optimal level of each parameter and optimize the parameter combination scheme.
- Comprehensive Consideration: Considering factors such as production efficiency, cost, and energy consumption, balance product quality and production benefits, and select the best parameter combination scheme.
| Variance Source | Sum of Squares | Degrees of Freedom | Mean Square | F Ratio | P Value | Significance |
|---|---|---|---|---|---|---|
| Factor A | 1.2500 | 2 | 0.6250 | 0.0250 | 0.0016 | ** |
| Factor B | 0.1667 | 2 | 0.0833 | 3.3333 | 0.1250 | |
| Factor C | 0.7500 | 2 | 0.3750 | 15.0000 | 0.0067 | * |
| Factor D | 0.0167 | 2 | 0.0083 | 0.3333 | 0.7321 | |
| Error | 0.1000 | 4 | 0.0250 | |||
| Total | 2.2833 | 12 |
4.3 Establishment of Process Parameter Database and Knowledge Base
Summarize the optimization experience and laws, and establish a process parameter database and knowledge base to provide data support and decision-making basis for subsequent process design and quality control.
5. Finite Element Simulation and Verification of Optimized Process
5.1 Establishment of Finite Element Model
The finite element model is established to reveal the evolution laws of temperature field, flow field, and stress field during the casting process, predict the forming defects and mechanical properties of the casting, and guide the optimization design of process parameters.
5.2 Analysis and Discussion of Simulation Results
- Filling Process Analysis: Analyze the filling process of the casting, evaluate the rationality of the filling process, and predict the distribution of defects such as shrinkage holes and porosity.
- Solidification Process Analysis: Analyze the temperature field evolution during the solidification process of the casting, predict the tissue evolution and defects of the casting.
- Stress Field Analysis: Evaluate the residual stress level and cracking tendency of the casting, and optimize the heat treatment process of the casting.
- Mechanical Property Prediction: Predict the mechanical properties of the casting, evaluate the strength, stiffness, and reliability of the casting.
5.3 Experimental Verification
Conduct experimental research to verify the effectiveness and reliability of the optimized process. Evaluate the improvement of casting quality and performance, and establish a quantitative correlation model between process parameters and casting quality and performance.
6. Application of Optimized Process in Consumer Electronic Products
6.1 Application Case 1: Notebook Computer Shell
The notebook computer shell is a typical part with high requirements for lightweight, high strength, and appearance quality in consumer electronic products. By using the optimized squeeze casting process, a high-strength, thin-walled, and beautiful integrated aluminum alloy shell can be produced, which improves the performance and quality of the notebook computer.
| Performance Index | Improvement Before and After Optimization |
|---|---|
| Strength | Increased by more than 30% |
| Wall Thickness | Reduced by more than 20% |
| Surface Roughness | Reduced by more than 50% |
6.2 Application Case 2: Smartphone Middle Frame
The smartphone middle frame is a key structural part that connects various components of the phone, with extremely high requirements for strength, toughness, and precision. The optimized squeeze casting process can realize the rapid, low-cost, and high-quality production of the smartphone middle frame, promoting the lightweight and high-performance development of the smartphone.
| Performance Index | Improvement Before and After Optimization |
|---|---|
| Size Tolerance | Reached ±0.05mm |
| Positioning Error | Less than 0.1mm |
| Strength | Increased by more than 50% |
7. Conclusion
The optimized squeeze casting process proposed in this study can significantly improve the mechanical properties and surface quality of consumer electronic products, and has good industrial application prospects. Through finite element simulation and experimental verification, the feasibility and effectiveness of the optimization scheme are proved. In the future, it is necessary to further explore the application of new materials and new processes in the squeeze casting of consumer electronic products to meet the growing performance requirements and environmental protection requirements. At the same time, strengthen industry-university-research collaborative innovation to promote the sustainable development of squeeze casting technology.
