Introduction: Market Background of the Latest Aluminum Die Casting Technology
The latest aluminum die casting technology is gaining attention as a means to achieve both lightweighting and high performance in automotive parts and electronic device housings. In recent years, against the backdrop of the need for lighter EVs (Electric Vehicles) and more advanced industrial equipment, the market size has been expanding at an annual rate of 5-7% (according to a survey by Daiwa Light Alloy Industry Vietnam).
On the other hand, with the increasing freedom in design, there is a rapidly growing demand for more complex shapes, thinner-walled parts, and high-precision dimensional tolerances at the ±0.05 mm level. In particular, achieving wall thicknesses as low as 0.6 mm and replicating fine fins has reached its limits with conventional casting processes alone, making the introduction of new, cutting-edge aluminum die casting technology essential.
This article, focusing on the keyword “latest aluminum die casting technology,” will explain everything from the principles and latest trends to implementation examples of the three major trends: higher precision, thinner walls, and support for complex shapes. We will first provide an overview of the market background, and then detail the specific technological elements in the subsequent chapters.
The Latest Aluminum Die Casting Technology: Higher Precision
High-Pressure Injection and High-Pressure Resistant Mold Design
The latest aluminum die casting technology involves instantaneously injecting molten aluminum at high pressures of several hundred MPa, achieving uniform filling throughout the mold cavity. This significantly reduces variations in wall thickness and solidification defects, making it possible to stably achieve high-precision tolerances of ±0.05 to ±0.1 mm. Designing molds that can withstand high pressure requires the selection of appropriate steel materials, optimization of the mold structure, and stress analysis using CAE. The wall thickness and rib placement around the cavity are determined through simulation to suppress mold deformation during injection and extend the mold’s lifespan.
Improving Mold Precision with CNC/Grinding
Processing that combines 5-axis CNC and high-precision grinding machines allows the mold cavity to be machined at the micron level (0.001 mm). By optimizing the machining path and utilizing an automatic tool wear compensation function, post-casting secondary processing is reduced, dramatically improving production yield and reproducibility during mass production.
Process Optimization Utilizing AI/CAE
By running hundreds of patterns of CAE (Computer-Aided Engineering) simulations in the initial stage, the optimal solution for mold design and injection conditions can be quickly derived. This reduces the number of prototypes, mitigating the risks of mold manufacturing costs and lead times. Furthermore, an AI-based process control system optimizes injection pressure and mold temperature in real-time and detects early signs of abnormalities. This prevents dimensional deviations and internal defects before they occur.
The Latest Aluminum Die Casting Technology: Thinner Walls
Thin-Wall Design Guidelines and Mechanical Analysis
To achieve thinner walls, it is crucial to understand the load paths acting on the product and to perform “topology optimization.” By optimizing the rib structure and fillets (rounded corners) through CAE stress analysis, it is possible to achieve defect-free thinning from 0.8 mm down to 0.6 mm. Additionally, by repeatedly conducting cooling analysis and optimizing the gate position and cooling line design, shrinkage cavities and gas entrapment in thin-walled sections are suppressed.
Application of Vacuum Die Casting and Semi-Solid Casting
In vacuum die casting, the air inside the cavity is evacuated, significantly reducing bubble defects even in thin-walled sections of 1 mm or less. There are proven results of reducing the internal defect rate by over 50% compared to conventional gravity casting. Semi-solid casting (thixocasting) turns the aluminum alloy into a slurry state, achieving both fluidity and solidification control. This suppresses shrinkage cavities in thin-walled sections and enables stable casting even for complex-shaped thin-walled parts.
Forming Fine Wall Sections with 3D Printed Molds
3D printed molds allow for the free design of internal cooling channels and fine ribs, which was difficult with conventional methods. A lattice-like cooling structure, the “conformal cooling channel,” enables rapid and uniform cooling even for 0.6 mm thin walls, reducing distortion and residual stress. By utilizing heat-resistant Maraging steel and cobalt alloys, dimensional accuracy is maintained even under high thermal cycles, achieving costs of 1 million yen or less and lead times of 2-4 weeks for small to medium lot prototypes and mass production.
The Latest Aluminum Die Casting Technology: Handling Complex Shapes
Introduction of Movable Cores and Multi-Core Structures
The latest aluminum die casting technology uses a combination of movable cores (slide cores) and multi-core structures to form undercut shapes and internal cavities in a single process. When the mold opens and closes, the slide core moves to release the undercut, enabling smooth product ejection. By combining this with a multi-core structure that synchronizes hydraulic cores and inclined pins, it is possible to handle undercuts in multiple directions and form complex concave-convex shapes without the need for post-processing.
The Latest Aluminum Die Casting Technology: Example of Gigacasting (Large-Scale Integrated Molding)
Gigacasting, a technology attracting attention in the latest aluminum die casting field, expands the size of integrally molded parts from the conventional sub-50 cm to over 1 meter. For a car’s rear underbody, about 70 parts were integrated into a single Gigacast component, reducing the assembly process by over 40%. By combining large die casting machines with a clamping force of 6,000 tf or more, high-pressure resistant molds, and precise cooling design, structural components for EVs and luxury cars can be integrated while maintaining strength, dramatically improving production efficiency.
The Latest Aluminum Die Casting Technology: High-Precision Reproduction of Pin & Fin Shapes
To reproduce fine details like thin-walled fins and pin-shaped ribs with high precision, small-diameter pin inserts and dedicated fin molds are utilized. Dividers and sprue cores that control the molten metal flow are optimally placed to homogenize the flow direction and cooling profile. This suppresses cracks and filling defects even in 0.6 mm fine fins, achieving an accuracy of ±0.05 mm. Furthermore, in coordination with 3D printed molds, continuous cooling channels are designed internally. Techniques to minimize distortion in fine shapes by controlling solidification behavior through rapid cooling are also advancing.
Success Story: Fusing High Precision, Thin Walls, and Complex Shapes with the Latest Aluminum Die Casting Technology
Overview Daiwa Light Alloy Industry Vietnam Co., Ltd. successfully achieved the integrated casting of a complex-shaped part for an EV motor rear housing, featuring both a 0.6 mm thin-walled section and fine fins. Key Technical Points
- Uniform cooling using conformal cooling channels within a 3D printed mold.
- Suppression of gas bubbles with vacuum die casting to ensure a high-quality cast surface.
- Multivariate optimization of injection conditions and mold design using AI/CAE. Results
- Achieved a dimensional tolerance of ±0.05 mm and a yield rate of 99.5%.
- Shortened the cooling cycle by 20% compared to conventional methods, significantly improving productivity.
Failure Story: Pitfalls of Applying the Latest Aluminum Die Casting Technology
Overview When Meiwa Seisakusho prototyped a 0.5 mm thin-walled connector using a graphite mold, approximately 20% of the parts had internal cracks and gas bubble defects. Main Issues & Cause Analysis
- Mold separation due to the difference in thermal expansion of the graphite mold material.
- Non-uniform placement of cooling lines caused localized solidification delays, leading to frequent shrinkage cavities and gas entrapment. Improvement Measures
- Changed the mold material to high thermal conductivity Maraging steel.
- Designed a lattice-like cooling channel with 3D printing to equalize cooling efficiency.
- Re-simulated the cooling profile with CAE to determine the optimal gate position and cooling line placement.
Sources
- Sources: What is a Slide Core in Die Casting?, Soyo Sangyo Co., Ltd. Die Casting Technology Introduction, What is Gigacasting? The Forefront of Large-Scale Aluminum Casting Technology Accelerating Manufacturing DX, Why “Gigacasting” is Causing a Major Revolution in the Automotive Industry, Die casting mold: A Detailed Guide to Die Casting Mold Tooling
Data Box: Key Indicators of the Latest Aluminum Die Casting Technology
Conclusion: Summary and Future Outlook of the Latest Aluminum Die Casting Technology
Summary of Each Technological Trend
For higher precision, stable dimensional tolerances at the ±0.05 mm level are ensured through high-pressure injection of several hundred MPa and optimal high-pressure resistant mold design, while CNC/grinding achieves micron-level mold accuracy. Furthermore, process optimization via AI/CAE simulation creates a synergistic effect, dramatically improving manufacturing yield and reproducibility. For thinner walls, defect-free molding down to a wall thickness of 0.6 mm has become possible through mechanical analysis based on topology optimization and the combined application of vacuum die casting and semi-solid casting. For handling complex shapes, the introduction of movable/multi-core structures, integrated molding with large-scale Gigacasting, and high-precision reproduction technology for pin & fin areas have consolidated conventional multi-step processes into a single step, achieving significant efficiency improvements and cost reductions.
Future Outlook and Implications for Companies
The latest aluminum die casting technology is expected to evolve further through real-time process control utilizing digital twins and improvements in the wear and heat resistance of 3D printed molds. Additionally, by integrating closed-loop recycling across the entire supply chain and establishing a comprehensive system that considers post-use recycling, it is possible to achieve quality control and cost optimization simultaneously. Companies are strongly encouraged to strategically combine these latest technologies and promptly establish an organizational structure aimed at shortening new product development cycles and reducing environmental impact.
