Best Practices for Deformation Control in Thin-Walled Die Castings

The manufacturing industry demands increasingly lightweight and high-performance mechanical components, leading to a surge in the use of thin-walled plate-like structures. However, these designs present significant challenges during manufacturing. Casting and machining operations can introduce significant deformations due to factors such as residual stresses and improper clamping. This can result in dimensional inaccuracies, reduced fatigue life, and compromised performance. This article focuses on an automotive intermediate plate as a case study to explore effective strategies for minimizing deformation in thin-walled die-castings.

The middle plate is a key part used to fix the motors on both sides in a certain automobile gearbox. It weighs about 1.2kg and is made of ADC12 die-cast aluminum alloy. The appearance is shown in Figure 1. It is a typical thin-walled plate-like part, disc-shaped, with an outer size of about φ340mm. The wall thickness of the middle connection part is 5mm. In order to make the design lightweight, a large area is hollowed out, which greatly reduces the rigidity of the part and increases the difficulty of its die-casting and processing.

Figure 1 Appearance of the middle plate

Figure 2 Schematic diagram of parts with strict precision requirements

Figure 3 Fixture for middle plate solution 2

1.Press head 2. U-axis tailstock 3. Tailstock L plate 4. Fixture bottom plate 5. Diamond pin 6. Floating support 7. Fixed support 8. Pre-positioning guide column 9. Round pin

Due to the poor rigidity of the middle plate, a small clamping torque can also produce a lever effect, causing local deformation of the workpiece, rebound after processing, and reduce the processing accuracy. Therefore, the clamping point and support point of such parts must be set point to point, and the clamping force arm should be 0 as much as possible. The action sequence is: put the workpiece in place → clamp the fixed support → float the floating support → clamp the floating support clamping point.

Figure 4 Z3-2 hole Y-axis coordinate offset fluctuation diagram

Figure 5 X/Y-axis thermal offset of the vertical machining center

Conclusion

Controlling initial blank deformation within acceptable limits is crucial for establishing a reliable reference point for subsequent machining operations. The machining allowance directly correlates with the required dimensional accuracy; higher accuracy demands smaller allowances. For thin-walled plate-like workpieces, the design and manufacturing quality of the fixture play a pivotal role in achieving precise machining results. Consistent daily maintenance of the fixture is essential. While thermal deformation of the machine tool may have minimal impact on milling flatness, it can significantly affect hole positioning accuracy. Therefore, implementing effective thermal compensation strategies is necessary.

• 

  Why Custom Aluminum Die Casting Is Ideal for Automotive Components

  In the automotive industry, precision, durability, and efficiency are paramount. The materials and manufacturing processes used directly impact the performance and longevity of automotive components. ...
• 

  Revolutionizing the Automotive Industry with Aluminum Die Casting Components

  The automotive industry has always been synonymous with innovation and technological advancements. With the constant demand for light-weight materials that ensure durability, aluminum die-casting comp...
• 

  Characteristics and Application Range of Die Casting Parts

  Die-casting is a kind of pressure-casting parts. It is a pressure-casting mechanical die-casting machine equipped with a casting mold. The metal such as copper, zinc, aluminum or aluminum alloy heated...