Design & Engineering
The design and engineering process for an aluminum forging is a complex, multi-stage process that ensures the final product meets specific performance and quality requirements. It starts with a customer’s request and ends with a finished, high-performance part.
Design Phase
The process begins with the customer’s design, which includes the part’s geometry, dimensions, material specifications, and required mechanical properties. Engineers review this design to ensure it is suitable for the forging process. They consider factors like draft angles, fillet radii, and parting lines. A forging feasibility study is conducted to determine if the part can be forged efficiently and cost-effectively.
Next, a forging simulation is performed using specialized software like Transvalor. This software simulates the metal flow, stress, strain, and temperature changes during the forging process. This allows engineers to identify potential laps, folds, or incomplete fills and optimize the die design. The simulation also predicts grain flow, which is critical for the final part’s strength.
Tooling Engineering
After the design is finalized, the tooling (dies) is engineered. This is a critical step because the die design directly impacts the quality and cost of the forged part. The tooling is designed to create a “near-net shape” part, minimizing the need for subsequent machining.
The tooling design process involves several steps:
- Die Block Selection: Choosing the correct steel alloy for the die block, which must withstand high temperatures and pressures.
- Die Cavity Design: Creating the impression of the part’s shape in the die block.
- Flash Gutter Design: A gutter is designed around the die cavity to allow excess material (flash) to flow out, ensuring the die cavities are completely filled.
- Die Machining: The impression is machined into the die block using CNC (Computer Numerical Control) machines.
Forging Process Engineering
The final stage is the process engineering of the forging itself. This involves determining the optimal sequence of steps to transform a raw aluminum billet into the finished forged part.
- Material Selection: The specific aluminum alloy is chosen based on the required mechanical properties, such as strength, toughness, and corrosion resistance. Common alloys for forging include 6061 and 7075. Aluminum material can be either extruded or cast rod. The customer decides on what material is to be used.
- Billet Preparation: The aluminum billet is cut to the precise size and weight needed for the part.
- Heating: The billet is heated to the specific forging temperature, which for aluminum is typically between 750°F and 850°F (400°C to 455°C).
- Forging Sequence: The billet is placed in the forging press and shaped in one or more stages (e.g., pre-form, finish forging). This process aligns the grain structure of the aluminum, which significantly enhances the part’s strength.
- Trimming: The excess flash is trimmed from the forged part.
- Heat Treatment: The forged part undergoes a final heat treatment, often involving solution heat treatment and artificial aging, to achieve its final mechanical properties.
- Finishing: Shot blasting, vibratory cleaning, and polishing creates the perfect visual finish.
- Quality Control: The final part is inspected for dimensional accuracy, surface finish, and defects using methods like CMM (Coordinate Measuring Machine) and non-destructive testing (NDT).