The Situation
Semi‑solid forming of aluminium has proven to be an effective solution for the production of high integrity parts.
The Problem
Semi‑solid forming processes based upon billet reheating (thixocasting) incur a significant cost penalty resulting from electrical energy consumption, raw materials premiums and the inability of the user to recycle process scrap internally.
The Solution
In order to overcome this problem, a liquid‑based method (rheocasting) of producing feedstock for semi‑solid casting has been developed.
The SEED technology has been demonstrated on a wide variety of aluminium alloys including foundry alloys (2xx, 3xx, 7xx) and wrought compositions (6xxx). Shot weights and dimensions can be readily adjusted and the process can be retrofitted to both horizontal and vertical die/squeeze casting machines. A fully automatic industrial version of the SEED technology is now available, with three units already in operation throughout the world.
The Advantages
1. SIMPLICITY
· The technology is liquid‑based (rheocasting), and returns can be fully reused.
· Very consistent slurry: the very simple approach gives excellent slurry behaviour.
· No need for close temperature control: minimum control is required while offering a large operating window.
2. ADDRESSING USERS REQUIREMENTS
· Footprint / Cycle time
· Flexibility / Robustness
· Repeatability / Retrofittability
· Wide alloy range