RSP Production Method: meltspinning process
During the meltspinning process, liquid (molten) aluminum (800˚C) is poured onto a fast-rotating copper wheel. Almost instantaneously an unbroken metal ribbon is formed at 20˚C (room temperature), in fact, the material "freezes" (solidifies) in the same shape as it was in its liquid state. In this way the homogeneous crystalline structure of the aluminium alloy is stored in the material. The term 'Rapid Solidification' originates from the sudden drop in temperature of about 1.000.000 ˚C per second (converted) as the aluminium comes in contact with the wheel. The ribbon is cut into small pieces and via a few production steps transformed into a machinable product. Depending on the type of alloy required, a special heat treatment may be applied.
RSP Microstructure
Aluminum as strong as titanium. Owing to the superfast solidification in the melt-spinning process, the crystalline structure within the material is very small (± 2 micron). The various intermetallic compounds as well as the components with a low solubility are distributed finely and homogeneously over the metal matrix, thereby forming a very homogeneous microstructure. To a great extent, these factors contribute to the higher strength of RSP alloys.
The two pictures below show the difference in microstructure between an RSP alloy and a conventionally cast aluminum alloy, although they are identical in chemical composition.
