Vacuum and foaming moulds, thermoforming tools
Vacuum forming and thermoforming are processes for forming thermoplastics.
In these processes, special aluminum molds with vacuum holes or steam nozzles are often used. Porous metals are being increasingly used for these purposes.
Porous aluminum is excellently suited for the production of foaming and thermoforming moulds:
– completely permeable, eliminates the need to drill vacuum holes or steam nozzles
– Aluminum is a very good heat-conducting metal and thus ensures the rapid cooling of the mould
– High strength thanks to cast structure, thus long life time of the porous aluminum molds
Compared to conventional forms of solid aluminum
1) complex shapes without vacuum holes or steam nozzles
In the production of molds made of solid aluminum quite complex shapes are often not implementable. The reason for this is the inability to create channels for vacuum or steam in such difficult forms. It can also be very difficult to bring vacuum or steam to such channels.
Thanks to the uniform distribution of pores in porous aluminum and its permeability in all directions, it is possible to produce the most complex shapes without restrictions.
2) even distribution of vacuum or steam
The surface of the porous aluminum consists to 55-65% of pores. This ensures an absolutely even supply of vacuum or steam at each point.
Thus the homogeneity of the properties of the plastic product becomes very high compared to the use of relatively infrequently arranged channels for vacuum and steam.
3) half of the weight (density 1,2-1,0 g/cm3)
The low weight of porous aluminum allows the production of lightweight molds for foaming and thermoforming tools, fiber molds. The entire construction is greatly simplified and the weight is reduced also because there are no tubes/pipes for the supply of vacuum or steam necessary.
4) half of the heat capacity
5) rapid prototype production from prefabricated blocks
You can process porous aluminum under special machining conditions on lathe machines, milling benches and also with the help of other mechanical equipment. This allows you to quickly create complex molds for the production of prototypes or series production.
6) Working temperature up to 250…550 °C
Porous aluminum is a cast material, it contains no bonding agents such as glue or resin and can also be used at high temperatures.
Porous aluminum has a unique combination of material properties:
– all products are complete permeable
– can be made to large formats and in any shape
– high strength thanks to cast structure
– different and controllable pore sizes
– homogeneous distribution of the pores over the entire volume