Vacuum pressure casting
Vacuum die-casting is a die-casting process , in which during the inflow of the melt emerging gases of the encapsulant by a vacuum be removed. With the vacuum pressure casting variants, it is controlled either manually or electronically when exactly the melt is to be transferred into the muffle under pressure.
The person responsible can convince himself whether and when the liquid alloy is to be cast by means of the temperature display as well as visual control .
commitment
The largest areas of application for vacuum pressure casting are jewelry, model making and the dental sector. Here, vacuum pressure casting is mainly used to melt metals and alloys - such as silver , gold , platinum , palladium or bronze , brass , steel - at very high temperatures.
Construction of a vacuum die casting machine
- Housing with components: microprocessor-controlled induction generator, medium-frequency transformer, resonant circuit capacitors, swiveling housing (90 °)
- Control element for controlling the machine
- The melting unit consists of: inductor, crucible, insulation materials, cylinder adapter, temperature sensor (up to 1,600 ° C)
- The back contains: Interface for maintenance purposes (via GSM modem), connections for water, vacuum, compressed air (protective gas), electrical connection 230 V
Process of a vacuum pressure casting
The metal is first placed in the crucible . This is placed in an induction coil. Then the vacuum is switched on and generated. Melting then takes place by induction. If an electrically conductive metal is brought into the induction field (= melting material), the metal absorbs energy, i.e. H. it couples. Of course, this melting material is placed in a (non-conductive) ceramic crucible. The larger the "attack surface" of the melting material, the more energy is transferred, i. H. the faster the metal melts. After the inductive melting process, the metal can now be poured into the mold by pivoting the casting chamber. An overpressure then automatically arises, with the melt being pressed into the mold. It is also possible to purge the chamber with argon or protective gas, which promotes the flow behavior of alloys with an affinity for oxygen.
General
The vacuum die casting machines are available in different sizes and designs. The world's smallest vacuum die casting machine was developed and presented by the German manufacturer Indutherm.