Influence of vacuum on adjusting parameters of high pressure die casting parts from alloy AlSi9Cu3(Fe)

In paper authors present the influence of adjusting key parameter, which is changeover point between first and second phase, on quality of casting from AlSi9Cu3(Fe) alloy. Technological tests were carried out in industrial conditions on a machine with a clamping force of 1200 Mg with variable parameters of the piston operation. Production practice has shown that with inappropriate selection of parameters, on the final products significant casting defects appear in the form of: drags, delaminations, sticking of castings on the mould and discoloration associated with uneven filling of the mould cavity. Based on the temperature distribution of the mould, the spray head was checked for correct operation and its impact on defects was eliminated. The filling of the mould was checked at the time of switching the second phase with the vacuum turned on and off in the mould cavity. It was shown that the key parameter is the appropriate selection of the changeover point of the second phase which is influenced by the vacuum in the cavity of closed mould.