TY - JOUR N2 - The presented work is aimed to deal with the influence of changes in the value of negative (relative) pressure maintained in the die cavity of pressure die casting machine on the surface quality of pressure castings. The examinations were held by means of the modified Vertacast pressure die casting machine equipped with a vacuum system. Castings were produced for the parameters selected on the basis of previous experiments, i.e. for the plunger velocity in the second stage of injection at the level of 4 m/s, the pouring temperature of the alloy equal to 640°C, and the die temperature of 150°C. The examinations were carried on for three selected values of negative gauge pressure: - 0.03, - 0.05, and - 0.07 MPa. The quality of casting was evaluated by comparing the results of the surface roughness measurements performed for randomly selected castings. The surface roughness was measured by means of Hommel Tester T1000. After a series of measurements it was found that the smoothest surface is exhibited by castings produced at negative gauge pressure value of - 0.07 MPa. L1 - http://journals.pan.pl/Content/87946/PDF/05_paper.pdf L2 - http://journals.pan.pl/Content/87946 PY - 2014 IS - No 2 DO - 10.2478/afe-2014-0030 KW - Innovative foundry technologies KW - aluminium alloys KW - Vacuum assisted high pressure die casting KW - surface roughness KW - Defectsin pressure die castings A1 - Konopka, Z. A1 - Łągiewka, M. A1 - Zyska, A. A1 - Nadolski, M. PB - The Katowice Branch of the Polish Academy of Sciences DA - 2014 T1 - The Effect of Vacuum Assistance on the Quality of Castings Produced by High Pressure Die Casting Method UR - http://journals.pan.pl/dlibra/publication/edition/87946 T2 - Archives of Foundry Engineering ER -