"Why would you use vacuum in HPDC?" Julien Bobst, Area Sales Manager at Fondarex SA, recently posed this question to the LinkedIn community. The non-representative survey drew 34 participants, 47 % of whom chose the answer option "Improve parts quality." Other options included "Resolve cavity filling issues" (32 %), "For structural & safety parts" (12 %) and "Surfaces aspects & treatment" (9 %).
But how can vacuum in HPDC fulfill these aspects? We asked Julien Bobst in more detail:
In general the best way to increase the quality of the parts is to remove the gas porosity. In this case the results are coming out much better! The reject rate is reducing on the HPDCM and generates more good parts.
Cavity filling issues are resolved by removing the air entrapped inside a complex geometry of the mold. The filling during the injection with the vacuum will be more easy and you can decrease the specific pressure of the HPDCM to fill the cavity. The life time of the mold will also be increased due to this modification of the process.
The production of structural parts is impossible without the vacuum technology. The technical aspect must be reached. The complexity of the design (geometry), the thickness requirements, the mechanical characteristic to reach are very high. It is also mandatory to have the high quality standards for safety parts.
How structural components for automotive applications are actually defined and how their physical properties can be achieved is explained by Robert Knorre, Managing Director, DruckGussBeratung.
The parts for surface quality or surface treatment will be better with the vacuum technology. By reducing the gas porosity on the surface, the parts are more resistant for any further treatment and the appearance is ameliorated.
