«The booming international smartphone market offers huge potential for powder injection moulding», says Hartmut Walcher, PIM expert at Arburg. «Because this process enables the use of materials such as stainless steel, titanium and zirconium oxide, requires much lower material volumes and is significantly more cost-effective than machining».
Innovative smartphone application
In a joint project with BASF, Arburg injection moulded exemplarily thin-walled, stress and segregation-free smartphone backs made from metal powder for the first time worldwide at the leading industry trade fair, World PM2016. The associated changeable mould is designed so that it can alternatively be used to produce frames for smartphone housings as well as backs. Trade visitors to the Technology Days 2017 also have the opportunity to view this sophisticated application and see at first hand how the biggest challenges in the injection moulding of thin-walled metal components were solved: complete mould filling and minimising distortion during the subsequent sintering process.
Constant green compact density
The exhibit uses a hydraulic Allrounder Golden 470 C Edition with a clamping force of 1,500 kN and PIM equipment. The injection moulding machine processes the flow-optimised Catamold 17-4 PH Plus feedstock from BASF to produce a green compact for a smartphone back in Arburg design, with a thickness of around only 1 millimetre and a length of 136 millimetres. The cycle time is around 55 seconds. In order to maintain consistent green density over the entire component, the mould is dynamically temperature controlled with a hot runner with liquid temperature control. This produces very good surface finishes, which can subsequently be polished to a high gloss. A linear Multilift Select robotic system gently removes the moulded green compacts and sets them down on a slide rail.
Over 50 years of PIM experience
Injection moulding machine manufacturer Arburg has more than 50 years of experience in powder injection moulding and has produced far in excess of 1,000 PIM machines for a broad range of applications and industries, including the automotive, jewellery and watch industries, as well as the IT and dental sectors. The company’s expertise ranges from feedstock preparation and the complex manufacturing of micro-PIM parts through to cost-effective component assembly integration and the design and implementation of complete turnkey systems. Furthermore, in addition to injection moulding, all upstream and downstream production steps such as material preparation, debinding, sintering and part analyses can also be tested under practical conditions at its in-house PIM laboratory.