The antenna splitters of the Xiaomi Mi4 smartphone placed multiple demands on material selection and DSM Engineering Plastics said Xiaomi selected its Stanyl ForTii polyamide to meet its needs. Key factors highlighted by DSM are Stanyl ForTii’s mechanical performance, high flowability, colour stability and chemical resistance.

The ends of the phone’s exterior metal frame need to be electrically disconnected, and a plastic frame splitter is used to mechanically connect them, with the splitter needing to perform well in strength terms. The splitter and metal frame are attached to each other using an insert moulding process, so an extremely high flowability is required for the material.

As the frame splitter is an exterior part, there is a very high demand on its aesthetics, such as colour. The final part has to undergo 80???-100??? high-temperature procedures and cleaning processes in strong alkaline solution, therefore demanding high requirements on colour consistency and retention of mech-anical performance. After processing, the part needs to be precision machined and the material needs to be immersed in cutting fluids, so it must be corrosion resistant.