Metal frames of smartphones present special challenge… for plastics

1214
  • Insulating antenna splitters made from polyamide
  • Processing: good flow and color stability under high-temperature required
  • Polyamide has to meet highest performance requirements

Metal frame design is currently a popular feature for trendy high-end smartphones. However, the technique to achieve reliable transmission and receipt of antenna signals with such design is a challenge. Insulating antenna splitters turn out to be an effective solution. The Chinese smartphone producer Xiaomi Technology Co., Ltd. uses Stanyl ForTii XS85 polyamide of DSM to produce this frame splitter.

antenna splitters of Xiaomi Mi4 

Xiaomi selects DSM Stanyl ForTii – for antenna splitters of Xiaomi Mi4 (source: DSM Engineering Plastics: DSMPR456)

Processing: good flow and color stability under high-temperature required

The polyamide has to meet the mechanical requirements of the mobile structure. In addition, it has to provide good flow and color stability under high-temperature and chemical processing. The polyamide grade Stanyl ForTii is being used in the frame splitters of Xiaomi Mi4. The material also provides very good dimensional stability, high stiffness and mechanical strength at high temperatures.

Polyamide has to meet highest performance requirements

Coming with a metal frame, the applications and procedures for making a frame splitter of Xiaomi Mi4 have to meet the following requirements:

  • As both metallic ends of the frame need to be electrically disconnected, a plastic frame splitter is used to mechanically connect them. The strength and tenacity of the plastic itself are very demanding, therefore it is required to be resistant to constant pulling and falling.
  • The frame splitter and metal frame are attached to each other. To perform the insert molding process, an extremely high flowability is required for the material.
  • As the frame splitter is an exterior part, there is a very high demand on esthetics such as color.
  • The final part has to undergo 80?-100? high-temperature procedures and cleaning processes in strong alkaline solution, therefore demanding high requirements on color consistency and retention of mechanics.
  • After processing, the part needs to be precision machined and the material needs to be immersed in cutting fluids. It must be corrosion resistant.


Related Articles & Comments

Comments are closed.