Case Study: Transmission Laser Welding of a Filter

The Transmission laser welding is a relatively new method of joining thermoplastic materials. A laser beam in the near infrared region of the spectrum will pass through thermoplastics yet will be absorbed into additives in the material such as pigments, bulk fillers and strengthening media. This case study has used a relatively new type of laser, a high power direct diode laser array to weld two halves of a filter for the automotive sector. The welding methodology used for the filter is discussed; results showed no failures in the welded joint with typical burst pressures of ∼400-psi being recorded against a safe operating pressure requirement of 175-psi. The process is being implemented for production of the filter in the coming year.