Selection of Laser Plastic Welding Materials

The welding object of plastic laser welding is thermoplastic plastic materials. Thermoplastic plastic materials are mainly divided into two categories, one is amorphous plastics, and when no color masterbatch is added, they are transparent materials, such as PC, PMMA and other materials; The other type is semi-crystalline plastic, which is milky white or milky yellow without adding color masterbatch, such as PA, PBT, etc.

For the upper layer of laser-penetrating plastic, all natural plastics without color masterbatch are transparent to 800-1000nm laser. If an amorphous material is used, there is no specific requirement for its thickness. If a semi-crystalline material is used as the laser penetration layer, generally speaking, the design thickness of the penetration layer plastic in the welding area should not exceed 2mm. The addition of glass fiber has a certain influence on the laser penetration. The more glass fiber is added, the smaller the plastic design thickness of the laser penetration layer should be.

For the lower layer of light-absorbing plastic, ordinary black plastic can be used.

        Many customers inquire about welding between colored plastic combinations. Generally speaking, the welding difficulty and cost follow the table below:

The simplest is to use the natural color light-transmitting plastic to weld on the black light-absorbing plastic. The laser plastic welding process is the simplest and the lowest cost. The most common combination used in automotive parts welding applications is black laser penetrating plastic laser welding on black light absorbing plastic. The difficulty is to use black laser penetrating plastic. When selecting materials, laser penetrating parts must be Use a laser with acceptable transmittance to penetrate plastic.

The most difficult is the laser welding between colored plastics, the welding between transparent plastics and transparent plastics, and the most difficult is the welding between white and white plastics. Huazhuo Technology has realized the welding between transparent plastics and transparent plastics as early as 2017, and has also realized the welding between some white plastics and white plastics in 2020. I believe that in the near future, Huazhuo can overcome this difficulty.