For welding of plastics the material has to be molten at the interface. During welding the temperature of the melt must not exceed the disintegration temperature of the material. For cutting of plastics the material in general is sublimated by the laser radiation. In the following, some aspects of the processing of plastics by laser radiation in comparison with the processing of metals by laser radiation will be discussed. An quantitative estimation for process of welding of plastics will be given. The theoretical values are compared with experimental results. The influence of wavelength of the laser radiation at the penetration depth are discussed. Some examples for cutting of composite plastics are given. (ILT)
