Improving polymer surfaces using laser dispersion of ceramic micro and nanoparticles

Abstract

In this work, laser dispersion of ceramic micro and nanoparticles is applied to improve surface properties of thermoplastic polymers. Relevant surface properties are abrasion resistance, wettability or antimicrobial effects. By processing workpieces like casing slip-rings, sockets in cam control mechanisms of vehicles, and artificial knee-joints, new applications of technical polymers – as high-quality composite materials in chemical, medical and automotive technologies – should be established.The experimental investigations focus on qualifying single and two-step process alternatives, i.e. laser irradiation with simultaneous particle supply or with particle pre-deposition, and on the suitability of lasers with different wavelengths, such as solid-state and diode lasers as well as CO2 lasers. To assure manufacturing quality, a pyrometric process control is integrated. Technical polymers like PP, POM, PA 6, PC and different types of polyethylene with varying optical properties as well as ceramic particulate materials like Al2O3, ZrO2 and SiC with different particle shapes and sizes are investigated. In systematic experiments, particle insertion into the polymer surface with regard to homogeneous layer characteristics is optimised, using different laser beam shapes and powder supply parameters, modified sample surface roughness, enlarged surface temperatures, etc. The results are evaluated by determining functional and mechanical parameters as well as spatial particle distributions. The necessity of post-treatment is discussed.In this work, laser dispersion of ceramic micro and nanoparticles is applied to improve surface properties of thermoplastic polymers. Relevant surface properties are abrasion resistance, wettability or antimicrobial effects. By processing workpieces like casing slip-rings, sockets in cam control mechanisms of vehicles, and artificial knee-joints, new applications of technical polymers – as high-quality composite materials in chemical, medical and automotive technologies – should be established.The experimental investigations focus on qualifying single and two-step process alternatives, i.e. laser irradiation with simultaneous particle supply or with particle pre-deposition, and on the suitability of lasers with different wavelengths, such as solid-state and diode lasers as well as CO2 lasers. To assure manufacturing quality, a pyrometric process control is integrated. Technical polymers like PP, POM, PA 6, PC and different types of polyethylene with varying optical properties as well as ceramic particulat...