Laser-based Fragmentation of Microparticles for Nanoparticle Generation

Laser-based fragmentation of microparticles is a versatile method to generate engineered nanoparticles. The method allows a direct scaling and production of nanoparticle fractions and a continuous variation of the particle size by online control of the process and laser parameters without any chemical precursors. Especially properties like easy-to-clean and scratch-resistance surfaces, bioactivity and low-voltage electrical conductivity for microelectronics can have a potential effect on a growing existing market share of the automotive, medical engineering, electronics and optics branches. Due to the demand, ceramic (ZrO2, Al2O3) and metal (Cu, Ti) micro powders have been selected for the study. The nanoparticles are formed by laser cracking submicron particles carried in a constant gas stream using a nanosecond Nd:YAG laser(lambda = 532 nm). The influences of process parameters (pulse energy, gas type) on the particle size distribution and productivity of engineered nanoparticles will be examined. The size distribution of the engineered nanoparticles is determined by an online cascade impactor.