Characterization of aluminum, brass and steel nanoparticles after laser ablation

Abstract

Understanding the surface properties of materials at the atomic-scale level is of keen interest in advanced materials processing. An interdepartmental research group at Florida Institute of Technology is currently ablating samples using a state-of-the-art ultra-short pulse (USP) laser to create nanostructures. USP lasers are unique in that they can be used to modify or machine any substance in an almost athermal ablation process, independent of melt point or composition, due to the physics of non-linear optical absorption.This paper focuses on three metals: Aluminum, Brass and Steel and on analyzing the nanoparticles created on each sample. Laser parameters, e.g., pulse energy, repetition rate, and number of laser runs are varied to optimize the ablation process. Scanning Electron Microscopy and Scanning Probe Microscopy were used to create images of the samples. SPM proprietary software then was used to process the images and to analyze the surfaces to determine nanostructure size, composition and surface roughness. The original SPM images were then processed again, but this time using F.I.T.’s proprietary flattening algorithm and MATLAB filters. The two image processing techniques and statistical roughness parameters were then compared.This research will culminate in a materials library that will be accessible to researchers in the academic, military and commercial sectors.Understanding the surface properties of materials at the atomic-scale level is of keen interest in advanced materials processing. An interdepartmental research group at Florida Institute of Technology is currently ablating samples using a state-of-the-art ultra-short pulse (USP) laser to create nanostructures. USP lasers are unique in that they can be used to modify or machine any substance in an almost athermal ablation process, independent of melt point or composition, due to the physics of non-linear optical absorption.This paper focuses on three metals: Aluminum, Brass and Steel and on analyzing the nanoparticles created on each sample. Laser parameters, e.g., pulse energy, repetition rate, and number of laser runs are varied to optimize the ablation process. Scanning Electron Microscopy and Scanning Probe Microscopy were used to create images of the samples. SPM proprietary software then was used to process the images and to analyze the surfaces to determine nanostructure size, composition and surfac...