Laser ablation of quasicrystalline materials is a promising method for creating micro- and nanostructures with unique physical and chemical properties. In this paper, the effect of solvent and power on the ablation of quasicrystalline Al–Cu–Fe alloy using a nanosecond pulsed laser was investigated.
The experiments were conducted in two different environments: air and immersion of the sample in deionized water. It was found that the nature of the ablation significantly depends on the environment. In air, craters with clearly defined melted edges are formed, while in water, ablation occurs more gently, with less thermal impact on the surrounding material.
Nanosecond laser pulses were used to fabricate Cu/CuO/FeO4 and Al2O3 nanocomposite materials by ablation of quasicrystalline Al–Cu–Fe (QC) alloy in two different liquid media: ethanol and deionized water. The ablation process lasted 15 min at two laser power levels, 40 J/cm2 and 80 J/cm2, in each medium. Microscopic and spectroscopic methods were used to analyze the effect of solvents to understand the structural and morphological changes of the nanoparticles.
Analysis using X-ray diffraction (XRD), selected area electron diffraction (SAED) and Raman spectroscopy showed the formation of Cu/CuO/Fe3O4 and Al2O3 nanocomposites in both environments. In addition, the formation of core-shell nanoparticles was detected by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM).
However, in the case of using deionized water, hollow nanoparticles consisting of copper, iron and aluminum oxides were obtained. The formation of these two structures in different environments is due to the Kirkendall diffusion process, which probably depends on the physical characteristics of the solvent, including thermal conductivity, viscosity and polarity. Based on the experimental data obtained, a probable mechanism for the formation of the observed morphology is discussed.
A study of the effect of laser radiation power showed that increasing the power leads to an increase in the depth and diameter of the ablation crater. At low powers, material evaporation predominates, while at high powers, the mechanism of melting and melt ejection dominates. Analysis of the elemental composition of the ablation torch by optical emission spectroscopy showed the presence of Al, Cu and Fe atoms, which indicates the congruent nature of ablation.
The obtained results demonstrate the possibility of controlled laser ablation of quasi-crystalline materials by selecting the optimal parameters of laser radiation and the environment. This opens up prospects for the creation of new functional materials and devices based on quasi-crystals.
Author: R.Rawata, A. Tiwari, N. Arun, SVS Nageswara Rao, A.P. Pathak, Yagnesh Shadangi, N.K. Mukhopadhyay, S. Venugopal Rao, A. Tripathi
Institute: Department of Physics, School of Physical Sciences, Sikkim University 6th mile Samdur, 737102, Sikkim, India, School of Physics, University of Hyderabad, Hyderabad, 500046, Telangana, India, Center for Advanced Studies in Electronics Science and Technology (CASEST), University of Hyderabad, Hyderabad, 500046, Telangana, India, Department of Metallurgical Engineering, Indian Institute of Technology (BHU), Varanasi Varanasi, 221005, Uttar Pradesh, India, Advanced Center of Research in High Energy Materials (ACRHEM), University of Hyderabad, Hyderabad, 500046, Telangana, India