Ni-based composite microstructures fabricated by femtosecond laser reductive sintering of NiO/Cr mixed nanoparticles

Abstract

Ni-based composite micropatterns were fabricated by the femtosecond laser reductive sintering of NiO/Cr mixed nanoparticles. A NiO/Cr mixed nanoparticle solution including ethylene glycol and polyvinylpyrrolidone was irradiated with focused femtosecond laser pulses. The X-ray diffraction spectra of the fabricated micropatterns indicated that NiO nanoparticles were well reduced under atmospheric conditions in the laser scanning speed range of 5–15 mm/s. In contrast, micropatterns including NiO were formed at a laser scanning speed of 1 mm/s, indicating that the reduced Ni was reoxidized by overheating. These results were supported by those of energy-dispersive X-ray spectrometry analysis and the electrical resistivity of the micropatterns. The compositions such as Ni, NiO, Cr2O3, and Ni–Cr in the fabricated micropatterns depended on laser scanning speed. The selective fabrication of a ferromagnetic free microgear from the substrate and an axis fixed on the substrate was demonstrated by controlling the laser scanning speed. The fabrication process for Ni-based composite microstructures is useful for the fabrication of ferromagnetic microdevices.

Effect of Heat Accumulation on Femtosecond Laser Reductive Sintering of Mixed CuO/NiO Nanoparticles

“…We have also developed a process for femtosecond laser reductive sintering of metal oxide NPs [ 12 , 13 , 14 ]. Femtosecond laser pulses are effective for controlling the reduction and reoxidization of the micropatterns.…”

“…We have used this process to fabricate Cu/Cu 2 O composite micro-thermistors. Furthermore, NP solutions with the mixtures of NiO/Cr and CuO/NiO have enabled us to form Cu-Ni alloys and Ni/Cr-O composite micropatterns, respectively [ 13 , 14 ]. Ni/Cr-O microgears were successfully fabricated, and they could be moved by controlling an external magnetic field.…”

Laser digital patterning of conductive electrodes using metal oxide nanomaterials

“…The LDP process of NiO NPs has also been employed to produce Ni-based composite microstructures. Mizoshiri et al used a high-repetition rate femtosecond laser (λ = 780 nm, pulse width = 120 fs, repetition rate = 80 MHz) to fabricate Ni-Cu/NiO-Cu 2 O micropatterns using a mixture of NiO and CuO NPs [82,83] and fabricate Ni-Cr composites using NiO/Cr mixed NPs [110]. In these studies, the authors manipulated the laser scanning speed to control the chemical compositions of the composites.…”

Copper and Nickel Microsensors Produced by Selective Laser Reductive Sintering for Non-Enzymatic Glucose Detection

“…In recent, 3D printing technologies have become a popular tool for solving a number of scientific problems [ 24 ]. Selective laser sintering (SLS) and selective laser manufacturing (SLM) for 3D microstructures are very promising representatives of such modern techniques [ 25 ]. In general, SLS is an additive manufacturing method that can be implemented for formation of 3D structures of a given size and shape by heating powders of various materials (plastic, glass, ceramics, metals) with the focused laser beam up to temperature, at which the powder-like particles fuse together providing the porosity control regime.…”

“…SLM is already actively applied in production of the electrochemical sensors based on metals and their alloys suitable for detection of phenols [ 26 ] or explosives and nerve agents [ 27 ]. Other noticeable techniques that can be utilized for the aforementioned purposes are: roll-to-roll printing (R2R) [ 28 ], inkjet printing [ 29 ], screen printing [ 30 ], chemical vapor deposition (CVD) [ 31 ], laser-induced metal deposition (LCLD) [ 32 ], femtosecond laser reductive sintering of metal oxide nanoparticles [ 25 , 33 , 34 , 35 ], etc. At some level all these methods demonstrate different drawbacks mostly related to cost, maintenance, complexity, efficiency and others.…”