Development of Thermal Spraying and Coating Techniques by Using Thixotropic Slurries Including Metals and Ceramics Particles

Abstract

Abstract. Thermal nanoparticles coating and microlines patterning were newly developed as novel technologies to fabricate fine ceramics layers and geometrical intermetallics patterns for mechanical properties modulations of practical alloys substrates. Nanometer sized alumina particles were dispersed into acrylic liquid resins, and the obtained slurries were sputtered by using compressed air jet. The slurry mists could blow into the arc plasma with argon gas spraying. On stainless steels substrates, the fine surface layers with high wear resistance were formed. In cross sectional microstructures of the coated layers, micromater sized cracks or pores were not observed. Subsequently, pure aluminum particles were dispersed into photo solidified acrylic resins, and the slurry was spread on the stainless steel substrates by using a mechanical knife blade. On the substrates, microline patterns with self similar fractal structures were drawn and fixed by using scanning of an ultra violet laser beam. The patterned pure metal particles were heated by the argon arc plasma spray assisting, and the intermetallics or alloys phases with high hardness were created through reaction diffusions. Microstructures in the coated layers and the patterned lines were observed by using a scanning electron microscopy. IntroductionThermal nanoparticles spraying had newly developed as a novel coating technique to create fine ceramic layers without structural defects on practical alloys substrates [1,2]. The nanometer sized alumina ceramic particles were dispersed into liquid resins. Fluid viscosity of the mixt pastes were measured and optimized to realize homogenized particles dispersions and smooth slurry flows. The obtained thixotropic slurry of rheological flow was sputtered by using compressed air jet, and the slurry mist blew into the arc plasma with an argon gas spraying. On a stainless steel substrate, the ceramic layers were formed. The formation of micro cracks and pores in the coated layers will be discussed by scanning electron microscope observations. Subsequently, thermal microline patterning to realize metal phases drawing on the alloys substrates had been developed [3,4]. Micrometer sized pure aluminum particles were dispersed into the photo solidified liquid resins. The slurry pastes were spread on the stainless steel substrate, and micro patterns were drawn and fixed by using an ultra violet laser scanning. The patterned pure metal particles were heated by the argon arc plasma spraying, and the intermetallics and alloys phases with high hardness were created through reaction diffusions. Microstructures and composite distributions in the vicinity of formed alloy and metal interfaces were observed and analyzed by using an electron microscope. Load dispersion abilities of the network were evaluated by using conventional mechanical tests and compared with simulated and visualized profiles by using a numerical analysis simulation. The modulation effects of stress distributions on the material surfaces by design and fabrication o...

Stereolithographic additive manufacturing of acoustic devices with spatially modulated cavities

“…Multidimensional periodic, graded, fluctuated, and self‐similar structures could be successfully elaborated. Distribution profiles of energy propagations and material flows are spatially modulated for environmental compatibilities 9–14 …”

“…Distribution profiles of energy propagations and material flows are spatially modulated for environmental compatibilities. [9][10][11][12][13][14] Acoustic modules can theoretically harmonize resonates with comparable sound waves. Ceramic components with high rigidities were systematically fabricated for the profile modulations of the resonation spectra.…”