Papers by Author: Zi Yu Zhao

Abstract: Thermally enhanced machining is an effective way of processing hard and brittle materials. The Wear performance of diamond saw blade cutting granite plate by Plasma-assisted heating is studied by a homemade experimental device. Investigation of the blade wear in different suspension and heating scan rate shows that by plasma arc heating, the tool wear rate has a significant reduction. A technology for the efficient stone machining and further industrial applications is provided in this paper.

Abstract: Experimental system of CCD real-time acquisition is developed according to high temperature property of plasma jet. Mathematical model of gray image and jet temperature distribution is established and basic principles of the CCD collection is analyzed. It realizes acquisition by a common image acquisition card in LabVIEW environment and real-time display of jet. Jet is collected on the computer image processing by using IMAQ Vision, and it intuitive analyzes the shape and temperature distribution according to pseudo-color image processing results of the jet temperature field. Experimental results deepen understanding of the complex nature of plasma jet, which have a guiding significance on the plasma technology in materials processing application.

Abstract: Based on the gas tungsten arc welding process this paper investigated the welding temperature field measurement and simulation of 945 steel plate and AZ31B magnesium alloy, using a non-contact and fast response measured temperature method-Infrared Radiation (IR)-which utilized the baffle to remove the arc and hot tungsten electrode interference, the top-face temperature of AZ31B magnesium alloy plate and 945 steel plate. The results indicated that the lengthwise isothermal map of 945 steel plate is much longer than that of AZ31B magnesium alloy plate, which leads to the most temperature field information loss, this is because the thermal conductivity of steel is small and decreases with temperature increase, the thermal conductivity of AZ31B magnesium alloy is much bigger that that of the 945 steel, about 1.5 times of 945 steel, and increased with temperature increase. The results also showed using IR to measure the welding temperature of magnesium alloy is more difficult than 945 steel. Keywords: magnesium alloy, high strength steel, welding temperature field, IR

Abstract: This paper studies the thermal interaction of Ni particle and Al particle setting in the carbon steel surface using ANSYS software by finite element numerical simulation. It highlights the temperature-time change of feature points that are at different locations of flattened particles and substrate, and micro-contact heat transfer of particle and substrate surface is also analyzed. The results help to study residual stress distribution of a splat particle in the plasma spray forming, which further provide an important basis for improving the quality of the coating.

Abstract: Splat deposition is an important part influencing coating quality in plasma spray forming. Flatten behavior of a single Ni droplet falling on a smooth substrate is evaluated by numerical simulation of ANSYS software, this paper meanwhile researches a single Ni particle deposition in the surface of flattened Al₂O₃ sheet and thin Al particles, the impact factors of particles flattening and the mechanism of the interaction between particles are also studied. The results have benefit to improving the coating porosity and bond strength between particles.

Abstract: In this paper the influence of gypsum-water ratio, filler types and calcination temperature on gypsum bending strength were analyzed by the means of experiments. Spiral-shaped gypsum mold was made by gypsum molding material and mobility experiment was conducted on Pb-Sn alloys. Compared with pure gypsum, gypsum mixture had better mechanical properties. The fluidity of the alloy in the gypsum mold was prone to casting pressure, pouring temperature and alloy ratio. The research results have benefit to the development of gypsum casting technology.