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Advanced ceramic products are widely used in aerospace, automotive, electronic, laboratory equipment, and other industries. To achieve the geometric complexity and desirable properties that are difficult to obtain by conventional manufacturing methods, ceramic additive manufacturing (AM) methods have been studied intensively in recent years. However, the adaptive control with feedback is not currently implemented in any commercially available ceramic threedimensional printer. Robocasting is one of the most widely utilized constantvolumetric-flow AM processes for creating various ceramic materials at a low cost. This study employed robocasting as a model to implement an adaptive control with a feedback loop in the ceramic AM process. In this research, processing load that was proportional to the processing pressure, width of the print, and length of extrusion were selected to be representative of process signal, quality signal, and control parameter, respectively. First, a database of the load and extrusion length was established. An artificial neural network model was created using that established database. The data-driven, closed-loop control was integrated into the robocasting process. Finally, the improvement was validated by comparing the quality of the prints produced by both the closed-loop process with the adaptive control and the open-loop process without the adaptive control.

In this study, the effects of microstructure, surface roughness, and surface porosity on the corrosion behavior of direct metal laser sintered (DMLS) Ti-6Al-4V were experimentally investigated. The electrochemical measurements were conducted using a three-electrode setup setting, with the specimens in RingerÕs solution at 37°C. The acicular microstructure in the DMLS Ti-6Al-4V samples resulted in greater corrosion resistance than that of the Grade 5 alloy with an equiaxed microstructure. Electrochemical study results indicated that microstructure and surface roughness had a significant influence on the corrosion behavior of the samples. Pits and cracks were observed near the edges of the original surface pores in the as-printed samples after a 1-month immersion in simulated body fluid. The results showed that the acicular microstructure with a small number of surface pores and a smooth surface led to more desirable corrosion resistance.

This study aims to evaluate the effects of catalyst (MnO2) and coagulant (Li2CO3) on the properties of aerated concrete consist of Portland cement, aluminate cement, and grade I fly ash by the chemical foaming method. In this experimental investigation, the compressive strength and thermal conductivity of aerated concrete were tested by more than 70 aerated concrete specimens with catalyst ranging from 0 to 2.0% and coagulant ranging from 0 to 4.0%. The results indicated that catalyst had a positive effect on the foaming efficiency when the foaming agent percentage is 4%. The positive impact reaches the peak when the catalyst percentage on 0.4%. Outcomes show that the compressive strength of aerated concrete decreases slowly with the increase of coagulant content. Still, the thermal conductivity decreases significantly due to the pore size of the foam increases. The study also reveals that the coagulant effect on ordinary Portland cement concrete setting is not apparent.

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