Binder removal is a crucial step to obtain high quality compacts in powder injection molding process. In this study, a two-dimensional wick-debinding model was developed on the basis of Darcy's law and numerically solved by the body-fitted finite element method. A statistical model relates debinding time to designed effective factors, such as compact thickness, powder diameter, and fractional packing density, and it is also built by response surface methodology. Results show that the most significant factor on debinding time is the compact thickness, followed by compact powder diameter, compact packing density, and wick powder diameter. However, the effect of wick packing density on debinding time is not significant. Meanwhile, the total percentage of the predicted values is within 1% tolerance corresponding to the experimental values. This indicates that the proposed model looks reasonably accurate. Based on the desirability function approach, the minimum debinding time is about 68 seconds, corresponding to the optimal combinations of compact thickness, compact powder diameter, wick powder diameter, compact packing density, and wick packing density, 1.9 mm, 11.3μm, 0.68 μm, 0.50 and 0.32, respectively. Through the confirmation experiments, the difference of optimal debinding time between the predicted value and the experimental data is about 1.5%.
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