Embossing of LTCC green tapes allows the defined patterning of conductor paths and fluidic channels with excellent edge molding. However, basic process settings have not systematically been investigated up to now. We present a comprehensive overview, regarding basic process variables and new manufacturing approaches. Because the molding quality depends on the viscoelastic properties of the tape, rheological measurements were carried out. The influence of the basic process parameters, that is, temperature, pressure, time, and friction, were investigated systematically under the use of design of experiments. The influence of these parameters on the forming of micropatterns down to 10 μm was investigated, as also were the stress of the tape caused by the plastic deformation, the accuracy of edge molding, and the demolding behavior of the embossed tape. Optimum parameters were derived. From the analysis of variances it is clear that friction exerts the most important influence on the molding of fine patterns. Position tolerances of embossed patterns were determined and relaxation effects studied in order to ensure stable process conditions. It was possible to improve the leakage characteristics of valve seats by making use of embossed patterns such as smoothed metallization and a three-dimensional sealing ring. The leakage characteristic of valve seats could be improved by a factor of four.
Removal of COD & NH3 from Produced Water using Modified Horizontal Subsurface Flow Constructed Wetlands (HSCW)
