Permeability and mechanical resistance of shells ceramics used in the process of precision investment casting

Abstract

The process of smelting to the lost wax provides great amount of pieces to the industry, with an excellent superficial completion, reduce dimensional tolerances and quite complex forms. One of the most important stages of the process is the construction of the shells or ceramic molds, since when these do not fulfill the necessary requirements they reveal relatively high indices of failure, that influence directly in the quality of the pieces, thus providing, a great number of products not conform. The present study shows the characterization of the ceramics molds silica-based agglomerates with ethyl silicate, starting off of a experimental design of 22, where is evaluates the permeability and mechanical resistance of the shell (Resistance to flexion MOR), varying the thickness and the drying time. Next identifies the microstructure of green mold, calcined and sintered, using the technique of scanning electron microscopy and finally relates the microstructure obtained with the two properties mentioned.