ABSTRACTThe authors present data on their tests on the expansion coefficient of enamels to sheet steel and give results on their tests for cover enamels, upper and lower ground coats, and sheet steel. They find that the expansion coefficient, 0° to softening temperature, of the fired ground coat is only a little less in the region of the steel surface than the steel itself, and that it decreases within the ground coat toward the cover coat in order to approach the lower coefficient of the ground coat. They state that all previous measurements of the coefficients of sheet‐steel ground coats are not efficient. This study is being continu