COMPRESSION DEFORMATION OF CLAY GREEN BODY FOR TRADITIONAL CERAMICS

A uniaxial compression test was carried out to investigate deformation behavior of clay green body for wet-pressing. Green bodies containing 25-35 mass% water were prepared from Hara gairome clay and distilled water. The samples were formed into column having various dimensions ( 20 mm phi x 30 mmh, 20 mm phi x 15 mmh, 20 mm phi x 10 mmh, 33 mm phi x 10 mmh) and were largely deformed by compression under a compression rate of 1.0 mm . s(-1). When the stress-strain curves were converted to the stress-diameter/height curves according to the plastic deformat ion theory, the yield points and the linear relationships between stre ss and diameter/height were observed, which were well represented by a plastic deformation equation of uniaxial compression under full-surfa ce-sticking, since the ratio of the slope of the line over the yield p oint were close to 0.19. The yield points increased with decreasing wa ter content. The sticking was due to the adhesion between the steel di e and the samples. In conclusion, it is found that the compression def ormation of clay green body can be well characterized by using a uniax ial compression test.