SHRINK FIT BETWEEN A CERAMIC AND A METAL ELEMENT USING A HYBRID SHRINK FITTER - (MEASUREMENTS OF FITTING STRENGTHS)

A new type of shrink fitter, 'a hybrid shrink fitter', containing liquid such as a fusible alloy is proposed. The specimen materials are Al2O3 and Si3N4 for the shafts, SUS 304 for casings of the hybrid shrink fitters and SUS 403 for the metal rings. Fitting strengths were measured up to 600 degrees C. The fitting strengths decreased with temperatures up to 200 degrees C or 300 degrees C and increased at higher temperatures. It was found that the hybrid shrink fitter had a higher apparent coefficient of thermal expansion than the monolithic shrink fitter. The effect of the number of slits on the fitting strength at elevated temperatures was also studied. The slit was essential for improving the fitting strength. The number of slits did not affect the fitting strength-temperature relationship if the number was 2 or more. The longevity of the hybrid shrink fitter was less than that of the monolithic shrink fitter at elevated temperatures.