DISTORTION OF ALLOY BY SANDBLASTING

Purposes: To measure distortion of alloy plates caused by sandblasting , and to determine the influence on degree of distortion of type of al loy, plate thickness, and sandblasting conditions i.e. particle size o f alumina, air pressure, and duration of blasting period. Materials an d Methods: Plates were cast in a noble alloy and in a Co-Cr alloy. One end of the plates was fastened in a device, and the projecting 20 mm of the plates was sandblasted. Distortion was determined as the deflec tion of the plates at a distance of 20 mm from the mounting device. Re sults: The mean deflections varied between 0.37 mm and 1.72 mm. Plates of Co-Cr alloy showed less deflection than did plates of noble alloy. Deflection was increased by an increase in duration of the blasting, pressure, particle size of the alumina, and by a decrease in plate thi ckness.