Abstract
The effects of the dimension of a movable plate, the twist condition and the roughness of the surfaces of the movable plate and fixed plate in contact with the powder on the powder yield locus (P. Y. L.) measured by a direct shear tester with parallel plates are examined.
From the results, the proper experimental conditions are as follows:
1) The dimension of the movable plate have an effect on P. Y. L., and so the suitable dimension for measurement are determined.
2) A normal stress of about 0.28kPa is suitable for the twist.
3) The surfaces of the movable plate and fixed plate have an irregular roughness like sand paper which is better than a surface which has a regular roughness, such as notching.
Furthermore, as a result of measuring several powders at the above proper conditions, . it is recognized that fc/γg is more suitable to evaluate the flowability of powders than σp/fc.
