ABSTRACT
This chapter discusses how to measure the mechanical properties of a powder bed and how to describe the mechanical strength or flow ability of a powder bed based on the powder mechanics. The mechanical properties of powder such as adhesion, cohesion, and flow ability have an effect on powder handling and operation. A cylindrical specimen is placed into the space surrounded by two pistons and a rubber side membrane, to which vertical and lateral pressures are applied independently. The tester imposes known uniform principal stresses on a precisely compacted cubical sample powder and measures the resulting strains in a simple and immediate manner. A direct shear tester has a simple structure and the testing procedure is simple. On the Jenike’s shear tester, Haaker investigated the effect of the ratio of externally applied load during consolidation and preshearing. Hiestand and Wilcox and Budny devised a parallel-plate tester, and Hirota et al.
