Generation of radial striations on particulate coated magnetic disks

The expression derived by R. Hansen and D.L. Hunston (1974) defines the parameters responsible for the spokes or radial waves formed during the high-rpm spin-coating of magnetic particles on 35.6-cm-diameter aluminum substrates; namely, velocity, fluid density, and shear modulus. Experimental work was carried out to determine if this expression could approximately describe the spoking phenomenon observed during the coating application process for particulate rigid disks.<>