Permeability

1) Magnetic permeability, a measure of a material’s ability to alter the magnetic field around it, defined as the ratio of the magnetic induction to the intensity of the magnetizing field. 2) The ability of a porous material to permit pressurized gas or liquid passing through it, e.g., in a mold, the porosity of foundry sands and the ability of trapped gases to escape through the sand. 3) A parameter for ranking ease of liquid or gas to flow through a barrier.