Sand Molds: The characteristic of the molding material which permits gases to pass through it.
(2) Powder Metallurgy: The property which indicates the rate at which a liquid or gas will pass through a sintered powdered metal compact.
(3) Magnetism: a term used to express the relationship between magnetic induction and magnetizing force. Stated another way, it is the affinity of a substance to conduct or carry magnetic lines of force.
