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Porous Metal Design Guidebook
Introduction and Definitions
This article provides general information about porous sintered metals made from metal powders, describes methods of manufacture and includes information concerning design data and applications. Porous metal materials have engineered, inter-connected porosity that are fabricated from metal powder particles using powder metallurgy (PM) techniques. The following terms are helpful for understanding industry definitions and related standards: Pores- The open volume within the metal matrix or network. Interconnected Porosity- Pores that are connected together and to the surfaces of the component to allow fluid flow from one side to the other. By contrast, isolated pores do not have connectivity to both surfaces to allow fluid flow. Percent Porosity- a rough measure of the open volume equal to 100% minus the part density. The total open volumes of interconnected and isolated porosity are normally included in this value. Pore Shape, Pore Size and Pore Size Distribution are critical factors when describing the open volume available. Particle Retention Rating- indication of the size of the particles removed from a fluid during filtration. The test method and filtration efficiency must be specified to compare particle retention ratings of filters.