Metal injection molding (MIM) is a near net-shape process that offers the unique ability to manufacture porous components with homogeneous porosity, pore structure and permeability. MIM is a process that can significantly reduce production cost when large quantities of components with complex shape need to be delivered. In this study, MIM is used to produce porous 316L stainless steel structure from both water and gas atomized powders. The porous components made by MIM were characterized to evaluate their suitability for small pore structure applications. The porous structures were analyzed for porosity, pore size, permeability, and thermal conductivity as a function of powder type and processing conditions. A typical MIM powder (<20 mum) processed at 50 vol% loading in a binder system produced a uniform pore structure with a permeability of less than 1 (.) 10(-13) m 2 and a maximum pore radius of less than 5 mum. Water-atomized powder proved to be better suited for low-solids-loading metal injection molding (<50 vol% loading) since its irregular shape provided greater strength and fewer defects during the molding and debinding process steps. Measurements of thermal conductivity show that the water-atomized powder had less thermal conductivity (similar to2 W/m-K) than the gas-atomized powder (similar to3 W/m-K). This study shows that MIM is a suitable process that can be used to manufacture functional porous structures that require isotropic pore size and complex shape. (C) 2005 Springer Science + Business Media, Inc.
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机译：金属注射成型（MIM）是一种接近最终形状的工艺，具有制造具有均匀孔隙率，孔隙结构和渗透性的多孔部件的独特能力。当需要交付大量形状复杂的组件时，MIM是可以大大降低生产成本的过程。在这项研究中，MIM用于从水和气体雾化粉末生产多孔316L不锈钢结构。通过MIM制成的多孔部件经过表征，以评估其在小孔结构应用中的适用性。分析了多孔结构的孔隙率，孔径，渗透率和热导率，它们是粉末类型和加工条件的函数。在粘合剂体系中以50体积％的载量处理的典型MIM粉末（<20 mum）产生均匀的孔结构，其渗透率小于1（。）10（-13）m 2，最大孔半径小于5妈妈事实证明，水雾化粉末更适合于低固含量负载的金属注塑成型（加载量小于50 vol％），因为其不规则形状可在模塑和脱脂过程中提供更高的强度和更少的缺陷。热导率的测量表明，水雾化粉末的热导率（类似于2 W / m-K）比气雾化粉末（类似于3 W / m-K）小。这项研究表明，MIM是可用于制造需要各向同性孔径和复杂形状的功能性多孔结构的合适工艺。 （C）2005年Springer Science + Business Media，Inc.
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