摘要:
Although MIM (metal injection molding) has received widespread application, aluminum has not been widely used for MIM in the prior art because of the tough oxide layer that grows on aluminum particles, thus preventing metal—metal bonding between the particles. The present invention solves this problem by adding a small amount of material that forms a eutectic mixture with aluminum oxide, and therefore aids sintering, to reduce the oxide, thereby allowing intimate contact between aluminum surfaces. The process includes the ability to mold and then sinter the feedstock into the form of compacted items of intricate shapes, small sizes (if needed), and densities of about 95% of bulk.
摘要:
A method to form a combined enclosure and heat sink structure for a semiconductor device is achieved. A first feedstock comprising a first mixture of powdered metal materials, lubricants, and binders is prepared. A second feedstock comprising a second mixture of powdered metal materials, lubricants, and binders is prepared such that the difference between the sintering shrinkage of each of the first and second feedstocks is less than 1%. The first and second feedstocks are pressed to form a first green part having an enclosure shape and a second green part having a heat sink shape. The lubricants and the binders from said first and second green parts are removed to form a first powdered skeleton and a second powdered skeleton. The first and second powdered skeletons are sintered to complete the combined enclosure and heat sink structure. The first and second powdered skeletons are in intimate contact during the sintering. Optionally, at least one hollow cooling channel is formed in the combine structure by burning away a fugitive plastic structure during the sintering process.
摘要:
The invention shows how powder injection molding may be used to form a continuous body having multiple parts, each of which has different functional properties such as corrosion resistance or hardness, there being no connective materials such as solder or glue between the parts. This is accomplished through careful control of the relative shrinkage rates of these various parts. Although there is no limit to how many parts with different functional properties can make up an object, special attention is paid to certain pairs of functional properties that are difficult and/or expensive to combine in a single object when other manufacturing means are used.
摘要:
Heat dissipation during the operation of integrated circuit chips is an old problem that continues to get worse. The present invention significantly ameliorates this by placing an embedded heat pipe directly beneath the chip. Using powder injection molding, the lower portion of the package is formed first as an initial green part which includes one or more cavities. The latter are then lined with a feedstock that is designed to produce a porous material after sintering, at which time a working fluid is introduced into the porous cavities and sealed, thereby forming one or more heat pipes located directly below the chip. The latter is then sealed inside an enclosure. During operation, heat generated by the chip is efficiently transferred to points outside the enclosure. A process for manufacturing the structure is also described.
摘要:
The invention shows how powder injection molding may be used to form a continuous body having multiple parts, each of which has different physical properties such as magnetic characteristics or hardness. This is accomplished through careful control of the relative shrinkage rates of these various parts. Additionally, care is taken to ensure that only certain selected physical properties are allowed to differ between the parts while others may be altered through relatively small changes in the composition of the feedstocks used. An additional application of the present invention is a process for forming, in a single integrated operation, an object that is contained within an enclosure while not being attached to said enclosure. This is accomplished by causing the shrinkage rate of the object to be substantially greater than that of the enclosure. As a result, after sintering, the object is found to have detached itself from the enclosure and is free to move around therein. Several examples of structures formed using these processes are presented.
摘要:
The invention shows how powder injection molding may be used to form a continuous body having multiple parts, each of which has different functional properties such as corrosion resistance or hardness, there being no connective materials such as solder or glue between the parts. This is accomplished through careful control of the relative shrinkage rates of these various parts. Although there is no limit to how many parts with different functional properties can make up an object, special attention is paid to certain pairs of functional properties that are difficult and/or expensive to combine in a single object when other manufacturing means are used.
摘要:
Heat dissipation during the operation of integrated circuit chips is an old problem that continues to get worse. The present invention significantly ameliorates this by placing an embedded heat pipe directly beneath the chip. Using powder injection molding, the lower portion of the package is formed first as an initial green part which includes one or more cavities. The latter are then lined with a feedstock that is designed to produce a porous material after sintering, at which time a working fluid is introduced into the porous cavities and sealed, thereby forming one or more heat pipes located directly below the chip. The latter is then sealed inside an enclosure. During operation, heat generated by the chip is efficiently transferred to points outside the enclosure. A process for manufacturing the structure is also described.
摘要:
Heat dissipation during the operation of integrated circuit chips is an old problem that continues to get worse. The present invention significantly ameliorates this by placing an embedded heat pipe directly beneath the chip. Using powder injection molding, the lower portion of the package is formed first as an initial green part which includes one or more cavities. The latter are then lined with a feedstock that is designed to produce a porous material after sintering, at which time a working fluid is introduced into the porous cavities and sealed, thereby forming one or more heat pipes located directly below the chip. The latter is then sealed inside an enclosure. During operation, heat generated by the chip is efficiently transferred to points outside the enclosure. A process for manufacturing the structure is also described.
摘要:
This invention describes a novel production method of manufacturing metal/ceramic articles with complex internal undercut features using powder injection molding processes The shape of the undercut/hollow feature is initially molded using a disposable material such as a degradable polymer. The PIM feedstock is then molded onto this to form the required shape geometry, in effect encapsulating the polymeric feature in the PIM feedstock. The resulting two-material part is then sent for processing which removes the polymer through solvent or thermal process. After the polymer and the binder have been removed, the part now comprises a powder skeleton that contains the internal undercut feature within itself. After sintering the result is a metal/ceramic part having an internal undercut feature. The technical advantage of the present invention is that it does not require complex toolings or costly secondary operations while retaining the flexibility to design any internal undercut features of complex geometry. An additional embodiment of the invention is also disclosed in which a solid structure is encapsulated inside a hollow shell said structure being free to move around inside the shell.