MIM PROCESS OVERVIEW
MATERIAL: FEEDSTOCK
The MIM process starts with the feedstock which is a powdered material composed of metal and thermoplastic binders that will be extruded in the injection machine
INJECTION
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The feedstock is injected into the mold cavities in the injection molding machine
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The molded part is called green part
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A green part is about 20% bigger than the final product
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Runners and gates are recycled minimizing material waste
DEBINDING
At this stage the feedstock binder is virtually eliminated.
We use two different binder systems PP wax and Poliacetal/Poliolefina.
After the debinding process ends, the part is described as the “brown part”.
We use two different binder systems PP wax and Poliacetal/Poliolefina.
After the debinding process ends, the part is described as the “brown part”.
SINTERING
The part is heated to a temperature below the melting point. The atoms in the powder particles diffuse across the boundaries of the particles, fusing the particles together and creating one solid piece. Because the sintering temperature does not have to reach the melting point of the material, sintering is chosen as the shaping process for materials with high melting points.
AFTER SINTERING PROCESSES
SECONDARY OPERATIONS
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A sintered part is a metal part ready for any secondary operations needed to get dimensions in tolerance not attained during the sintering process: Grinding, coining, machining, tapping or others.
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Sintered parts can be heat-treated as specified in technical documentation.
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Surface treatments such as black oxide and plating are also applicable after sintering.