What is the purpose of copper infiltration into a PM component, and how is it accomplished?
Here's how copper infiltration works:
The base structure of the component has a known density, which is used to determine the amount of open porosity. A measured amount of copper is selected matching the amount of porosity to be filled. The copper fills the porosity during the sintering process (at temperatures above the melt temperature of copper) simply by placing the copper against the component prior to sintering. The >2000°F sintering temperature allows for the molten copper to flow into the component porosity through capillary action. Sintering is completed on a carrier (e.g. ceramic plate) so the copper stays on the component. Once the part is cooled, the copper is solidified within the structure.