Sequential Component Manufacturing
In order to integrate additional functionalities within one component, different materials or material mixtures have to be combined. This poses an enormous challenge in thermal co-processing, making optimization of the debinding and sintering steps critical.
Overview
The difference between materials' coefficients of thermal expansion (CTE) may lead to the creation of large stresses during the cooling stage of sintering and thus to the formation of cracks. One way to mitigate this is to use two different thermal processing steps, each used and optimized for the different materials which should be combined.
First, one material is shaped and sintered before the second material is applied to the sintered surface of the first material and also sintered in a second thermal process at a lower temperature. This manufacturing strategy is called sequential manufacturing.
Because no co-sintering is necessary a broad portfolio of realizable material combinations exists and established, highly productive thick film technologies with high resolution (e.g. screen printing) can be used for application of 2nd material.
But the deposition of the functional materials is only possible on accessible surfaces. A further limitation is that the geometry and quality of the surface of 1st material must meet the requirements of the deposition technology for the 2nd material and two thermal processing are necessary.