Licensable Technology
Inventions Resulting from Penn State Energy Research
Method and Device to Manufacture Camber Free Multilayer Ceramics During Co-sintering
By Sang-Ho Lee and Gary L. Messing
Penn State Invention Disclosure No. 2003-2749
Co-sintering of multilayer laminates is usually accompanied by camber and/or cracking because of mismatch in the sintering shrinkage of the individual layers. Normally, the amount of the total shrinkage and the shrinkage profile vs. temperature should be matched if camber and/or cracking are to be avoided. However, it is nearly impossible to match the sintering shrinkage behavior. The mismatch in densification profiles causes camber during co-sintering of heterogeneous laminated layer, if it is in asymmetric shape, or delamination if it is in symmetric shape. Careful shrinkage control is especially required for alumina packages or Multilayer Ceramic Structures, which have become increasingly important in the electronic ceramic industry.
This invention relates to a method and device for making a multilayer laminate ceramic structure camber-free. The main advantage of this invention over previous technologies is that camber free laminate can be co-sintered by using the invention’s novel, inexpensive loading system.
This invention can be applied specifically to planar type Solid Oxide Fuel Cell-related technology in which an anode/electrolyte/cathode multilayer must be co-sintered without camber. Due to the warpage and mechanical strength problem, the anode or cathode thicknesses are currently quite thick to avoid the warpage problem. Producing warpage-free, co-sintered planar type fuel cells is a critical manufacturing issue, especially when the thickness of the individual layers is very thin. Application of this technology may be of particular interest to companies participating in the Solid State Energy Conversion Alliance (SECA) program1) in order to optimize performance of the solid oxide fuel cell by using thinner layers.
The researchers have demonstrated the co-sintering of thin (<200 microns) planar type solid oxide fuel cells without camber. The inventors have successfully produced multilayer laminates composed of LaSrMnO3/ZrO2/NiO-ZrO2 system, which is a typical layer structure of a SOFC. The researchers believe that this invention will allow the production of multilayer ceramics with a thickness as small as 30 microns.
1) Mark C. Williams, “Status and Market Application for the Solid Oxide Fuel Cell in the U.S.-a New Direction,” pp. 3-7 in Proceedings of Solid Oxide Fuel Cell VII, Electrochemical Society Proceeding Volume 2001-16, 2001.
Contact
Matthew D. Smith
Intellectual Property Office
mds126@psu.edu