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CAREER: High Temperature Deformation of Stand-Alone Plasma-Sprayed 7 wt.% Y 2 O 3 -ZrO 2. Rodney W. Trice, Purdue University, DMR 0134286.
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CAREER: High Temperature Deformation of Stand-Alone Plasma-Sprayed 7 wt.% Y2O3-ZrO2 Rodney W. Trice, Purdue University, DMR 0134286 Intellectual Merit: Thermal barrier coatings (TBCs) like 7 wt.% Y2O3-ZrO2 (YSZ) are used to protect blades and other hot structures in gas turbine engines. These coatings play a critical role in the transportation and energy sectors of the U.S. economy by improving engine efficiency and conserving fuel. Our research links the insulating properties of these coatings to their characteristic features or microstructures. This year we found that the way in which TBCs are put into service affects how well they insulate the gas turbine engine. For example, a coating that is under stress at elevated temperatures has a fundamentally different ability to protect the gas turbine than a coating that is not stressed, but exposed to the same temperature. The adjacent plot shows how thermal conductivity is affected by temperature and stress exposure. For a TBC, we desire the lowest thermal conductivity. The coating that was heated (3 hours, 1200oC) under stress (60 MPa) is significantly less insulative than the one that was simply heated for the identical time and temperature. Investigations of the microstructure linked the increase in thermal conductivity to stress-assisted closure of the cracks in the coating.
CAREER: High Temperature Deformation of Stand-Alone Plasma-Sprayed 7 wt.% Y2O3-ZrO2 Rodney W. Trice, Purdue University, DMR 0134286 Broader Impacts: Eric Jones, a sophomore high school student at nearby Jefferson High School in Lafayette, IN, has been supported by this grant. This past year he investigated the effect of CMAS hot corrosion on the phase stability of 7 wt.% Y2O3-ZrO2 (YSZ), a common thermal barrier coating material (TBC). CMAS is composed of CaO, MgO, Al2O3, and SiO2 and is essentially sand that is ingested into the gas turbine. Once ingested, it melts and infiltrates the coating, greatly damaging the YSZ thermal barrier coating. His results were presented at a regional science fair in April, 2007. The larger photograph shows his poster; the inset shows Eric with the Great Lakes Chemical Outstanding Project in Chemistry trophy,one of the 4 awards he garnered for his work on this project.