Researchers have demonstrated a new method for testing microscopic aeronautical materials at ultra-high temperatures. By combining electron microscopy and laser heating, scientists can evaluate these materials much more quickly and inexpensively than with traditional testing.
A decade ago, advancements in aeronautical materials involved testing large, expensive models and years of development. Scientists and engineers now use microscale experimentation to help create new materials and understand the chemical and physical properties that lead to material failure. Until now, researchers have been unable to conduct successful microscale materials tests at the extreme temperatures experienced by critical components during flight; specifically, at temperatures above 1000 °C.
This temperature barrier has slowed the development of new materials for commercial applications such as rockets and vehicles that require testing at temperatures well above the current limit of a few hundred degrees Celsius. The new method will significantly reduce the time and expense involved in making these tests possible.
The ultra-high-temperature test combined two commonly used tools. Using a transmission electron microscope and targeted laser heating, the team was able to see and control where and how the material deformed at the highest temperature possible before the sample evaporated.
The test allows growth of a thin film of the material without any special processing and then puts it in the microscope to test a number of different mechanical properties. As proof of concept, the study tested zirconium dioxide — used in fuel cells and thermal barrier coatings — at temperatures up to 2,050 °C, a temperature well above anything that could be done previously.