When studying extremely fast reactions in ultrathin materials, two measurements are better than one. A new research tool invented by researchers at Lawrence Livermore National Laboratory (LLNL), Johns Hopkins University and the National Institute of Standards and Technology (NIST) captures information about both temperature and crystal structure during extremely fast reactions in thin-film materials.More
Michael Grapes Selected as Finalist for MRS Graduate Student Awards
Congratulations to Michael Grapes, a graduate student researcher in Professor Tim Weihs’ group, who was selected as a finalist for the MRS graduate student awards! At the 2014 MRS Spring Meeting, Michael will present a talk titled In situ nanocalorimetry with time-resolved electron microscopy for the study of rapid phase transformations.
“I’ll be describing a system I’ve developed that combines very fast thermal analysis using a technique called ‘nanocalorimetry’ with a very fast electron microscope known as the ‘dynamic transmission electron microscope’ or DTEM. This development allows us to simultaneously measure the heat output and the structural changes that occur in reactive samples when they are heated at high rates,” Michael said.
Though applicable to a wide range of materials, this system was developed specifically due to an interest in reactive materials. The interfacial reactions between the layers of multilayered reactive materials is connected to both the temperature and concentration gradient, which influences the energy benefit of the reaction.
“By varying the heating rate as we can with the nanocalorimeter, the temperature and concentration gradient are decoupled allowing us to study their effects independently. Since we expect those effects to be on the phases that form at the interface, we needed a way to identify what happens to the sample as we heat very quickly. That’s where the DTEM came in, leading us to develop the whole system.”
Ultimately, Mike’s hope is that people who hear his talk will see a use for this system in their own research so that in situ nanocalorimetry can be a general tool available to many researchers.