RESUMO
Batteries and electrochemical capacitors (ECs) are of critical importance for applications such as electric vehicles, electric grids, and mobile devices. However, the performance of existing battery and EC technologies falls short of meeting the requirements of high energy/high power and long durability for increasing markets such as the automotive industry, aerospace, and grid-storage utilizing renewable energies. Therefore, improving energy storage materials performance metrics is imperative. In the past two decades, radiation has emerged as a new means to modify functionalities in energy storage materials. There exists a common misconception that radiation with energetic ions and electrons will always cause radiation damage to target materials, which might potentially prevent its applications in electrochemical energy storage systems. But in this review, we summarize recent progress in radiation effects on materials for electrochemical energy storage systems to show that radiation can have both beneficial and detrimental effects on various types of energy materials. Prior work suggests that fundamental understanding toward the energy loss mechanisms that govern the resulting microstructure, defect generation, interfacial properties, mechanical properties, and eventual electrochemical properties is critical. We discuss radiation effects in the following categories: (1) defect engineering, (2) interface engineering, (3) radiation-induced degradation, and (4) radiation-assisted synthesis. We analyze the significant trends and provide our perspectives and outlook on current research and future directions in research seeking to harness radiation as a method for enhancing the synthesis and performance of battery materials.
RESUMO
Austenitic stainless steel D9 is a candidate for Generation IV nuclear reactor structural materials due to its enhanced irradiation tolerance and high-temperature creep strength compared to conventional 300-series stainless steels. But, like other austenitic steels, D9 is susceptible to irradiation-induced clustering of Ni and Si, the mechanism for which is not well understood. This study utilizes atom probe tomography (APT) to characterize the chemistry and morphology of Ni-Si nanoclusters in D9 following neutron or proton irradiation to doses ranging from 5-9 displacements per atom (dpa) and temperatures ranging from 430-683 °C. Nanoclusters form only after neutron irradiation and exhibit classical coarsening with increasing dose and temperature. The nanoclusters have Ni3Si stoichiometry in a Ni core-Si shell structure. This core-shell structure provides insight into a potentially unique nucleation and growth mechanism-nanocluster cores may nucleate through local, spinodal-like compositional fluctuations in Ni, with subsequent growth driven by rapid Si diffusion. This study underscores how APT can shed light on an unusual irradiation-induced nanocluster nucleation mechanism active in the ubiquitous class of austenitic stainless steels.
RESUMO
This Data in Brief article presents crystallographic data collected along chloride-induced stress corrosion cracks (CISCC) in a gas tungsten arc welded (GTAW) austenitic stainless steel (AuSS) 304L. The experimental setup involved a welded stainless steel 304L coupon of dimensions 105 mm × 18.5 mm × 3 mm, loaded in a 4-point bending fixture with a maximum tensile stress of 380 MPa. The fixtured specimen was immersed in boiling magnesium chloride (MgCl2) solution until a through-crack was observed on the specimen surface after 17 hours of boiling. The cross-section was subsequently polished, and 37 cracks of interest in the heat affected zone (HAZ) and weld zone (WZ) were selected for crystallographic characterization. Scanning electron microscopy (SEM) based electron backscatter diffraction (EBSD) was used to map the grain orientations along and surrounding each crack path. The obtained orientation imaging microscopy (OIM) datasets were post-processed using EDAX OIM V8 proprietary software to generate inverse pole figures (IPF), image quality (IQ) figures, detector signal (SEM) images, and to determine the Taylor factor and Schmid factor of mapped grains. This dataset can be used to understand CISCC crack initiation, propagation, and termination behaviors, as has been reported in the accompanying original research article. This data article providing the raw EBSD OIM datasets and processed images formatted for accessibility in future studies. This comprehensive EBSD dataset can further be used to extract grain boundary misorientation information; benchmark comparative studies of SCC/CISCC in AuSS and other Fe or Ni alloys; and provide critical validation data on grain morphology, misorientation, and crystallography for GTAW and CISCC models.
RESUMO
Atom probe tomography (APT), a 3D microscopy technique, has great potential to reveal atomic scale compositional variations, such as those associated with irradiation damage. However, obtaining accurate compositional quantification by APT for high bandgap materials is a longstanding challenge, given the sensitivity to field evaporation parameters and inconsistent behaviors across different oxides. This study investigates the influence of APT laser energy and specimen base temperature on compositional accuracy in single crystal thoria (ThO2). ThO2 has a broad range of applications, including advanced nuclear fuels, sensors, lasers and scintillators, electrodes, catalysis, and photonics and optoelectronics. The expected stoichiometry of ThO2 is achieved at APT base temperature of 24 K and laser energy of 100 pJ. To overcome mass resolution limitations associated with significant thermal tails, Bayesian methods are applied to deconvolute ion identity within the mass spectra. This approach affirms that the parameters chosen are appropriate for APT analysis of ThO2.