42 citations · 144 across the 22 of their papers we have counts for
22 papers
Influence of dislocation density on the tribological response in oxides: case study on SrTiO3
Chukwudalu Okafor, Oliver Preuß, Thomas Chudoba +6
Most ceramics suffer from brittle surface damage and cracking when small particles slide across the surface under low load. Microscratching tests are a useful technique to mimic th…
A solid-solution approach for room-temperature bulk plasticity in KTa1-xNbxO3
Alexander Frisch, Jiawen Zhang, Martin Setvin +3
Dislocations are being engineered into perovskite oxides to harvest versatile functional properties. One major bottleneck, however, persists: perovskite oxides that can be engineer…
Oxygen Vacancies at Dislocation Core Modulate Plasticity in Strontium Titanate
Min-Chul Kang, Chunxu Yan, Alexander Frisch +3
Dislocation core chemistry in oxides critically influences mechanical behavior and functionality; yet the evolution of core chemistry during the dislocation motion in them has not…
Tunable dislocations overcome mechano-functional tradeoff in perovskite oxides
Jiawen Zhang, Wenjun Lu, Xufei Fang
Recent advancements in dislocation engineering are reshaping the traditional view towards ceramics being brittle. Here, we use KTaO3 (KTO), a perovskite oxide that is newly discove…
A data-driven quest for room-temperature bulk plastically deformable ceramics
Iwo Słodczyk, Alexander Frisch, Xufei Fang +2
The growing number of ceramics exhibiting bulk plasticity at room temperature has renewed interest in revisiting plastic deformation and dislocation-mediated mechanical and functio…
Scale-bridging dislocation plasticity in MgO at room temperature
Jiawen Zhang, Zhangtao Li, Yuwei Zhang +7
Dislocations in ceramics have recently gained renewed research interest, in contrast to the traditional belief that ceramics are inherently brittle. Understanding dislocation mecha…
Dislocation-point defect interaction on plasticity across the length scale in SrTiO3
Chukwudalu Okafor, Kohei Takahara, Svetlana Korneychuk +7
Point defect engineering is widely used to tailor the electronic and transport properties of complex oxides, yet its influence on dislocation plasticity remains poorly understood.…
Dislocation response to electric fields in strontium titanate: A mesoscale indentation study
Alexander Frisch, Daniel Isaia, Oliver Preuß +1
Dislocations in perovskite oxides have drawn increasing research interest due to their potential of tuning functional properties of electroceramics. Open questions remain regarding…
Dislocation interaction with a tilt low angle grain boundary in bi-crystal SrTiO3
Kuan Ding, Atsutomo Nakamura, Patrick Cordier +1
For potentially wider applications of ceramics with dislocation-tuned mechanical and functional properties, it is pertinent to achieve dislocation engineering in polycrystalline ce…
Toughening beta-Ga2O3 via mechanically seeded dislocations
Zanlin Cheng, Jiawen Zhang, Peng Gao +3
\b{eta}-Ga2O3 is a promising candidate for next-generation semiconductors, but is limited by its intrinsic brittleness, which hinders its application in flexible electronics and hi…
Stable crack propagation in dislocation-engineered oxide visualized by double cleavage drilled compression test
Oliver Preuß, Zhangtao Li, Enrico Bruder +4
Understanding crack tip - dislocation interaction is critical for improving the fracture resistance of semi-brittle materials like room-temperature plastically deformable ceramics.…
Dislocation-enhanced piezoelectric catalysis of KNbO3 crystal for water splitting
Hanyu Gong, Jiawen Zhang, Yan Zhao +6
Dislocations in oxides with ionic/covalent bonding hold the potential of harnessing versatile functionalities. Here, high-density dislocations in a large plastic zone in potassium…
Dislocation Engineering: A New Key to Enhancing Ceramic Performances
Haoxuan Wang, Yifan Wang, Xu Liang +3
Dislocations are line defects in crystalline solids and often exert a significant influence on the mechanical properties of metals. Recently, there has been a growing interest in u…
Hydrogen response to high-density dislocations in bulk perovskite oxide SrTiO3
Xufei Fang, Lars Dörrer, Svetlana Korneychuk +6
Hydrogen plays an increasingly important role in green energy technologies. For instance, proton-conducting oxides with high performance for fuel cell components or electrolysers n…
Room-temperature dislocation plasticity in ceramics: Methods, Materials, and Mechanisms
Alexander Frisch, Chukwudalu Okafor, Oliver Preuß +5
Dislocation-mediated plastic deformation in ceramic materials has sparked renewed research interest due to the technological potential of dislocations. Despite the long research hi…
Impact of dislocation densities on the microscale strength of single-crystal strontium titanate
Jiawen Zhang, Xufei Fang, Wenjun Lu
Dislocations in ceramics at room temperature are attracting increasing research interest. Dislocations may bring a new perspective for tuning physical and mechanical properties in…
Coupled electromigration-nanoindentation study on dislocation nucleation in SrTiO3
Chukwudalu Okafor, Ahmad Sayyadi-Shahraki, Sebastian Bruns +5
Modern functional oxides are mainly engineered by doping, essentially by tuning the defect chemistry. Recent studies suggest that dislocations offer a new perspective for enhancing…
Effective reduction in thermal conductivity by high-density dislocations in SrTiO3
Jinxue Ding, Jiawen Zhang, Jinfeng Dong +5
Decreasing thermal conductivity is important for designing efficient thermoelectric devices. Traditional engineering strategies have focused on point defects and interface design.…
Dislocations and plasticity of KTaO perovskite modeled with a new interatomic potential
Pierre Hirel, Franck Junior Kakdeu Yewou, Jiawen Zhang +3
Potassium tantalate KTaO3 is a cubic, paraelectric perovskite ceramic that exhibits surprising ductility at room temperature as most recently reported. Much like strontium titanate…
Damage-tolerant oxides by imprint of an ultra-high dislocation density
Oliver Preuß, Enrico Bruder, Jiawen Zhang +3
Dislocations in ductile ceramics offer the potential for robust mechanical performance while unlocking versatile functional properties. Previous studies have been limited by small…
Harvesting room-temperature plasticity in ceramics by mechanically seeded dislocations
Xufei Fang, Wenjun Lu, Jiawen Zhang +7
The quest for room-temperature ductile ceramics has been repeatedly fueled by hopes for large-scale applications but so far has been not successful. Recent demonstrations of enhanc…
Room-temperature bulk plasticity and tunable dislocation densities in KTaO3
Xufei Fang, Jiawen Zhang, Alexander Frisch +4
We report room-temperature bulk plasticity mediated by dislocations in single-crystal cubic KTaO3, contrasting the conventional knowledge that single-crystal KTaO3 is susceptible t…