Jiacheng Zhang, Mao Zhang, Lei Deng, Junsong Jin, Pan Gong, Xuefeng Tang, Xinyun Wang
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引用次数: 0
Abstract
Stress-induced FCC-BCC phase transformation plays a crucial role in the mechanical behaviors of high-entropy alloys (HEAs). While there has been extensive research on this transformation during monotonic deformation, studies on fatigue behavior are extremely limited. Here, we use molecular dynamics simulations to investigate phase transformation and dislocation evolution in HEAs under strain-controlled symmetric tension–compression cycles. Our results show that cyclic deformation behavior is sensitive to strain amplitude, revealing three distinct cyclic responses. Notably, a progressive FCC-BCC phase transformation process occurs at a high strain amplitude of 4.8%. Grain boundaries and their triple junctions are identified as preferred sites for phase transformation under cyclic loading conditions. These findings provide valuable atomic-scale insights for understanding fatigue deformation in HEAs with transformation-induced plasticity.
期刊介绍:
Materials Letters has an open access mirror journal Materials Letters: X, sharing the same aims and scope, editorial team, submission system and rigorous peer review.
Materials Letters is dedicated to publishing novel, cutting edge reports of broad interest to the materials community. The journal provides a forum for materials scientists and engineers, physicists, and chemists to rapidly communicate on the most important topics in the field of materials.
Contributions include, but are not limited to, a variety of topics such as:
• Materials - Metals and alloys, amorphous solids, ceramics, composites, polymers, semiconductors
• Applications - Structural, opto-electronic, magnetic, medical, MEMS, sensors, smart
• Characterization - Analytical, microscopy, scanning probes, nanoscopic, optical, electrical, magnetic, acoustic, spectroscopic, diffraction
• Novel Materials - Micro and nanostructures (nanowires, nanotubes, nanoparticles), nanocomposites, thin films, superlattices, quantum dots.
• Processing - Crystal growth, thin film processing, sol-gel processing, mechanical processing, assembly, nanocrystalline processing.
• Properties - Mechanical, magnetic, optical, electrical, ferroelectric, thermal, interfacial, transport, thermodynamic
• Synthesis - Quenching, solid state, solidification, solution synthesis, vapor deposition, high pressure, explosive