Table of Content

28 February 2026, Volume 60 Issue 2 Previous Issue   

New Type Power System and the Integrated Energy

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Analysis Methods and Simulation Technology Implementation for Power Secondary Systems in New Power Systems HE Ruiwen, YANG Changxin, XIE Haijun, YANG Shenghui, MOHAMMAD Shahidehpour 2026, 60 (2):  175-185.  doi: 10.16183/j.cnki.jsjtu.2024.092 Abstract ( 97 )   HTML ( 11 )   PDF (4903KB) ( 220 )   Save The stochastic dynamic behavior of power secondary system is opaque and difficult to visualize, which obviously hinders the control of the uncertainties brought by strong dependence on information and communication technologies in new power systems. In this paper, methods for steady-state analysis, static security analysis, and transient analysis of power secondary systems, are proposed for the first time. First, a smart substation secondary system with complex functional descriptions is taken as the research object. A simulation tool for the secondary system of intelligent substations is developed and integrated into general network simulation software, which faithfully simulates the entire process of digital information transmission, flow, and processing in the secondary system. Combined with the device-level simulation tester, system-level path tracking and delay recording technology, scenario-level action characteristic display technology, and simulation acceleration technology proposed in this paper, and taking an actual intelligent substation engineering project as a case study, the steady-state analysis, static security analysis, and transient analysis of the power secondary system are realized under network transmission steady-state scenarios, secondary component (partial) failure scenarios, and circuit breaker failure scenarios. Figures and Tables | References | Supplementary Material | Related Articles | Metrics

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Resilience Enhancement Planning Method of Energy Station in Response to Earthquake Disaster with Data Center Access JIN Wenguang, ZHANG Shenxi, ZHANG Heng, CHENG Haozhong, SHEN Yichen 2026, 60 (2):  186-199.  doi: 10.16183/j.cnki.jsjtu.2024.081 Abstract ( 205 )   HTML ( 20 )   PDF (4766KB) ( 624 )   Save In recent years, frequent occurrences of extreme natural events such as earthquakes have led to a significant increase in the probability of component failures within integrated energy systems, severely impacting the operational security and reliability of integrated energy systems. To address this problem, a resilience enhancement planning model is proposed for interconnected multi-energy stations against seismic hazards with data center integration. Initially, the energy station failures during seismic hazards are modelled, and the potential for energy station resilience enhancement considering the response of data center is analyzed. Subsequently, taking the minimum annual comprehensive cost as the objective function, a planning model for energy station resilience enhancement against earthquake disasters with data center integration is built, which is mainly subjected to the constraints of service quality of the data center and the upper limit of heterogeneous energy cut load of multiple energy stations under earthquake disturbances. Finally, the effectiveness of the proposed planning method is verified based on a modified real-world example, with multi-scenarios configured for comparative analysis. Figures and Tables | References | Related Articles | Metrics

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Power System Expansion Planning Model and Solution Algorithm Based on Load Feasible Region and Reliability Tracking LI Xuan, XIE Kaigui, SHAO Changzheng, HU Bo 2026, 60 (2):  200-210.  doi: 10.16183/j.cnki.jsjtu.2024.048 Abstract ( 163 )   HTML ( 3 )   PDF (1631KB) ( 243 )   Save Power system reliability evaluation is a high-dimensional nonlinear problem, which is difficult to be nested into the power system expansion planning model. This paper proposes a power system expansion planning model and its solution algorithm based on load feasible region model and reliability tracking. First, it proposes an approximate distance model based on load feasible region, which transforms the optimization problem of load shedding calculation required into an equation solving. Based on this, it obtains the analytical expression of reliability sensitivity to components’ capacity and the reliability tracking oriented to capacity. Then, it proposes a reliability-oriented capacity expansion planning model, and a solution algorithm based on reliability tracking and greedy algorithm. The results show that the approximate distance model can effectively reduce the computational complexity of reliability evaluation, while the sensitivity model can accurately reflect the influence of equipment capacity on system reliability, and the capacity expansion planning model and algorithm can achieve optimal system capacity expansion planning results. Figures and Tables | References | Supplementary Material | Related Articles | Metrics

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Collaborative Optimization Scheduling Method for Electric-Gas-Thermal Multi-Energy System Under Energy-Transportation Integration FAN Hong, WEI Xinwu, JIA Qingshan, LUO Jiayi 2026, 60 (2):  211-223.  doi: 10.16183/j.cnki.jsjtu.2024.114 Abstract ( 248 )   HTML ( 4 )   PDF (5343KB) ( 252 )   Save Interaction between energy systems and transportation systems will continue to deepen under the context of the dual carbon goals, leading to a need for collaborative optimization scheduling of multiple energy-transportation systems. Therefore, a collaborative optimization scheduling method for electric-gas-thermal multi-energy systems with energy-transportation integration is proposed. First, traffic vehicles to be scheduled are clustered based on the K-means clustering algorithm fused with density-based spatial clustering of applications with noise (DBSCAN) algorithm and Dijkstra algorithm, and models are established for the road network structure and the energy transfer mode involving vehicle operation and vehicle to network technology. The traffic objects include electric vehicles and natural gas vehicles. Then, on this basis, a bi-level optimization scheduling model is developed with the objectives of minimizing the total system cost and minimizing the total power load fluctuation. Finally, numerical example analysis verifies the effectiveness of the proposed model in reducing system cost, reducing carbon emissions, improving wind-solar absorption capacity, and demonstrating the superiority of multi-energy system scheduling. Figures and Tables | References | Related Articles | Metrics

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Game Optimization Scheduling of Wind-Solar-Hydro-Thermal Power Alliance in Upstream and Downstream Regions of Cascade Hydropower BAI Yunjie, XIE Kaigui, SHAO Changzheng, HU Bo 2026, 60 (2):  224-234.  doi: 10.16183/j.cnki.jsjtu.2024.049 Abstract ( 141 )   HTML ( 3 )   PDF (2201KB) ( 226 )   Save Centralized optimization is widely applied in optimization scheduling of wind-solar-hydro-thermal power in cascade hydropower. However, upstream and downstream regions of cascade hydropower often belong to different interest alliances, which hinders centralized optimization from considering the individual preferences of each alliance in their scheduling decisions. To address this, a game optimization dispatch model is established with the goal of maximizing the interests for both upstream and downstream regions. The downstream region provides a certain proportion of its increased revenue as compensation to the upstream region, which adjusts the scheduling strategy to increase the downstream revenue. This game is modeled as a Stackelberg game, of which the leader is the downstream region that provides compensation and determines the compensation coefficient, and the follower is the upstream region that formulates its scheduling strategy. In the bi-level nested optimization model based on the Stackelberg game, the upstream optimal scheduling model at the lower level considers the downstream optimal scheduling strategy, namely, the lower-level model is also a bi-level optimization problem. Finally, a game optimization scheduling model is constructed based on the three-level optimization model. The results show that this model can ensure the individual interests for both upstream and downstream regions while promoting an overall increase in their combined benefits. Figures and Tables | References | Supplementary Material | Related Articles | Metrics

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Local Control Strategy for Optimal Power Flow in Low-Voltage Distribution Network Based on Robust Stochastic Optimization WANG Rui, BAI Xiaoqing, HUANG Shengquan 2026, 60 (2):  235-245.  doi: 10.16183/j.cnki.jsjtu.2024.066 Abstract ( 300 )   HTML ( 6 )   PDF (3257KB) ( 226 )   Save With the promotion of the “dual carbon” goal and the construction of new power systems, the complexity and uncertainty of power systems have increased dramatically, which brings challenges of high proportion of distributed energy and asymmetric loads, such as voltage overstep and three-phase imbalance to distribution network. To cope with these problems, this paper proposes a local control strategy for optimal power flow (OPF) in low voltage distribution network based on robust stochastic optimization (RSO), which uses a 1-norm Wasserstein distance uncertainty set to describe the output uncertainty of distributed energy resource (DER), and builds a robust stochastic optimization model for three-phase four-wire low-voltage distribution network. This model aims to minimize control costs and network losses, while considering the expected adjustments under worst-case scenarios. Local control strategies for distributed energy are obtained without communication infrastructure by convolutional neural networks training. The simulation results verify the effectiveness and economy of the proposed control strategy. Figures and Tables | References | Related Articles | Metrics

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Short-Term Wind Power Prediction Method Based on Closed-Loop Clustering and Multi-Objective Optimization GUO Qi, YAN Jun, HAO Qianpeng, HAN Dong, YANG Zhihao, YAN Xinyue, ZHANG Haipeng, LI Ran 2026, 60 (2):  246-255.  doi: 10.16183/j.cnki.jsjtu.2024.079 Abstract ( 219 )   HTML ( 2 )   PDF (1826KB) ( 368 )   Save In the field of regional short-term combined forecasting of wind power, although deep learning methods can effectively learn the predictive features of each individual model, they tend to rely heavily on the training data distribution, which results in overfitting when the sample data size is small. Additionally, although clustering methods are used to improve the accuracy of regional-level forecasting, existing methods typically aim to minimize the dissimilarity among wind farms, such as geographic dissimilarity, without considering consistency with the forecasting objectives. To address these issues, this paper proposes a short-term wind power prediction method based on closed-loop clustering and multi-objective optimization. Initially, wind farms are divided into multiple clusters by the closed-loop clustering method. For each cluster, the Bootstrap method is utilized to randomly extract N training subsets with replacement from the original dataset. Subsequently, N convolutional neural networks are trained independently using these subsets. Finally, multi-objective optimization is employed to integrate the prediction results from the N convolutional neural networks. Case studies utilizing wind farm data from Inner Mongolia Autonomous Region, China, demonstrate that the proposed method reduces root mean square error by 33.81% compared with the long short-term memory model, by 24.08% compared with the convolutional neural network-based combined forecasting model, and by 14.05% compared to predictions based on the K-means clustering method. Figures and Tables | References | Related Articles | Metrics

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Fault Location Method for Active Distribution Networks Based on Holographic-Mapping of Time-Frequency Traveling Waves ZENG Jupeng, ZENG Xiangjun, BAI Hao, YU Kun, YANG Weichen, LONG Xuanlin, ZHUANG Jie 2026, 60 (2):  256-269.  doi: 10.16183/j.cnki.jsjtu.2024.063 Abstract ( 164 )   HTML ( 5 )   PDF (6914KB) ( 402 )   Save Some existing fault location methods for distribution networks rely heavily on the local wave head information in the time or frequency domain, resulting in poor location robustness and difficulty in adapting to the increasingly prominent “dual-high” characteristics of active distribution networks. To address this problem, traveling wave time and frequency ranges which can effectively prevent waveform distortion caused by new energy access are analyzed, and the one-to-one holographic-mapping relationship between the traveling wave waveforms in these ranges and the fault positions is revealed. A fault traveling wave time-frequency matrix is constructed based on specific time and frequency windows, and an active distribution network fault location method is proposed based on the holographic-mapping matching technique of waveform features, which realizes the accurate fault location by exploring the proportionality between the cumulative trend of the matrix energy amplitude deviation and the fault point position. Simulation tests and real field model experiments prove that the method effectively overcomes the impact of new energy integration and the complex structure of overhead-cable hybrid lines on fault location, and flexibly transforms the fault location problem into a time-frequency traveling wave holographic-mapping matching problem, which improves the accuracy and robustness of the fault location in active distribution networks. Figures and Tables | References | Related Articles | Metrics

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Impact of Impulse Current on Current Protection in Fault Recovery and Closing of Active Distribution Networks with Soft Open Point YANG Zengli, WANG Ruoqi, HU Yan, FAN Chunju, WANG Jing 2026, 60 (2):  270-276.  doi: 10.16183/j.cnki.jsjtu.2024.194 Abstract ( 225 )   HTML ( 3 )   PDF (961KB) ( 210 )   Save In distribution networks with distributed generation (DG), employing a soft open point (SOP) to replace a tie switch during fault recovery enables load transfer and simultaneous voltage support for distributed generations. However, the bidirectional breaker closure enabled by SOP can induce surge currents when the voltages on the two sides are not aligned, potentially compromising system security if not controlled. This paper treats the phase difference between the SOP-supported voltage during fault recovery and the system power supply voltage as a principal source of the closing surge current, and also accounts for the voltage phase jump at the DG interconnection point. The total closing surge current is expressed as the superposition of two contributing parts with their physical interpretations provided. A simplified formula for the total closing surge current is proposed of which the correctness and reasonableness is validated by time-domain simulations on a standard distribution network model. The impact of the closing surge on system-side current protection is examined and an upper bound on the permissible DG capacity for the network is identified based on a limit analysis of the maximum surge current. The results indicate that over-sized DG capacity may pose a risk of failure in protection actions. Figures and Tables | References | Related Articles | Metrics

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Analysis of Four-Quadrant Control Characteristics and Parameter Design of Inertia Synchronized Three-Phase PWM Converter GUO Ziteng, WANG Han, WANG Fuwen, CAO Yunfeng, ZHANG Jianwen, CAI Xu 2026, 60 (2):  277-288.  doi: 10.16183/j.cnki.jsjtu.2024.094 Abstract ( 189 )   HTML ( 2 )   PDF (6283KB) ( 222 )   Save One of the mainstream schemes for grid-forming control in new energy power generation units is the inertia synchronization control for pulse width modulation (PWM) converters (ISynC-converter). However, existing research primarily focuses on the control characteristics in inverter mode, while studies on its four-quadrant control characteristics and parameter design methods for system control remain insufficient. To address these issues, a linearized model of the ISynC-converter is first established considering the pre-synchronization stage, and the frequency-domain analytical equations for direct current (DC) voltage-phase angle and reactive power-voltage are developed. Then, a design method for key control parameters in the DC voltage loop and reactive power loop is proposed. Finally, the feasibility of the proposed method is verified through simulations and experiments, and the four-quadrant control characteristics as well as inertia support capability are analyzed. The results indicate that the DC voltage and reactive power loops of the ISynC-converter exhibit strong coupling in all four-quadrant operating regions, leading to significant reactive power fluctuations during DC voltage disturbances. Additionally, while the ISynC-converter demonstrates inertia support capability, its effect is limited due to the low inertia contribution of the DC capacitor. These findings provide a foundation for further research on decoupling control between the DC voltage and reactive power loops, as well as strategies to enhance inertia support capabilities. Figures and Tables | References | Related Articles | Metrics

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Performance Degradation Analysis of DMFC Under Different Operating Conditions Based on Relaxation Times WANG Yangda, WANG Jianguo, LIAN Guan, ZHANG Dacheng 2026, 60 (2):  289-299.  doi: 10.16183/j.cnki.jsjtu.2024.110 Abstract ( 249 )   HTML ( 3 )   PDF (4560KB) ( 393 )   Save To investigate the performance degradation characteristics of direct methanol fuel cell (DMFC) under two different operating conditions, the worldwide harmonized light vehicle test cycle (WLTC) and China light vehicle test cycle (CLTC), a combined method of polarization curves, equivalent circuit models, and the distribution of relaxation times (DRT) is adopted to analyze the performance degradation characteristics of DMFC. Using electrochemical impedance spectroscopy, the degradation behavior of DMFC is characterized during the polarization process by calculating the variation in DRT based on the evolution of the waveforms. The results show that the degradation in the WLTC condition is more severe than in the CLTC condition. The obstruction of the mass transfer process resistance plays a dominant role in the performance degradation of DMFC under both operating conditions. The rate of change of the mass transfer process resistance is 2.39 mΩ/h under WLTC and 0.764 mΩ/h under CLTC. Meanwhile, the oxygen reduction reaction resistance is not affected by the operating conditions. The significant dynamic fluctuations and abundant transient states of CLTC operating conditions pose greater hindrance to proton transport, thereby effectively reducing the membrane-bound water content. However, it exerts a minor impact on the mass transfer resistance and promotes an increase in the rate of oxygen diffusion. A fuel cell degradation model is developed to characterize the ageing state of DMFCs based on the distribution of relaxation times hindered by the oxygen reduction reaction, which provides a reference for the health state assessment and optimization in DMFC operation. Figures and Tables | References | Related Articles | Metrics

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Operation Trajectory Planning and Path Power Optimization Control of Electric Quay Crane in Ports LOU Jiahui, HUANG Wentao, YANG Huanhong, YU Moduo, YANG Yayu 2026, 60 (2):  300-310.  doi: 10.16183/j.cnki.jsjtu.2024.097 Abstract ( 204 )   HTML ( 3 )   PDF (6573KB) ( 518 )   Save To address the issues of high peak power demand and low energy conversion efficiency in electric quay cranes at ports, a method for trajectory planning and path power optimization control of electric quay cranes is proposed. The energy coupling conversion relationship and operational characteristics of electric quay cranes are analyzed, from which the dynamic equation is derived. Considering the environmental constraints during the working process of electric quay cranes, a B-spline curve is used to design the operation trajectory of electric quay cranes. The relationship between path power transmission and conversion of electric quay cranes is analyzed, and in combination with the system dynamics, a quantitative description relationship between the operating trajectory and path power is determined, forming an electric quay crane trajectory-power model. The trajectory of electric quay cranes is optimized with the objective of minimizing total electricity consumption, which results in a reduction of path power loss. Simulation examples are established in MATLAB, and the method proposed shows significant improvements in the path power optimization control of electric quay cranes under different working conditions, demonstrating its effectiveness and reliability. Figures and Tables | References | Related Articles | Metrics

Mechanical Engineering

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Thermodynamic Performance Study of an Ammonia-Fueled Microturbine Based on Chemical Recuperation ZHANG Shijie, CHANG Yourun, WANG Aiti 2026, 60 (2):  311-318.  doi: 10.16183/j.cnki.jsjtu.2024.108 Abstract ( 290 )   HTML ( 3 )   PDF (3236KB) ( 497 )   Save This paper develops an ammonia-fueled micro gas turbine cycle based on chemical recuperation. Using energy and exergy analysis methods, it evaluates the overall thermodynamic performance of the cycle, analyzes the reasons for efficiency improvement, and studies the impact of key parameters. The results show that within the parameter range of combustion chamber outlet temperatures of 750—1 050 ℃ and pressure ratios of 3—8, the efficiency of the ammonia-fueled chemical recuperation micro gas turbine cycle can reach 28.8%—41.7%, which is about 1.87—5.61 percentage points higher than that of a methane-fueled micro gas turbine recuperation cycle. The integration of microturbine with chemical recuperation significantly improves efficiency and specific work. The ammonia thermal chemical recuperation system can recover 36%—43% of the exhaust exergy, with the chemical recuperation reactor accounting for more than half of this recovery. The exergy recovery in the chemical recuperator is the fundamental reason for the increased cycle efficiency. The micro gas turbine exhaust can increase the molar ratio of H2 in the ammonia decomposition gas to above 35%, with a maximum of up to 68%, thereby effectively improving the fuel combustion characteristics. For every 10 ℃ increase in the chemical recuperation reaction equilibrium temperature difference, the cycle efficiency decreases by about 0.2 percentage points, thus efficient ammonia decomposition in the thermal chemical recuperation reactor is crucial. Figures and Tables | References | Related Articles | Metrics

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Numerical Simulation Analysis of a Novel Discharge Speed-Regulation Device for Detector in the Pipeline TANG Jian, YU Wenxiu, ZHANG Qiuping, JIAO Xiangdong, DING Xuepeng 2026, 60 (2):  319-330.  doi: 10.16183/j.cnki.jsjtu.2024.225 Abstract ( 171 )   HTML ( 2 )   PDF (2953KB) ( 227 )   Save To address the issue of speed control of in-line detector in oil pipelines, a novel discharge speed-regulation device is proposed, which consists of a relief valve seat, a relief valve core, a spring, a guide rod, and other components. A mathematical model of the discharge speed-regulation device is established by analyzing the force acting on this device in a horizontal pipeline. The influence of the radians of the relief valve seat, the distance between the relief valve core and the back end of the detector, and the inlet fluid velocity on the motion state of the detector in the pipeline is studied using numerical simulation methods. The research results show that under the same boundary conditions, when the fluid passes through the detector, the differential pressure across the discharge speed-regulation device, the total head loss coefficient, and the turbulent kinetic energy of the flow field are inversely proportional to the left radian of the relief valve seat and directly proportional to the right radian. When the left radian of the relief valve seat is 60° and the right radian is 15°, all parameters reach their minimum values. An increase in the inlet fluid velocity will lead to higher pressure differences between the front and back ends of the discharge speed-regulation device, and more turbulent kinetic energy in the flow field. When the radians of the relief valve seat holds constant and the inlet fluid velocity increases from 0.6 m/s to 2 m/s, the differential pressure increases by 106 290 Pa and the turbulent kinetic energy increases by 1.831 m2/s2. The distance between the relief valve core and the back end of the detector is inversely proportional to the pressure difference between the front and back ends of the discharge speed regulation device and the speed of the detector. When the distance between the valve core and the back end of the detector increases from 15 mm to 35 mm, the pressure difference between the front and back ends of the discharge speed regulation device decreases by 240 Pa. This paper provides an important theoretical basis and practical guidance for optimizing the operational performance of in-line detectors in oil pipelines and improving detection efficiency. Figures and Tables | References | Related Articles | Metrics

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Flow-Induced Vibration Response of a Flat Plate in a Confined Rectangular Channel WU Yikai, ZHU Yechen, GONG Shengjie 2026, 60 (2):  331-337.  doi: 10.16183/j.cnki.jsjtu.2024.106 Abstract ( 136 )   HTML ( 2 )   PDF (4145KB) ( 240 )   Save Experiments on flow induced vibration of a rectangular flat plate with two ends fixed in a confined channel are conducted, and vibration response characteristics of the plate are obtained. The results show that the main physical mechanisms of vibration are turbulent-induced vibration and vortex-induced vibration. The turbulence excites the response of the first natural frequency of plate and is amplified with the increasing flow velocity. The frequency of vortex-induced vibration shows a linear increase with the flow velocity, and the Strouhal number Sr=0.24 within the test range. The ‘lock-in’ phenomenon and resonance occur when the vortex shedding frequency approaches the natural frequency, and non-linear frequency-doubling response appears. The first natural frequency of the flat plate shows no obvious trend with changes in flow velocity. In addition, the wet modal analysis based on acoustic-solid coupling method were conducted and the predicted results show a good agreement with the experimental values. Figures and Tables | References | Related Articles | Metrics

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Simulation and Experiments on Fabrication of Strain Controllable Aluminum Strips by Stepped Rake Angle Tool ZHONG Peixuan, ZHANG Baoyu, LI Songqing, SHEN Pengyu, DENG Wenjun 2026, 60 (2):  338-348.  doi: 10.16183/j.cnki.jsjtu.2024.107 Abstract ( 153 )   HTML ( 2 )   PDF (28101KB) ( 226 )   Save The reduction of the tool rake angle in the extrusion machining process is conducive to increase the shear strain and grain refinement, but it easily leads to problems such as strip extrusion difficulties and poor surface quality. To improve the forming quality of ultrafine-grained aluminum strips and to realize the controllable strain distribution adjustment, a new process of extrusion machining with a stepped rake angle tool is proposed. By combining simulation and experiments, the strip morphology, microhardness, and microstructure of 6061 aluminum alloy under different machining parameters are investigated. Extrusion machining with conventional rake angle tool is also conducted as a comparative test. The results show that the stepped rake angle tool achieves the continuous formation of ultrafine-grained strip with different strain distributions within the strip, and the ratio of high and low strain zones is adjustable by changing the cutting thickness. This process can provide ideas and methods for tool design and ultrafine-grain material preparation. Figures and Tables | References | Related Articles | Metrics