Through the innovative integration of semi-solid rheo-casting with extrusion shear process,the short-process fabrication of low-alloyed wrought Mg-2Zn-1Mn alloy is achieved in this study.Uniaxial tensile testing of lo...Through the innovative integration of semi-solid rheo-casting with extrusion shear process,the short-process fabrication of low-alloyed wrought Mg-2Zn-1Mn alloy is achieved in this study.Uniaxial tensile testing of low-temperature extrusion shear specimens(200℃)demonstrates the exceptional strength-ductility synergy,yield strength of 277 MPa,yield strength ratio of 0.95,and elongation of 24%.Microstructural observations reveal the mechanisms underlying its high strength-plasticity synergy at room temperature.This study investigates the effects of different temperature gradients on the microstructure by analyzing experiments conducted at three temperatures:300℃,250℃,and 200◦C.Ultimately,the formation mechanism of the bimodal microstructure obtained at 200℃ is elucidated.The distinctive crystallographic texture oriented at 34°relative to the loading axis direction effectively mitigates stress concentration by inducing the synergistic activation of multiple slip systems.Furthermore,the transition trends of different slip systems and texture evolution during tensile deformation are validated through Visco-Plastic Self-Consistent(VPSC)simulations and corroborated by microstructural analysis.With geometrically necessary dislocation(GND)density(4.28×10^(15)m^(-2))and pyramidal slip activation(~45%).This study has successfully broken through the bottleneck of strength-ductility trade-off in magnesium alloys,providing theoretical support for the development of high-reliability magnesium alloys.展开更多
为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根...为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根据车轮运动学和整车运动学建立智能体的滑转率模型;然后,设计了基于多智能体的分布式模型预测控制策略,以多约束条件下的协同优化为目标函数,实现驱动防滑,在解决驱动力不足问题的同时,达到了低能耗和舒适性;最后,利用Simulink软件和CarSim软件进行仿真实验,实验结果证明了所提控制策略的有效性,为分布式驱动的进一步应用提供了新的控制方法。展开更多
基金the financial support from Basic Research Projects of Higher Education Institutions of Liaoning Province(Key Research Projects)(No.JYTZD2023108)General Project of Liaoning Provincial Department of Education(Nos.LJKMZ20220462 and JYTMS20231199).
文摘Through the innovative integration of semi-solid rheo-casting with extrusion shear process,the short-process fabrication of low-alloyed wrought Mg-2Zn-1Mn alloy is achieved in this study.Uniaxial tensile testing of low-temperature extrusion shear specimens(200℃)demonstrates the exceptional strength-ductility synergy,yield strength of 277 MPa,yield strength ratio of 0.95,and elongation of 24%.Microstructural observations reveal the mechanisms underlying its high strength-plasticity synergy at room temperature.This study investigates the effects of different temperature gradients on the microstructure by analyzing experiments conducted at three temperatures:300℃,250℃,and 200◦C.Ultimately,the formation mechanism of the bimodal microstructure obtained at 200℃ is elucidated.The distinctive crystallographic texture oriented at 34°relative to the loading axis direction effectively mitigates stress concentration by inducing the synergistic activation of multiple slip systems.Furthermore,the transition trends of different slip systems and texture evolution during tensile deformation are validated through Visco-Plastic Self-Consistent(VPSC)simulations and corroborated by microstructural analysis.With geometrically necessary dislocation(GND)density(4.28×10^(15)m^(-2))and pyramidal slip activation(~45%).This study has successfully broken through the bottleneck of strength-ductility trade-off in magnesium alloys,providing theoretical support for the development of high-reliability magnesium alloys.
文摘为解决复杂工况下分布式驱动电车(Distributed Drive Electric Vehicle,DDEV)的驱动防滑问题,基于模块化提出了一种多智能体分布式协同控制策略。首先,采用模块化的方法搭建了整车结构,将各轮毂电机车轮和控制器整体视为一个智能体,根据车轮运动学和整车运动学建立智能体的滑转率模型;然后,设计了基于多智能体的分布式模型预测控制策略,以多约束条件下的协同优化为目标函数,实现驱动防滑,在解决驱动力不足问题的同时,达到了低能耗和舒适性;最后,利用Simulink软件和CarSim软件进行仿真实验,实验结果证明了所提控制策略的有效性,为分布式驱动的进一步应用提供了新的控制方法。
