Research on magnesium alloys continues to attract great attention,with more than 3000 papers on magnesium and magnesium alloys published and indexed in SCI in 2020 alone.The results of bibliometric analyses show that ...Research on magnesium alloys continues to attract great attention,with more than 3000 papers on magnesium and magnesium alloys published and indexed in SCI in 2020 alone.The results of bibliometric analyses show that microstructure control and mechanical properties of Mg alloys are continuously the main research focus,and the corrosion and protection of Mg alloys are still widely concerned.The emerging research hot spots are mainly on functional magnesium materials,such as Mg ion batteries,hydrogen storage Mg materials,and bio-magnesium alloys.Great contributions to the research and development of magnesium alloys in 2020 have been made by Chongqing University,Chinese Academy of Sciences,Central South University,Shanghai Jiaotong University,Northeastern University,Helmholtz Zentrum Geesthacht,etc.The directions for future research are suggested,including:1)the synergistic control of microstructures to achieve high-performance magnesium alloys with concurrent high strength and superior plasticity along with high corrosion resistance and low cost;2)further development of functional magnesium materials such as Mg batteries,hydrogen storage Mg materials,structural-functional materials and bio-magnesium materials;3)studies on the effective corrosion protection and control of degradation rate of magnesium alloys;4)further improvement of advanced processing technology on Mg alloys.展开更多
Higher strength is always the goal pursued by researchers for the structural materials,especially for the lightweight magnesium(Mg)alloys which generally have relatively low strength at present.From this aspect,the pr...Higher strength is always the goal pursued by researchers for the structural materials,especially for the lightweight magnesium(Mg)alloys which generally have relatively low strength at present.From this aspect,the present paper reviews the recent reports of a kind of Mg alloys,i.e.Mg-RE(RE:rare earths,mainly Gd or Y)casting and wrought alloys,which have been able to achieve high strength compared with common or commercial Mg alloys,from the viewpoint and content of the alloy system,alloying constitution,preparation process,tensile strength and each of the main strengthening mechanisms.This review of recent research and developments in high-strength Mg-RE alloys is beneficial for the further design of Mg alloys with higher strength as well as excellent comprehensive performance.展开更多
China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and m...China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and materials scientists over the past decades. Nowadays, a large number of young-generation researchers have been inspired by their predecessors and become the key participants in the fields of Mg alloys, which consequently led to the establishment of China Youth Scholar Society for Magnesium Alloys Research in 2015. Since then, the first two China Youth Scholars Symposiums on Mg Alloys Research had been held at Harbin （2015） and Chongqing （2016） China, respectively. A number of crucial research inter- ests related to fundamental and applied Mg research were discussed at the conferences and summarized in this short perspective, aiming to boost far-reaching initiatives for development of new Mg-based materials to satisfy the requirements for a broad range of industrial employments. Herein, four main aspects are included as follows： i） Plastic deformation mechanism and strengthening strategy, ii） Design and development of new Mg-based materials, iii） Key service properties, and iv） New processing technologies.展开更多
Grain refinement could effectively enhance yield strength of Mg alloys according to the well-known Hall-Petch theory. For decades, many studies have been devoted to the factors influencing the Hall- Petch slope （k） ...Grain refinement could effectively enhance yield strength of Mg alloys according to the well-known Hall-Petch theory. For decades, many studies have been devoted to the factors influencing the Hall- Petch slope （k） in Mg alloys. Understanding the factors influencing k and their mechanisms could offer guidance to design and produce high-strength Mg alloys through effective grain refinement hardening. A review and comments of the past work on the factors influencing k in Mg alloys are presented. Results of these previous investigations demonstrate that the value of k in Mg alloys varies with texture, grain size, temperature and stain. The influence of texture and grain size on k is found to be an essential result of the variation of deformation mode on k value. Without the variation of deformation modes, it is revealed that texture could also impose a significant effect on k and this is also summarized and discussed in this paper. The reason for texture effect on k is analyzed based on the mechanism of Hall-Petch relationship. In addition, it is found in face-centered cubic （fcc） or body-centered cubic （bcc） metals that boundary parameters （boundary coherence, boundary energy and boundary diffusivity） could strengthen twinning or slips to a different extent. Therefore, the role of boundary parameters is also extended into the k values in Mg alloys and discussed in this paper. In the end, we discuss the future research perspective of Hall-Petch relationship in Mg alloys.展开更多
以‘宁粳2号’为材料，采用田间小区试验方法研究了单季粳稻施用镁肥后对镁吸收分配的影响。结果表明，从拔节到始穗期，水稻体内镁的阶段吸收量和吸收速度最高，分别为7．22kg·hm^-2和0．40kg·hm^-2·d^-1；从拔节期到...以‘宁粳2号’为材料，采用田间小区试验方法研究了单季粳稻施用镁肥后对镁吸收分配的影响。结果表明，从拔节到始穗期，水稻体内镁的阶段吸收量和吸收速度最高，分别为7．22kg·hm^-2和0．40kg·hm^-2·d^-1；从拔节期到齐穗期，镁肥的施用促进了水稻对镁的吸收，其它生育期对外界镁浓度变化不敏感；镁肥的施用降低了镁在茎鞘和叶片中的分配比例，提高了镁在穗部的分配比例；齐穗后15～30d为穗部积累镁的高峰期；在本实验范围内，随施肥水平的提高，稻米中的镁含量升高，RVA（Rapid of viscosity analysis）谱中最终黏度、回复值及消减值显著下降，最高黏度、热浆黏度和崩解值显著上升，糊化温度没有明显差异。施用镁肥提高了稻米食味品质，这其中以120kg·hm^-2用量效果最好。展开更多
More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties...More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.展开更多
Magnesium(Mg)alloys have received an increasing interest in the past two decades for their tremendous application potential.The strength and corrosion resistance levels of common Mg alloys are still relativity low,and...Magnesium(Mg)alloys have received an increasing interest in the past two decades for their tremendous application potential.The strength and corrosion resistance levels of common Mg alloys are still relativity low,and especially they are to be improved simultaneously.The addition of rare earth(RE)to Mg alloys is believed to be beneficial for both the strength and corrosion resistance,and some RE-modified traditional Mg alloys have been studied and some new RE-containing Mg alloys have been developed by now.However,further simultaneous improvements in both strength and anti-corrosion require a better understanding of the behavior and mechanism of RE in Mg alloys.In this review,the common influence mechanisms of RE on mechanical and anti-corrosion properties of Mg alloys are summarized,and the latest research progress of RE-containing Mg alloys with simultaneously improved strength and corrosion resistance are introduced.It is demonstrated that the research on high-strength and high corrosion resistant RE-containing Mg alloys is still immature,and some opinions and suggestions are put forward for the synergetic improvement of the strength and corrosion resistance of Mg alloys,so as to contribute to the further development of Mg alloys with higher performance.展开更多
This paper dealt with the effects of Pb 2+,Cd 2+ and their combined pollution on the contents of chlorophyll,potassium and calcium in Thuidium cymbifolium.The results showed that except at 0.1 mg Cd 2+·L -1,the c...This paper dealt with the effects of Pb 2+,Cd 2+ and their combined pollution on the contents of chlorophyll,potassium and calcium in Thuidium cymbifolium.The results showed that except at 0.1 mg Cd 2+·L -1,the chlorophyll content decreased with increasing Pb 2+ and Cd 2+ concentrations,which was 18% of the control at 100 mg Cd 2+·L -1,and decreased by 48.6% at 200 mg Pb 2+·L -1.The potassium and calcium contents also decreased with increasing pollutants concentrations,being decreased by 61.1% at 100 mg Cd 2+·L -1.Cd 2+ had a stronger toxicity than Pb 2+,and the toxicity of their combined pollution was stronger than that of each pollutant.Pb 2+ could increase the toxicity of Cd 2+.展开更多
基金financially supported by the National Key Research and Development Program of China(Project No.2016YFB0301100&Project No.2016YFB0700403)the Chongqing Academician Special Fund(Project No.cstc2018jcyj-yszx X0007&Project No.cstc2020yszx-jcyj X0001)+1 种基金Chongqing Research Program of Basic Research and Frontier Technology(Project No.cstc2019jcyj-msxm0438)the 111 Project(Project No.B16007)by the Ministry of Education and the State Administration of Foreign Experts Affairs of China。
文摘Research on magnesium alloys continues to attract great attention,with more than 3000 papers on magnesium and magnesium alloys published and indexed in SCI in 2020 alone.The results of bibliometric analyses show that microstructure control and mechanical properties of Mg alloys are continuously the main research focus,and the corrosion and protection of Mg alloys are still widely concerned.The emerging research hot spots are mainly on functional magnesium materials,such as Mg ion batteries,hydrogen storage Mg materials,and bio-magnesium alloys.Great contributions to the research and development of magnesium alloys in 2020 have been made by Chongqing University,Chinese Academy of Sciences,Central South University,Shanghai Jiaotong University,Northeastern University,Helmholtz Zentrum Geesthacht,etc.The directions for future research are suggested,including:1)the synergistic control of microstructures to achieve high-performance magnesium alloys with concurrent high strength and superior plasticity along with high corrosion resistance and low cost;2)further development of functional magnesium materials such as Mg batteries,hydrogen storage Mg materials,structural-functional materials and bio-magnesium materials;3)studies on the effective corrosion protection and control of degradation rate of magnesium alloys;4)further improvement of advanced processing technology on Mg alloys.
基金supported by Natural Science Foundation of Heilongjiang Province of China(E2017030,ZD2017010)National Natural Science Foundation of China(51671063,51771060,51871069)+1 种基金Fundamental Research Funds for the Central Universities(HEUCFM181002)Foundation of State Key Laboratory of Rare Earth Resources Utilization(RERU2018017).
文摘Higher strength is always the goal pursued by researchers for the structural materials,especially for the lightweight magnesium(Mg)alloys which generally have relatively low strength at present.From this aspect,the present paper reviews the recent reports of a kind of Mg alloys,i.e.Mg-RE(RE:rare earths,mainly Gd or Y)casting and wrought alloys,which have been able to achieve high strength compared with common or commercial Mg alloys,from the viewpoint and content of the alloy system,alloying constitution,preparation process,tensile strength and each of the main strengthening mechanisms.This review of recent research and developments in high-strength Mg-RE alloys is beneficial for the further design of Mg alloys with higher strength as well as excellent comprehensive performance.
基金support from Chinese Committee for Magnesium and its Application
文摘China has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （Mg） and its alloys in the world from a solid base laid by its prominent metallurgist and materials scientists over the past decades. Nowadays, a large number of young-generation researchers have been inspired by their predecessors and become the key participants in the fields of Mg alloys, which consequently led to the establishment of China Youth Scholar Society for Magnesium Alloys Research in 2015. Since then, the first two China Youth Scholars Symposiums on Mg Alloys Research had been held at Harbin （2015） and Chongqing （2016） China, respectively. A number of crucial research inter- ests related to fundamental and applied Mg research were discussed at the conferences and summarized in this short perspective, aiming to boost far-reaching initiatives for development of new Mg-based materials to satisfy the requirements for a broad range of industrial employments. Herein, four main aspects are included as follows： i） Plastic deformation mechanism and strengthening strategy, ii） Design and development of new Mg-based materials, iii） Key service properties, and iv） New processing technologies.
基金co-supported by the National Natural Science Foundation of China (Nos. 51571041, 51421001 and 51401190)
文摘Grain refinement could effectively enhance yield strength of Mg alloys according to the well-known Hall-Petch theory. For decades, many studies have been devoted to the factors influencing the Hall- Petch slope （k） in Mg alloys. Understanding the factors influencing k and their mechanisms could offer guidance to design and produce high-strength Mg alloys through effective grain refinement hardening. A review and comments of the past work on the factors influencing k in Mg alloys are presented. Results of these previous investigations demonstrate that the value of k in Mg alloys varies with texture, grain size, temperature and stain. The influence of texture and grain size on k is found to be an essential result of the variation of deformation mode on k value. Without the variation of deformation modes, it is revealed that texture could also impose a significant effect on k and this is also summarized and discussed in this paper. The reason for texture effect on k is analyzed based on the mechanism of Hall-Petch relationship. In addition, it is found in face-centered cubic （fcc） or body-centered cubic （bcc） metals that boundary parameters （boundary coherence, boundary energy and boundary diffusivity） could strengthen twinning or slips to a different extent. Therefore, the role of boundary parameters is also extended into the k values in Mg alloys and discussed in this paper. In the end, we discuss the future research perspective of Hall-Petch relationship in Mg alloys.
基金国家自然科学基金(批准号:2983719030230310+5 种基金20077004和20477004)北京市自然科学基金(批准号:89910028041003)资助项目教育部高等学校博士学科点专项科研基金(20010027017)中国科学院百人计划 大气边界层物理和大气化学国家重点实验室(LAPC)以及Swedish International Development Cooperation Agency(SIDA)部分资助项目
文摘以‘宁粳2号’为材料，采用田间小区试验方法研究了单季粳稻施用镁肥后对镁吸收分配的影响。结果表明，从拔节到始穗期，水稻体内镁的阶段吸收量和吸收速度最高，分别为7．22kg·hm^-2和0．40kg·hm^-2·d^-1；从拔节期到齐穗期，镁肥的施用促进了水稻对镁的吸收，其它生育期对外界镁浓度变化不敏感；镁肥的施用降低了镁在茎鞘和叶片中的分配比例，提高了镁在穗部的分配比例；齐穗后15～30d为穗部积累镁的高峰期；在本实验范围内，随施肥水平的提高，稻米中的镁含量升高，RVA（Rapid of viscosity analysis）谱中最终黏度、回复值及消减值显著下降，最高黏度、热浆黏度和崩解值显著上升，糊化温度没有明显差异。施用镁肥提高了稻米食味品质，这其中以120kg·hm^-2用量效果最好。
基金support from the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030006)National Natural Science Foundation of China(NSFC)(No.52071036)+1 种基金Key Research and Development Program of Zhejiang Province(No.2021C01086)the Fundamental Research Funds for the Central Universities Project(Nos.2021CDJCGJ009,SKLMT-ZZKT-2021M11)is also gratefully acknowledged.
文摘More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.
基金This work was supported by National Natural Sci-ence Foundation of China(51871069)Domain Foundation of Equipment Advance Research of 13th Five-year Plan(61409220118)Science and technology innovation ma-jor project of Ningbo City(2019B10103).
文摘Magnesium(Mg)alloys have received an increasing interest in the past two decades for their tremendous application potential.The strength and corrosion resistance levels of common Mg alloys are still relativity low,and especially they are to be improved simultaneously.The addition of rare earth(RE)to Mg alloys is believed to be beneficial for both the strength and corrosion resistance,and some RE-modified traditional Mg alloys have been studied and some new RE-containing Mg alloys have been developed by now.However,further simultaneous improvements in both strength and anti-corrosion require a better understanding of the behavior and mechanism of RE in Mg alloys.In this review,the common influence mechanisms of RE on mechanical and anti-corrosion properties of Mg alloys are summarized,and the latest research progress of RE-containing Mg alloys with simultaneously improved strength and corrosion resistance are introduced.It is demonstrated that the research on high-strength and high corrosion resistant RE-containing Mg alloys is still immature,and some opinions and suggestions are put forward for the synergetic improvement of the strength and corrosion resistance of Mg alloys,so as to contribute to the further development of Mg alloys with higher performance.
文摘This paper dealt with the effects of Pb 2+,Cd 2+ and their combined pollution on the contents of chlorophyll,potassium and calcium in Thuidium cymbifolium.The results showed that except at 0.1 mg Cd 2+·L -1,the chlorophyll content decreased with increasing Pb 2+ and Cd 2+ concentrations,which was 18% of the control at 100 mg Cd 2+·L -1,and decreased by 48.6% at 200 mg Pb 2+·L -1.The potassium and calcium contents also decreased with increasing pollutants concentrations,being decreased by 61.1% at 100 mg Cd 2+·L -1.Cd 2+ had a stronger toxicity than Pb 2+,and the toxicity of their combined pollution was stronger than that of each pollutant.Pb 2+ could increase the toxicity of Cd 2+.
