As the lightest structural metal,Mg and Mg-based alloys have great potential applications in the aerospace,automotive and nuclear industries.However,such applications have been limited by low ductility and strength.Th...As the lightest structural metal,Mg and Mg-based alloys have great potential applications in the aerospace,automotive and nuclear industries.However,such applications have been limited by low ductility and strength.Theoretically,small grain sized structure can synchronously improve its ductility and strength.Yet,universally reliable grain ref inement techniques for the magnesium alloys are still under investigation and some are in strong debating.This paper presents a brief review of development of grain ref inement methods for magnesium alloys,which would contribute to a better understanding of the factors controlling grain ref inement and provide an outlook of future research in this fi eld.展开更多
A vital part of enhancing the ability of students to learn about advanced fabrication techniques is identifying the barriers to the student’s entry and excelling in the manufacturing field. In the Manufacturing and M...A vital part of enhancing the ability of students to learn about advanced fabrication techniques is identifying the barriers to the student’s entry and excelling in the manufacturing field. In the Manufacturing and Mechanical Technology fields, there exists an intimidating experience gap or barrier between professionals and novice students. The students’ participation in the design and fabrication of a fixture for manufacturing a mechanical part will aid in eliminating this barrier by making fuel cell’s bipolar plates production accessible to inexperienced technology students. The process of manufacturing a fixture for the production of hydrogen fuel cell and hydrogen purifier plates required a careful planning and step-by-step methodological implementation. Through the use of our designed fixture, it is now possible to teach students how to use a CNC milling machine with relative ease while also allowing for precision part machining. The setup of the fixture allows students to observe the necessary measures to properly machine a part while also teaching them the benefits of fixtures in the manufacturing industry. In summary, the purpose of this paper is to provide the students with applied learning experience through involving them in the design and fabrication of a multi-disciplinary mechanical fixture and the utilization of practice oriented teaching resources in a full scale learning environment.展开更多
基金supported by National Natural Science Foundation of China(No.50701030)China Postdoctoral Science Foundation(No.:20070410716)
文摘As the lightest structural metal,Mg and Mg-based alloys have great potential applications in the aerospace,automotive and nuclear industries.However,such applications have been limited by low ductility and strength.Theoretically,small grain sized structure can synchronously improve its ductility and strength.Yet,universally reliable grain ref inement techniques for the magnesium alloys are still under investigation and some are in strong debating.This paper presents a brief review of development of grain ref inement methods for magnesium alloys,which would contribute to a better understanding of the factors controlling grain ref inement and provide an outlook of future research in this fi eld.
文摘A vital part of enhancing the ability of students to learn about advanced fabrication techniques is identifying the barriers to the student’s entry and excelling in the manufacturing field. In the Manufacturing and Mechanical Technology fields, there exists an intimidating experience gap or barrier between professionals and novice students. The students’ participation in the design and fabrication of a fixture for manufacturing a mechanical part will aid in eliminating this barrier by making fuel cell’s bipolar plates production accessible to inexperienced technology students. The process of manufacturing a fixture for the production of hydrogen fuel cell and hydrogen purifier plates required a careful planning and step-by-step methodological implementation. Through the use of our designed fixture, it is now possible to teach students how to use a CNC milling machine with relative ease while also allowing for precision part machining. The setup of the fixture allows students to observe the necessary measures to properly machine a part while also teaching them the benefits of fixtures in the manufacturing industry. In summary, the purpose of this paper is to provide the students with applied learning experience through involving them in the design and fabrication of a multi-disciplinary mechanical fixture and the utilization of practice oriented teaching resources in a full scale learning environment.