During the China's Tiangong-2(TG-2) flight mission, the experiments of 18 kinds of material samples were conducted in space by using a Multiple Materials Processing Furnace(MMPF) mounted in the orbital module of t...During the China's Tiangong-2(TG-2) flight mission, the experiments of 18 kinds of material samples were conducted in space by using a Multiple Materials Processing Furnace(MMPF) mounted in the orbital module of the TG-2 space laboratory. After the experiments of 12 kinds of samples of the first and second batches were completed successfully, astronauts packed and brought them back to the ground by ShenzhouII spacecraft. By studying processing and formation on semiconductor and optoelectronics materials, metal alloys and metastable materials, functional single-crystal, micro-and nano-composite materials encapsulated in sample ampoules both in space and on Earth, we expect to explore some physical and chemical processes and mechanism of the materials formation that are normally obscured and therefore are difficult to study quantitatively on the ground due to the gravity-induced convection, to obtain the processing and synthesis technology for preparing high quality materials, and lead to the improvement and development of materials processing techniques on Earth, and also develop the experiment device and comprehensive ability for materials experiment in microgravity environment. This report briefly introduces the main points of each research work and preliminary comparative analysis results of 12 samples carried out by scientists undertaking research task.展开更多
Orbital experimental researches on crystal growth of Mn-doped GaSb and Bi2Se0.21Te2.79 are briefly summarized.The space experiments were completed in September of 2007 on broad the Foton-M3 satellite of Russia.Ground-...Orbital experimental researches on crystal growth of Mn-doped GaSb and Bi2Se0.21Te2.79 are briefly summarized.The space experiments were completed in September of 2007 on broad the Foton-M3 satellite of Russia.Ground-based researches on the solidification behaviors of Al-Al3Ni,AlAl2Cu,Ag-Cu eutectic,Al-Pb monotectic and Cu-Co peritectic alloys in a 50-meter-high drop tube were investigated.New experimental results on the ultrasonic field and the temperature recycling induced to chiral symmetry breaking of NaClO3 crystal also were reported in the present paper.展开更多
Firstly,recent research works of high undercooling and rapid solidification of metallic alloys under ground simulation conditions in Northwestern Polytechnical University are reviewed.Secondly,under normal gravity and...Firstly,recent research works of high undercooling and rapid solidification of metallic alloys under ground simulation conditions in Northwestern Polytechnical University are reviewed.Secondly,under normal gravity and microgravity of binary to quinary Nickel-base single crystal alloys with different contents of W,Ta,Al and Ti elements are comparatively investigated by Institute of Metal Research using drop tube.Thirdly,solidification and crystal growth of SJ10-Recoverable Scientific Experiment Satellite by Institute of Semiconductors is introduced.展开更多
Microgravity science is an important branch of space science.Its major objective is to study the laws of materials movement in microgravity,as well as to reveal the influence of gravity on the movement of materials in...Microgravity science is an important branch of space science.Its major objective is to study the laws of materials movement in microgravity,as well as to reveal the influence of gravity on the movement of materials in different gravity environments.Application researches relevant to these basic studies are also important contents of microgravity science.The advanced subjects,to some extent,reflect the ability of human beings to understand nature and the R&D level in this field in various countries.In this paper,the recent progress and the latest achievements of microgravity science and application researches in China aboard space platforms such as the Core Capsule Tianhe of the China Space Station(CSS)and satellites,as well as utilizing ground-based short-term microgravity facilities such as the Drop Tower Beijing and TUFF,are summarized,which cover the following sub-disciplines:microgravity fluid physics,microgravity combustion science,space materials science,space fundamental physics,space bio-technology,and relevant space technology applications.展开更多
During 2012–2014, the main research activities from microgravity material research were focused on, which include study of microgravity effects on collagen fibrillogenesis and HAP crystallization, microgravity experi...During 2012–2014, the main research activities from microgravity material research were focused on, which include study of microgravity effects on collagen fibrillogenesis and HAP crystallization, microgravity experiments using drop tube, and research of thermoelectric materials for space.This paper summarizes all these activities.展开更多
The virtual absence of gravity-dependent phenomena in microgravity allows an in-depth understanding of fundamental events that are normally obscured and therefore are difficult to study quantitatively on Earth.Of part...The virtual absence of gravity-dependent phenomena in microgravity allows an in-depth understanding of fundamental events that are normally obscured and therefore are difficult to study quantitatively on Earth.Of particular interest is that the low-gravity environment aboard space provides a unique platform to synthesize alloys of semiconductors with homogeneous composition distributions,on both the macroscopic and microscopic scales,due to the much reduced buoyancy-driven convection.On the other hand,the easy realization of detached solidification in microgravity suppresses the formation of defects such as dislocations and twins,and thereby the crystallographic perfection is greatly increased.Moreover,the microgravity condition offers the possibilities to elucidate the liquid/solid interfacial structures,as well as clarify the microstructure evolution path of the metal alloys(or composites)during the solidification process.Motivated by these facts,growths of compound semiconductors and metal alloys were carried out under microgravity by using the drop tube,or on the scientific platforms of Tiangong-2 and SJ-10.The following illustrates the main results.展开更多
使用高度为50 m的落管研究了Sn-20%(质量分数) Ni包晶合金在重力和微重力作用下的凝固行为。用金相显微镜(OM)观察了合金的凝固组织并使用图像处理软件IPP(Image Pro Plus)统计了样品中的初生相、包晶相以及终凝相的含量,使用能谱仪(EDS...使用高度为50 m的落管研究了Sn-20%(质量分数) Ni包晶合金在重力和微重力作用下的凝固行为。用金相显微镜(OM)观察了合金的凝固组织并使用图像处理软件IPP(Image Pro Plus)统计了样品中的初生相、包晶相以及终凝相的含量,使用能谱仪(EDS)和X射线衍射(XRD)仪分析了样品凝固组织中的成分分布和组成相。结果表明,Sn-20%Ni包晶合金的凝固以初生相在固液界面前沿形核、枝晶生长和包晶反应的形式进行,重力对初生相的生成和包晶反应都有显著的影响,在微重力作用下的微观组织配比、分布以及合金元素的分布都与在重力作用下明显不同。在重力的作用下残余初生相的含量和残余初生相和包晶相的总量总是比在重力作用下的低,而包晶相的含量则总是比在微重力作用下的高。同时,样品中溶质元素的分布与残余初生相和包晶相的总量的分布趋势基本一致。结果表明,微重力环境有利于Sn-20%Ni合金初生相的形核和长大,而重力环境则促进包晶反应,其原因与重力导致的浮力对流和晶核沉积有关。展开更多
The solidification microstructure of Al-Ni, Al-Cu, Ag-Cu, Al-Pb and Cu-Co alloys quenched in silicone oil before and after free fall in evacuated 50 m drop tube were investigated contrastively. The effect of micrograv...The solidification microstructure of Al-Ni, Al-Cu, Ag-Cu, Al-Pb and Cu-Co alloys quenched in silicone oil before and after free fall in evacuated 50 m drop tube were investigated contrastively. The effect of microgravity on the solidification process of medium-low-melting-point eutectic, monotectic and peritectic alloys were ana-lyzed and discussed. The results indicated that the effects of microgravity on the eutectic cell shape, the pattern in eutectic cell and the inter-eutectic spacing were different for different types of eutectic systems; the size distribution of Pb particles in Al-5wt% Pb monotectic alloy was significantly changed by microgravity; and the shape of retained primary α-Co phase in Cu-10wt%Co peritectic alloy was also changed by microgravity. These results are beneficial for people to further identify and analyze the solidification behavior of multiphase alloys under microgravity.展开更多
文摘During the China's Tiangong-2(TG-2) flight mission, the experiments of 18 kinds of material samples were conducted in space by using a Multiple Materials Processing Furnace(MMPF) mounted in the orbital module of the TG-2 space laboratory. After the experiments of 12 kinds of samples of the first and second batches were completed successfully, astronauts packed and brought them back to the ground by ShenzhouII spacecraft. By studying processing and formation on semiconductor and optoelectronics materials, metal alloys and metastable materials, functional single-crystal, micro-and nano-composite materials encapsulated in sample ampoules both in space and on Earth, we expect to explore some physical and chemical processes and mechanism of the materials formation that are normally obscured and therefore are difficult to study quantitatively on the ground due to the gravity-induced convection, to obtain the processing and synthesis technology for preparing high quality materials, and lead to the improvement and development of materials processing techniques on Earth, and also develop the experiment device and comprehensive ability for materials experiment in microgravity environment. This report briefly introduces the main points of each research work and preliminary comparative analysis results of 12 samples carried out by scientists undertaking research task.
基金Supported by the Chinese Manned Spaceflight Programs and Chinese Space Agency
文摘Orbital experimental researches on crystal growth of Mn-doped GaSb and Bi2Se0.21Te2.79 are briefly summarized.The space experiments were completed in September of 2007 on broad the Foton-M3 satellite of Russia.Ground-based researches on the solidification behaviors of Al-Al3Ni,AlAl2Cu,Ag-Cu eutectic,Al-Pb monotectic and Cu-Co peritectic alloys in a 50-meter-high drop tube were investigated.New experimental results on the ultrasonic field and the temperature recycling induced to chiral symmetry breaking of NaClO3 crystal also were reported in the present paper.
文摘Firstly,recent research works of high undercooling and rapid solidification of metallic alloys under ground simulation conditions in Northwestern Polytechnical University are reviewed.Secondly,under normal gravity and microgravity of binary to quinary Nickel-base single crystal alloys with different contents of W,Ta,Al and Ti elements are comparatively investigated by Institute of Metal Research using drop tube.Thirdly,solidification and crystal growth of SJ10-Recoverable Scientific Experiment Satellite by Institute of Semiconductors is introduced.
文摘Microgravity science is an important branch of space science.Its major objective is to study the laws of materials movement in microgravity,as well as to reveal the influence of gravity on the movement of materials in different gravity environments.Application researches relevant to these basic studies are also important contents of microgravity science.The advanced subjects,to some extent,reflect the ability of human beings to understand nature and the R&D level in this field in various countries.In this paper,the recent progress and the latest achievements of microgravity science and application researches in China aboard space platforms such as the Core Capsule Tianhe of the China Space Station(CSS)and satellites,as well as utilizing ground-based short-term microgravity facilities such as the Drop Tower Beijing and TUFF,are summarized,which cover the following sub-disciplines:microgravity fluid physics,microgravity combustion science,space materials science,space fundamental physics,space bio-technology,and relevant space technology applications.
文摘During 2012–2014, the main research activities from microgravity material research were focused on, which include study of microgravity effects on collagen fibrillogenesis and HAP crystallization, microgravity experiments using drop tube, and research of thermoelectric materials for space.This paper summarizes all these activities.
基金Supports by the National Natural Science Foundation of China(U1738114)the Strategic Priority Research Program on Space Science,the Chinese Academy of Sciences(XDA15051200)+1 种基金the China's Manned Space Station Project(TGJZ800-2-RW024)the Chinese manned space flight pre-research project(030302)
文摘The virtual absence of gravity-dependent phenomena in microgravity allows an in-depth understanding of fundamental events that are normally obscured and therefore are difficult to study quantitatively on Earth.Of particular interest is that the low-gravity environment aboard space provides a unique platform to synthesize alloys of semiconductors with homogeneous composition distributions,on both the macroscopic and microscopic scales,due to the much reduced buoyancy-driven convection.On the other hand,the easy realization of detached solidification in microgravity suppresses the formation of defects such as dislocations and twins,and thereby the crystallographic perfection is greatly increased.Moreover,the microgravity condition offers the possibilities to elucidate the liquid/solid interfacial structures,as well as clarify the microstructure evolution path of the metal alloys(or composites)during the solidification process.Motivated by these facts,growths of compound semiconductors and metal alloys were carried out under microgravity by using the drop tube,or on the scientific platforms of Tiangong-2 and SJ-10.The following illustrates the main results.
文摘使用高度为50 m的落管研究了Sn-20%(质量分数) Ni包晶合金在重力和微重力作用下的凝固行为。用金相显微镜(OM)观察了合金的凝固组织并使用图像处理软件IPP(Image Pro Plus)统计了样品中的初生相、包晶相以及终凝相的含量,使用能谱仪(EDS)和X射线衍射(XRD)仪分析了样品凝固组织中的成分分布和组成相。结果表明,Sn-20%Ni包晶合金的凝固以初生相在固液界面前沿形核、枝晶生长和包晶反应的形式进行,重力对初生相的生成和包晶反应都有显著的影响,在微重力作用下的微观组织配比、分布以及合金元素的分布都与在重力作用下明显不同。在重力的作用下残余初生相的含量和残余初生相和包晶相的总量总是比在重力作用下的低,而包晶相的含量则总是比在微重力作用下的高。同时,样品中溶质元素的分布与残余初生相和包晶相的总量的分布趋势基本一致。结果表明,微重力环境有利于Sn-20%Ni合金初生相的形核和长大,而重力环境则促进包晶反应,其原因与重力导致的浮力对流和晶核沉积有关。
文摘The solidification microstructure of Al-Ni, Al-Cu, Ag-Cu, Al-Pb and Cu-Co alloys quenched in silicone oil before and after free fall in evacuated 50 m drop tube were investigated contrastively. The effect of microgravity on the solidification process of medium-low-melting-point eutectic, monotectic and peritectic alloys were ana-lyzed and discussed. The results indicated that the effects of microgravity on the eutectic cell shape, the pattern in eutectic cell and the inter-eutectic spacing were different for different types of eutectic systems; the size distribution of Pb particles in Al-5wt% Pb monotectic alloy was significantly changed by microgravity; and the shape of retained primary α-Co phase in Cu-10wt%Co peritectic alloy was also changed by microgravity. These results are beneficial for people to further identify and analyze the solidification behavior of multiphase alloys under microgravity.