欢迎您！东篱公司
退出
-
申报数据库
-
立项数据库
-
成果数据库
-
项目获奖数据库
中文摘要：
本文用分子动力学模拟研究了Ni熔体以不同冷速凝固后微观结构的演变规律，并通过理论计算确定出了Ni熔体凝固后获得理想非晶的临界条件．模拟结果发现冷速小于10^11K／s时，Ni熔体凝固后形成晶态组织；冷速在10^11K／s到10^14·5K／s之间时，Ni熔体凝固后形成由晶态结构与非晶态结构组成的混合组织．冷速小于10mK／s，Ni熔体凝固后形成的晶态组织具有fcc结构：冷速在10^10K／s到10^14.5K／s之间时，Ni熔体凝固后组织中的晶态由fcc和hcp结构层状镶嵌排列构成．通过分析模拟结果和计算结果，确定出了Ni熔体凝固后形成理想非晶的临界冷速为10^14．5K／s．并发现Ni熔体中临界晶核（冷速等于10^14．5K／s）和亚临界晶核（冷速大干10^14.5K／s）均由fcc和hcp组成层状偏聚结构，这表明Ni熔体中生长的晶体、临界晶核和晶胚的结构是相同的．
英文摘要：
The microstructures of nickel solidified at different cooling rates are studied by using molecular dynamics simulation and the critical condition for nickel melt to form ideal metallic glass is calculated. The simulation results show that the crystal structure is obtained after the nickel melt has been solidified at a cooling rate that is lower than 10^11 K/s; while a mixture is composed of crystal structure and amorphous structure when the cooling rate is in a region from 10^11 K/s to 10^14.5 K/s. The solidified crystal of nickel is of fcc structure when the cooling rate is lower than 10^10 K/s, while it changes into crystal structure composed of fcc and hcp when the cooling rate is between 10^10 K/s and 10^14.5 K/s. By analyzing the calculation and simulation results, it is determined that the critical cooling rate for nickel melt to form ideal metallic glass is 10^14.5 K/s. Moreover, it is found that the structures of the subcritical nuclei （the cooling rate is higher than 10^14.5 K/s）, critical nuclei （the cooling rate is 10^14.5 K/s）, and the growing crystal （the cooling rate is lower than 10^14.5 K/s） are the lamellar structures composed of fcc and hcp atoms, which indicates that the subcritical nuclei, critical nuclei and the growing crystal have the same structures.
同期刊论文项目
同项目期刊论文
Simulation of molecular dynamics of silver subcritical nuclei and crystal clusters during solidifica
Effects of T6 heat treatment on the microstructure, tensile properties, and fracture behavior of the
Non-isothermal crystallization kinetics and fragility of (Cu46Zr47Al7)(97)Ti-3 bulk metallic glass i
Molecular dynamics simulation of the atom cluster evolution in copper melt during solidification pro
The influence of Ni or Co substitution for Fe on glass forming ability and magnetic properties in th
期刊信息
位置：