欢迎访问《人工晶体学报》官方网站,今天是 分享到:

人工晶体学报 ›› 2017, Vol. 46 ›› Issue (12): 2514-2520.

• • 上一篇    下一篇

SiO2气凝胶纳米多孔结构的自组装过程模拟

张光磊;陈一泊;贾伟韬;赵朋媛;秦国强   

  1. 石家庄铁道大学材料科学与工程学院,石家庄,050043
  • 出版日期:2017-12-15 发布日期:2021-01-20

Self-assembly Simulation of Nano-porous Structure of Silica Aerogel

ZHANG Guang-lei;CHEN Yi-bo;JIA Wei-tao;ZHAO Peng-yuan;QIN Guo-qiang   

  • Online:2017-12-15 Published:2021-01-20

摘要: 基于分子动力学理论,模拟并计算了纳米多孔SiO2气凝胶的原子尺度模型和力学性能.SiO2气凝胶网络结构的自组装形成过程表明,当密度为0.078 g/cm3时,形成的结构以纳米团簇为主,难以形成连通的骨架结构;当密度为0.172 g/cm3及以上时,硅氧元素分布已扩展形成了连通的无定形骨架结构.通过对不同密度体系模型单轴施加应变并计算相应的应力值,得到应力-应变关系曲线,并依据弹性范围求得弹性模量.模拟结果表明,弹性模量与密度成一次线性关系,当气凝胶密度在0.078~0.443 g/cm3时,弹性模量为0.1265~0.7889 MPa.

关键词: 气凝胶;分子动力学;纳米多孔结构;自组装

Abstract: The atomic scale model and mechanical properties of SiO2 aerogels was simulated and calculated based on the principle of molecular dynamics .The results indicates that the structure is mainly nano-clusters and connected skeleton structure is difficult to form when the density is 0 .078 g/cm3 .The distribution of silica oxygen elements has been extended to a connected amorphous skeleton structure when the density is 0.172 g/cm3 and above.The stress-strain relationships curve were figured out by applying strains on the different density cell , and the elastic modulus was obtained in different elastic range.The simulation results shows that the elastic modulus is linear with the density .The elastic modulus changes from 0.1265 MPa to 0.7889 MPa when density ranges from 0.078 g/cm3 to 0.443 g/cm3 .

Key words: The atomic scale model and mechanical properties of SiO2 aerogels was simulated and calculated based on the principle of molecular dynamics .The results indicates that the structure is mainly nano-clusters and connected skeleton structure is difficult to form when the density is 0 .078 g/cm3 .The distribution of silica oxygen elements has been extended to a connected amorphous skeleton structure when the density is 0.172 g/cm3 and above.The stress-strain relationships curve were figured out by applying strains on the different density cell , and the elastic modulus was obtained in different elastic range.The simulation results shows that the elastic modulus is linear with the density .The elastic modulus changes from 0.1265 MPa to 0.7889 MPa when density ranges from 0.078 g/cm3 to 0.443 g/cm3 .

中图分类号: