• 文献标题:   Creep Behavior of Graphene Oxide, Silk Fibroin, and Cellulose Nanocrystal Bionanofilms
  • 文献类型:   Article
  • 作  者:   SHAKIL A, KIM S, POLYCARPOU AA
  • 作者关键词:   creep, finite element analysi, graphene nanoindentation, thin film
  • 出版物名称:   ADVANCED MATERIALS INTERFACES
  • ISSN:   2196-7350
  • 通讯作者地址:  
  • 被引频次:   3
  • DOI:   10.1002/admi.202101640 EA JAN 2022
  • 出版年:   2022

▎ 摘  要

Graphene oxide (GO), silk fibroin (SF), and cellulose nanocrystal (CNC) nanocomposite is a novel biomaterial with superior mechanical properties. Elevated temperature nanoindentation experiments using constant load hold method are performed to investigate temperature-dependent mechanical and creep behavior of the GO-SF-CNC nanocomposite. Hardness and reduced modulus of GO-SF-CNC are determined from experiments at 25, 40, 60, 80, and 100 degrees C, and yield strength and creep coefficients are predicted from finite element analysis using two-layer viscoplasticity theory. Results show that increasing the temperature from 25 to 80 degrees C, hardness, reduced modulus, and yield strength of GO-SF-CNC nanocomposite dramatically increase by 112%, 40%, and 140% respectively, and creep displacements during constant load hold reduce by 53%. It is attributed to increasing in crystallizations in the nanocomposite because of increasing in beta-sheet formations of SF material and reduction in water molecules in CNC material. However, at 100 degrees C, the mechanical properties deteriorate, and creep displacements increase because of water evaporation from the nanocomposite, making it weaker. Hardness-to-yield strength ratio is found within 1.84-2.06. Maximum creep exponent is 2.9 at 40 degrees C, which reduces to 2.06 at 80 degrees C and again increases to 2.27 at 100 degrees C.