应变率对氧化石墨烯水泥基复合材料微观力学性能的影响

Effect of Strain Rate on Micromechanical Properties of Graphene Oxide Cement-based Composites

研究不同氧化石墨烯掺量的水泥净浆在不同应变率作用下的硬度和弹性模量。结果表明:在氧化石墨烯掺量为0~0.06%的范围内,水泥净浆的弹性模量随氧化石墨烯掺量的增加而增大,掺量为0.06%时的弹性模量增强效果最佳,相比未掺时提高了39%,此时试件微观结构更加紧密,孔隙变小。应变率的改变对氧化石墨烯水泥净浆硬度的变化影响不大;在0.01s^-1~0.5s^-1应变率变化范围内,同一掺量氧化石墨烯水泥净浆的弹性模量随应变率的增加而增大,应变率为0.5s^-1时的弹性模量比应变率为0.01s^-1时提高了46%。

The study of hardness and elastic modulus of cement paste with different graphene oxide content under different strain rates were tested by nano indenter.The results showed that in the range of 0~0.06%of graphene oxide content,the elastic modulus of the cement paste increased with the increase of graphene oxide content.The elastic modulus of the cement paste was the best when the content was 0.06%,which increased by 39%compared with that without graphene oxide content.At this time,the microstructure of the sample was more compact and the pores were smaller.The change of strain rate has little effect on the change of hardness of graphene oxide cement paste.The elastic modulus of the same amount of graphene oxide cement paste varies with strain rate in the range of 0.01s^-1~0.5s^-1 strain rate.The increase in the modulus of elasticity at a strain rate of 0.5 s^-1 is 46%higher than that at a strain rate of 0.01 s^-1.