Eshkalak Kasra Einalipour, Sadeghzadeh Sadegh, Molaei Fatemeh
School of Advanced Technologies, Iran University of Science and Technology Tehran Iran
Mining and Geological Engineering Department, The University of Arizona Arizona USA.
RSC Adv. 2020 May 20;10(33):19134-19148. doi: 10.1039/d0ra03204b.
This study unveils CN, a new material that serves as an excellent reinforcement to enhance the mechanical properties of aluminum using a molecular dynamics simulation method. Results show that the CN nanosheets greatly improve the mechanical properties of aluminum-based nanocomposites. With only 1.3 wt% CN, the Young's modulus, fracture strength, and fracture strain increased by 27, 70, and 51 percent, respectively. A comparison between the reinforcement of graphene and CN in an aluminum (Al) matrix shows that in terms of the mechanical properties, the graphene-aluminum composite is weaker than the CN-aluminum composite in the tensile tests, but slightly stronger in the energy adsorption tests. Our findings show that the mechanical properties are highly dependent on the strain rate and temperature. The effects of various imperfections, such as the vacancy, crack, and void defects, on the mechanical properties were also studied. Results show that in the presence of void defects, the structure exhibited higher mechanical properties than when there were other defects. This phenomenon was found to be related to the decrease in the effective load transfer from aluminum to CN. Furthermore, by increasing the weight percent of the nanosheets up to 5%, the energy absorption rate increased by 25% compared to the pure aluminum. When CN was placed on top of the aluminum surface, the silicon nanoparticles were associated with a 35% energy adsorption by the nanocomposite. The results of this paper could be used to help understand and overcome some limitations in the fabrication of metallic nanocomposites with 2D material reinforcement.
本研究使用分子动力学模拟方法揭示了一种新型材料——碳氮化物（CN），它是一种优异的增强材料，可用于提高铝的力学性能。结果表明，CN纳米片极大地改善了铝基纳米复合材料的力学性能。仅添加1.3 wt%的CN，杨氏模量、断裂强度和断裂应变分别提高了27%、70%和51%。对石墨烯和CN在铝（Al）基体中的增强效果进行比较表明，在拉伸试验中，石墨烯-铝复合材料的力学性能比CN-铝复合材料弱，但在能量吸收试验中略强。我们的研究结果表明，力学性能高度依赖于应变率和温度。还研究了各种缺陷，如空位、裂纹和孔隙缺陷对力学性能的影响。结果表明，存在孔隙缺陷时，结构表现出比存在其他缺陷时更高的力学性能。发现这种现象与从铝到CN的有效载荷传递减少有关。此外，将纳米片的重量百分比增加到5%时，与纯铝相比，能量吸收率提高了25%。当CN置于铝表面上方时，硅纳米颗粒使纳米复合材料的能量吸收率提高了35%。本文的结果可用于帮助理解和克服二维材料增强金属纳米复合材料制备中的一些局限性。
