化学物理学报
化學物理學報
화학물이학보
CHINESE JOURNAL OF CHEMICAL PHYSICS
2006年
4期
294-300
,共7页
倪向贵%王宇%张重%王秀喜
倪嚮貴%王宇%張重%王秀喜
예향귀%왕우%장중%왕수희
单壁碳纳米管%螺旋相关%尺寸相关%应变相关%泊松比
單壁碳納米管%螺鏇相關%呎吋相關%應變相關%泊鬆比
단벽탄납미관%라선상관%척촌상관%응변상관%박송비
Single-walled carbon nanotube%Chiral dependence%Size dependence%Strain dependence%Poisson's ratio
使用分子动力学方法模拟了单壁碳纳米管的拉伸变形行为和泊松比,并从单壁碳纳米管晶胞单元的结构特征角度,系统分析了管径、螺旋性和应变对力学性能的影响.模拟结果显示,单臂性碳纳米管(8,8)-(22,22)和锯齿性碳纳米管(9,0)-(29,0)的拉伸弹性变形可以分别达到35%-38%和20%-27%,拉伸条件下这些碳纳米管的弹性模量随管径的增大从960 GPa下降到750 GPa,并且锯齿性碳纳米管的弹性模量比单臂性碳纳米管的弹性模量要高.通过对三根具有相同直径和不同螺旋性的碳纳米管(9,9),(12,6)和(16,0)分别在拉伸和压缩条件下的模拟发现,随着变形的增大,碳纳米管的泊松比将减小;在相同的拉伸应变下,碳纳米管的泊松比随其螺旋角的减小而减小,而在相同的压缩应变下,碳纳米管的泊松比随其螺旋角的减小而增大.
使用分子動力學方法模擬瞭單壁碳納米管的拉伸變形行為和泊鬆比,併從單壁碳納米管晶胞單元的結構特徵角度,繫統分析瞭管徑、螺鏇性和應變對力學性能的影響.模擬結果顯示,單臂性碳納米管(8,8)-(22,22)和鋸齒性碳納米管(9,0)-(29,0)的拉伸彈性變形可以分彆達到35%-38%和20%-27%,拉伸條件下這些碳納米管的彈性模量隨管徑的增大從960 GPa下降到750 GPa,併且鋸齒性碳納米管的彈性模量比單臂性碳納米管的彈性模量要高.通過對三根具有相同直徑和不同螺鏇性的碳納米管(9,9),(12,6)和(16,0)分彆在拉伸和壓縮條件下的模擬髮現,隨著變形的增大,碳納米管的泊鬆比將減小;在相同的拉伸應變下,碳納米管的泊鬆比隨其螺鏇角的減小而減小,而在相同的壓縮應變下,碳納米管的泊鬆比隨其螺鏇角的減小而增大.
사용분자동역학방법모의료단벽탄납미관적랍신변형행위화박송비,병종단벽탄납미관정포단원적결구특정각도,계통분석료관경、라선성화응변대역학성능적영향.모의결과현시,단비성탄납미관(8,8)-(22,22)화거치성탄납미관(9,0)-(29,0)적랍신탄성변형가이분별체도35%-38%화20%-27%,랍신조건하저사탄납미관적탄성모량수관경적증대종960 GPa하강도750 GPa,병차거치성탄납미관적탄성모량비단비성탄납미관적탄성모량요고.통과대삼근구유상동직경화불동라선성적탄납미관(9,9),(12,6)화(16,0)분별재랍신화압축조건하적모의발현,수착변형적증대,탄납미관적박송비장감소;재상동적랍신응변하,탄납미관적박송비수기라선각적감소이감소,이재상동적압축응변하,탄납미관적박송비수기라선각적감소이증대.
Tensile deformation behaviors and the Poisson's ratio of single-walled carbon nanotubes (SWCNTs) are numerically studied, using the molecular dynamics (MD) method. Effects of several structural features of crystal cells of SWCNTs, i.e., the size, chirality and strain, on their mechanical properties are analyzed systematically. The simulations indicate that Armchair SWCNTs (8, 8)-(22, 22) and Zigzag SWCNTs (9,0)-(29,0) can be stretched by 35%-38% and 20%-27% without sign of plasticity, respectively. The Young's modulus of SWCNTs under tension ranges from 960 GPa to 750 GPa as their radii increase. The Young's modulus of zigzag SWCNTs is higher than that of armchair SWCNTs. Additionally, three SWCNTs (9,9),(12,6) and (16,0) are investigated to obtain their Poisson's ratio under tensile and compressive loading. The results show that the Poisson's ratio of nanotubes decreases generally as the strain increases. Under the same tensile strain, the Poisson's ratio decreases as the chiral angles of SWCNTs decrease, while their Poisson's ratios increase under the same compressive strain.