ATOMISTIC MODELING OF PLASTIC-DEFORMATION OF GLASSY-POLYMERS

被引:131
作者
MOTT, PH
ARGON, AS
SUTER, UW
机构
[1] MIT,DEPT MAT SCI & ENGN,CAMBRIDGE,MA 02139
[2] MIT,DEPT MECH ENGN,CAMBRIDGE,MA 02139
[3] MIT,DEPT CHEM ENGN,CAMBRIDGE,MA 02139
[4] SWISS FED INST TECHNOL,INST POLYMERE,CH-8092 ZURICH,SWITZERLAND
来源
PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES | 1993年 / 67卷 / 04期
基金
美国国家科学基金会;
关键词
D O I
10.1080/01418619308213969
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
A detailed atomistic approach has been used to investigate the kinematics of plastic deformation in glassy atactic polypropylene to 20% strain. The microstructural stress-strain behaviour was found to consist of smooth reversible portions bounded by irreversible sharp stress drops indicating plastic rearrangement of the structure. Averaging the stress-strain behaviour over an ensemble of 1.815 nm microstructures showed a yield point in the neighbourhood of 5-7% strain. The transformation shear strain for plastic structural rearrangements was found to be broadly distributed, averaging 1.5% shear strain with a standard deviation of 2.6% shear strain. Combining this result with the activation volume measurements of common glassy polymers showed the size of the plastically transforming region to have a diameter of about 10 nm, thus involving several thousand segments. The transformation shear strain was independent of the system size. Scrutiny of the molecular segment motions associated with plastic rearrangements showed no recurring simple kinematical configurations and no correlation of the local atomic strain to topological features of the chain.
引用
收藏
页码:931 / 978
页数:48
相关论文
共 45 条
[21]  
HILLSTROM K, 1976, ANL297 APPL MATH DIV
[22]  
HUTNIK M, 1993, IN PRESS MACROMOLECU
[23]  
KHALATUR PG, 1983, VYSOKOMOL SOEDIN A+, V25, P1517
[24]   MOLECULAR-DYNAMICS SIMULATION OF VITRIFICATION AND PLASTIC-DEFORMATION OF A 2-DIMENSIONAL LENNARD-JONES MIXTURE [J].
KOTELYANSKII, MJ ;
MAZO, MA ;
OLEYNIK, EF ;
GRIVTSOV, AG .
PHYSICA STATUS SOLIDI B-BASIC RESEARCH, 1991, 166 (01) :25-42
[25]  
LEE WA, 1975, POLYM HDB, P137
[26]  
Li J.C.M, 1978, METALLIC GLASSES, P224
[27]   THE ATOMIC STRAIN TENSOR [J].
MOTT, PH ;
ARGON, AS ;
SUTER, UW .
JOURNAL OF COMPUTATIONAL PHYSICS, 1992, 101 (01) :140-150
[28]  
MOTT PH, 1993, UNPUB PHIL MAG
[29]  
OLEYNIK EF, 1990, HIGH PERFORM POLYM, P79
[30]   DEFECT DIFFUSION-MODEL FOR VOLUME AND ENTHALPY RECOVERY IN AMORPHOUS POLYMERS [J].
PEREZ, J .
POLYMER, 1988, 29 (03) :483-489