東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Deformation and failure of glassy ma...

Rottler, Joerg Gerhard.

FindBook

Google Book

Amazon

博客來

Deformation and failure of glassy materials.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Deformation and failure of glassy materials./
作者:	Rottler, Joerg Gerhard.
面頁冊數:	112 p.
附註:	Source: Dissertation Abstracts International, Volume: 64-02, Section: B, page: 0776.
Contained By:	Dissertation Abstracts International64-02B.
標題:	Physics, Condensed Matter. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3080757

Deformation and failure of glassy materials.
Rottler, Joerg Gerhard.

Deformation and failure of glassy materials. - 112 p.

Source: Dissertation Abstracts International, Volume: 64-02, Section: B, page: 0776.

Thesis (Ph.D.)--The Johns Hopkins University, 2003.

Elastoplastic deformation of disordered solids and the formation of polymer crazes in amorphous polymer glasses are studied using large-scale molecular dynamics simulations. It is shown that the pressure-modified von Mises criterion accurately describes the maximum shear yield stress under general loading conditions. The pressure coefficient is insensitive to most model parameters, but is related to the bead geometry in analogy to friction coefficients. The yield stress decreases linearly with rising temperature and the strain rate dependence can be described by a power-law, or in a limited range, by a logarithm. The rate dependence does not vary with temperature, which is inconsistent with simple rate-state models of thermal activation such as the Eyring model. An analysis of the dynamics of the local stress distribution as well as modern phenomenological theories of rheology of glassy materials are discussed in light of these findings.Subjects--Topical Terms:

1018743
Physics, Condensed Matter.

Deformation and failure of glassy materials.
LDR:03198nmm 2200301 4500 001 1858944
005 20041020095006.5
008 130614s2003 eng d
035 $a (UnM)AAI3080757
035 $a AAI3080757
040 $a UnM $c UnM
100 1 $a Rottler, Joerg Gerhard. $3 1946612
245 1 0 $a Deformation and failure of glassy materials.
300 $a 112 p.
500 $a Source: Dissertation Abstracts International, Volume: 64-02, Section: B, page: 0776.
500 $a Adviser: Mark O. Robbins.
502 $a Thesis (Ph.D.)--The Johns Hopkins University, 2003.
520 $a Elastoplastic deformation of disordered solids and the formation of polymer crazes in amorphous polymer glasses are studied using large-scale molecular dynamics simulations. It is shown that the pressure-modified von Mises criterion accurately describes the maximum shear yield stress under general loading conditions. The pressure coefficient is insensitive to most model parameters, but is related to the bead geometry in analogy to friction coefficients. The yield stress decreases linearly with rising temperature and the strain rate dependence can be described by a power-law, or in a limited range, by a logarithm. The rate dependence does not vary with temperature, which is inconsistent with simple rate-state models of thermal activation such as the Eyring model. An analysis of the dynamics of the local stress distribution as well as modern phenomenological theories of rheology of glassy materials are discussed in light of these findings.
520 $a We then present a comprehensive investigation of the deformation of glassy polymeric systems into a dense load-bearing network of fibrils and voids called a craze at large strains. This expansion takes place in the form of a drawing process, where the strain rate is strongly localized in a narrow interface region between dense polymer and craze. The expansion is controlled by some polymer chain segments between entanglements that are stretched taut during crazing. We also find that the distribution of tension in the craze develops an exponential force tail in close analogy to compressed jammed systems such as granular media. This highly anisotropic stress distribution and the localization of large forces on relatively few chains indicate that earlier models of the crazing process that treat the polymer as a viscous fluid with hydrodynamic interactions are incorrect. Simulations and simple scaling arguments are presented that describe craze breakdown through disentanglement or chain scission.
520 $a Glassy polymers exhibit an unusually high fracture energy, which is 3–4 orders of magnitude larger than the interfacial free energy change. We conclude by calculating this enhancement in a multiscale approach that combines molecular level results of craze failure with an analytic argument for the onset of crack propagation on the continuum scale.
590 $a School code: 0098.
650 4 $a Physics, Condensed Matter. $3 1018743
650 4 $a Chemistry, Polymer. $3 1018428
650 4 $a Engineering, Mechanical. $3 783786
690 $a 0611
690 $a 0495
690 $a 0548
710 2 0 $a The Johns Hopkins University. $3 1017431
773 0 $t Dissertation Abstracts International $g 64-02B.
790 1 0 $a Robbins, Mark O., $e advisor
790 $a 0098
791 $a Ph.D.
792 $a 2003
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3080757