Search for dissertations about: "debond"

Showing result 11 - 15 of 18 swedish dissertations containing the word debond.

2. 11. Matrix and interface effects on microcracking in polymer composites

   Author : Anders Sjögren; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymera konstruktionsmaterial; Polymeric Composite Materials;

   Abstract : An underlying industrial problem for the present work is leakage of pressure vessels. Fluid leakage was confirmed to take place along a path of connected microcracks and delaminations. The thesis is concerned with the micromechanisms for microcracking studied by in-situ optical microscopy of cross-ply laminates. READ MORE

4. 12. Fatigue damage mechanisms in polymer matrix composites

   Author : Kristofer Gamstedt; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymera konstruktionsmaterial; Polymeric Composite Materials;

   Abstract : Polymer matrix composites are finding increased use in structural applications, in particular for aerospace and automotive purposes. Mechanical fatigue is the most common type of failure of structures in service. The relative importance of fatigue has yet to be reflected in design where static conditions still prevail. READ MORE

5. 13. Modelling of Delamination Growth in Composite Structures

   Author : Niklas E. Jansson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large deformation; interface; composite materials; 3D-shell; cohesive zone; regularization; shell element; delamination;

   Abstract : Delaminations constitute an important damage and failure mode in polymeric composite laminates. In order to explicitly incorporate and model the delamination progression within a finite element analysis, the meso-modelling concept is applied in the present work. The laminate is thereby represented by separate layers connected with interfaces. READ MORE

6. 14. Damage tolerance and residual strength of composite sandwich structures

   Author : Peter H. Bull; KTH; []
   Keywords : sandwich structure; damage tolerance; carbon fiber; compression after impact;

   Abstract : The exploitation of sandwich structures as a means toachieve high specific strength and stiffness is relatively new.Therefore, the knowledge of its damage tolerance is limitedcompared to other structural concepts such as truss bars andmonocoque plate solutions. Several aspects of the damage tolerance of sandwichstructures are investigated. READ MORE

7. 15. Micro-mechanical mechanisms for deformation in polymer-material structures

   Author : Jessica Strömbro; Peter Gudmundson; Per Gradin; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Length-scale effects; Strain gradient; Moisture change; Humidity change; Network model; Fibre model; Mathematical model; Polymer; Micro-indentation; Particle composite; Interfacial debonding; Matrix cracking; Paper; Mechano-sorptive creep; Accelerated creep; Other materials science; Övrig teknisk materialvetenskap;

   Abstract : In this thesis, the focus has been on micro-mechanical mechanisms in polymer-based materials and structures. The first part of the thesis treats length-scale effects on polymer materials. Experiments have showed that the smaller the specimen, the stronger is the material. READ MORE