Sökning: "weld defects"

Visar resultat 1 - 5 av 34 avhandlingar innehållade orden weld defects.

1. 1. Weld Pool Simulations

   Författare :Marcus Edstorp; Högskolan Väst; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Arc Welding; Weld Pool; Multiphysics Simulations; Moving Boundaries; Free Surfaces; Mesh Motion; Two-Phase Flow; Incompressible Flow; Electromagnetics; Finite Element Methods; Applied mathematics; Tillämpad matematik; Manufacturing engineering; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik; Arc Welding; Weld Pool; Multiphysics Simulations; Moving Boundaries; Free Surfaces; Mesh Motion; Two-Phase Flow; Incompressible Flow; Electromagnetics; Finite Element Methods;

   Sammanfattning : This investigation is devoted to the study of welding and its effect on the workpiece, focusing on the thermo and fluid dynamical phenomena occuring during a autogenous or nonautogenous arc fusion welding process. Its aim is to simulate the behaviour of the weld pool and analyze the consequence of the solid-liquid phase change, thus obtaining a methodology for predicting the appearance of weld defects related to solidification and cooling. LÄS MER

3. 2. Computational weld mechanics : Towards simplified and cost effective FE simulations

   Författare :Ayjwat Awais Bhatti; Zuheir Barsoum; Lennart Josefson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Vehicle and Maritime Engineering; Farkostteknik;

   Sammanfattning : It is the demand of the world’s ever increasing energy crisis to reduce fuel consumption wherever possible. One way of meeting this demand is by reducing the weight of a structure by replacing thick plates of low strength steel with thin plates of high strength steel in the structure. LÄS MER

4. 3. Improved Quality Assurance of Fatigue Loaded Structures - The Necessary Shift from Technology Focus towards Information Driven Weld Evaluation

   Författare :Anna Öberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lean; fatigue; NDT; information; inspection; control; assurance; six sigma; quality; weld;

   Sammanfattning : The research has shown that the insufficient use of process information leads to unnecessary and costly safety margins in each step of production. This is, in short term, affecting the productivity of the company. Even more serious is the effect that insufficient use of process information has on product and process development in the long term. LÄS MER

5. 4. Residual Stress Analysis and Fatigue Assessment of Welded Steel Structures

   Författare :Zuheir Barsoum; Jack Samuelsson; Dan Zenkert; Stephen Maddox; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fatigue failure; welding; weld defects; welded joints; stress concentration; residual stress; linear elastic fracture mechanics; welding simulation; finite element analysis; fatigue crack growth.; Engineering mechanics; Teknisk mekanik;

   Sammanfattning : This doctoral thesis is concerned with fatigue life of welded structures. Several topics related to fatigue of welded structures are treated such as; weld defects and their influence on fatigue performance of welded structures, fatigue life prediction using LEFM (Linear Elastic Fracture Mechanics), fatigue testing, welding simulation, residual stress prediction and measurement and their influence on fatigue life. LÄS MER

7. 5. Microstructure and mechanical properties of Ti-6Al-4V welds produced with different processes

   Författare :Sakari Tolvanen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fatigue; welding; porosity; microstructure; defects; Ti-6Al-4V;

   Sammanfattning : Titanium alloys are widely used for components in the fan and compressor sections of aeroengines mainly because of their superior strength-to-weight ratio. Large static compressor components can be manufactured by welding together smaller subcomponents, which has potential to provide benefits such as higher buy-to-fly ratio and improved performance of the components. LÄS MER