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Visar resultat 1 - 5 av 9 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Topology optimization of non-linear, dissipative structures and materials

   Författare :Niklas Ivarsson; Hållfasthetslära; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Topology optimization; Stiffness optimization; Finite strain; Rate-dependent plasticity; Discrete adjoint sensitivity analysis;

   Sammanfattning : Topology optimization is a mathematical tool for finding optimal distributions of material phases within a design domain. It is commonly used in early design stages to generate conceptual structural layouts. Ultimately, designs generated by topology optimization consist of distinct material phases with enhanced performance. LÄS MER

3. 2. Modeling of Inelastic Response of Metals with Emphasis on Cyclic Viscoplasticity

   Författare :Magnus Ekh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large strains; integration; anisotropy; plasticity; creep; viscoplasticity; kinematic hardening; metals; damage; calibration;

   Sammanfattning : This thesis is concerned with the continuum modeling of the macroscopic behavior of engineering metals, in particular as part of life prediction strategies. Focus is primarily placed on the formulation and numerics of models for cyclic rate-dependent response. LÄS MER

4. 3. A Damage-Based Interface Model: Application to the Degradation and Failure of a Polycrystalline Microstructure

   Författare :Patrik Cannmo; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; damage; polycrystalline microstructure; degradation; slip and dilatation; interfaces; FE-calculations; viscoplasticity; plasticity; failure;

   Sammanfattning : A constitutive model for material interfaces is presented. The model is based on damage coupled to plastic (or viscoplastic) slip and dilatation, and it is able to describe the successive degradation and failure of an interface. LÄS MER

5. 4. Development of Energy-based Damage and Plasticity Models for Asphalt Concrete Mixtures

   Författare :Ibrahim Onifade; Björn Birgisson; Linbing Wang; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; energy-based models; damage; X-ray computed tomography; continuum plasticity mechanics CPM; effective micro-crack stress; Transportvetenskap; Transport Science;

   Sammanfattning : Characterizing the full range of damage and plastic behaviour of asphalt mixtures under varying strain-rates and stress states is a complex and challenging task. One reason for this  is partly due to the strain rate and temperature dependent nature of the material as well as the variation in the properties of the constituent materials that make up the composite asphalt mixture. LÄS MER

7. 5. Modelling of high strain rate plasticity and metal cutting

   Författare :Dan Wedberg; Jesper Hattel; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material Mechanics; Materialmekanik;

   Sammanfattning : Metal cutting is one of the most frequently used forming processes in the manufacturing industry. Extensive effort is made to improve its process and simulation has become an integrated part, not only in the product development process but also in the customer relations. LÄS MER