Search for dissertations about: "built-in stress"

Showing result 1 - 5 of 16 swedish dissertations containing the words built-in stress.

2. 1. Integration of graphene into MEMS and NEMS for sensing applications

   Author : Xuge Fan; Frank Niklaus; Peter Steeneken; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Micro-electromechanical systems MEMS ; Nano-electromechanical systems NEMS ; heterogeneous 3D integration; Graphene; single-layer graphene; double-layer graphene; bilayer graphene; chemical vapor deposition CVD ; suspended graphene beams; suspended graphene membranes; doubly clamped; fully clamped; silicon on insulator SOI ; vapor hydrofluoric acid VHF ; Young’s modulus; built-in stress; built-in tension; piezoresistivity; gauge factor; accelerometer; resonators; electromechanical sensing; advanced transducers; humidity; gas sensing; sensitivity; CO2 sensing; graphene grain boundary; line defects; optical microscopy; wire bonding; Electrical Engineering; Elektro- och systemteknik;

   Abstract : This thesis presents a novel approach to integrate chemical vapor deposition (CVD) graphene into silicon micro- and nanoelectromechanical systems (MEMS/NEMS) to fabricate different graphene based MEMS/NEMS structures and explore mechanical properties of graphene as well as their applications such as acceleration sensing, humidity sensing and CO2 sensing. The thesis also presents a novel method of characterization of CVD graphene grain boundary based defects. READ MORE

4. 2. Residual Stress in Additive Manufacturing : Control using orientation and scan strategies

   Author : Prabhat Pant; Ru Peng; Johan Moverare; Kjell Simonsson; Thomas Niendorf; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Additive manufacturing; Residual stress; Neutron diffraction; FEM; Scan strategies; Build orientations;

   Abstract : Components with complex features that are designed with their function as a core aspect often are not viable to be manufactured with traditional methods. This has been a bottleneck in the past, leading to heavier parts with various sub-assemblies and a significant waste of material. READ MORE

5. 3. Residual Stress Distributions in Additively Manufactured Parts : Effect of Build Orientation

   Author : Prabhat Pant; Ru Lin Peng; Johan Moverare; Kjell Simonsson; Jonathan Almer; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Additive manufacturing; Residual stress; Neutron diffraction; FEM;

   Abstract : Additive manufacturing (AM) of parts using a layer by layer approach has seen a rapid increase in application for production of net shape or near-net shape complex parts, especially in the field of aerospace, automotive, etc. Due to the superiority of manufacturing complex shapes with ease in comparison to the conventional methods, interest in these kinds of processes has increased. READ MORE

6. 4. Controlling the Roll Responses of PCTC's

   Author : Carl-Johan Söder; Jakob Kuttenkeuler; Dominic Hudson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PCTC; parametric roll; roll response; roll damping; rudder control; roll mitigation; racking;

   Abstract : Modern Panamax Pure Car and Truck Carriers (PCTC) have become more vulnerable to critical roll responses as built in margins have been traded against increased transport efficiency. The research presented in this licentiate thesis aims at enhancing the predictability and control of these critical roll responses. READ MORE

7. 5. Design and Experiments with High Power Microwave Sources : The Virtual Cathode Oscillator

   Author : Cecilia Möller; Nils Brenning; Stefan Silfverskiöld; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High Power Microwaves Vircator;

   Abstract : High-Power Microwaves (HPM) can be used to intentionally disturb or destroy electronic equipment at a distance by inducing high voltages and currents.This thesis presents results from simulations and experiments with a narrow band HPM source, the vircator. READ MORE