Search for dissertations about: "Ni Hard"

Showing result 1 - 5 of 27 swedish dissertations containing the words Ni Hard.

2. 1. Cutting Edge Titanium-based CVD Hard Coatings

   Author : Linus von Fieandt; Mats Boman; Ulf Jansson; Erik Lindahl; Tommy Larsson; Henrik Pedersen; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; CVD; Hard coatings; Ti C; N ; TiN;

   Abstract : Modern tools for metal cutting applications, such as turning or milling, are typically improved with a thin protective coating. Despite being only a few microns thick, the coating can increase the lifetime of the tool by more than 100 times compared to an uncoated tool. Two different types of techniques are normally used to deposit the coatings, i. READ MORE

4. 2. Internal Tar/CH4 Reforming in Biomass Dual Fluidised Bed Gasifiers towards Fuel Synthesis

   Author : Kristina Göransson; Per Engstrand; Wennan Zhang; Kevin J Whitty; Mittuniversitetet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Allothermal gasification; Bio-automotive fuels; Biomass gasification; Catalytic bed-material; Dual fluidised bed; Ni-catalyst; Syngas cleaning; Tar removal; Tar CH4 reforming;

   Abstract : Production of high-quality syngas from biomass gasification in a dual fluidised bed gasifier (DFBG) has made a significant progress in R&D and Technology demonstration. An S&M scale bio-automotive fuel plant close to the feedstock resources is preferable as biomass feedstock is widely sparse and has relatively low density, low heating value and high moisture content. READ MORE

5. 3. Defects in Austenitic Steels and Hard Metals - A DFT-based Study

   Author : Ruiwen Xie; Levente Vitos; Ilja Turek; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; defects; austenitic steels; cemented carbides; ab-initio; Teknisk materialvetenskap; Materials Science and Engineering;

   Abstract : Materials are never 100% pure due to the limitation of purification method or manufacturing process. Nor are they perfect, especially under deformation. The present work aims to explore different roles played by the defects in austenitic steels and hard metals. READ MORE

6. 4. Ab initio and phenomenological modeling of materials related to CVD hard coatings

   Author : Axel Forslund; Andrei V. Ruban; Paul Erhart; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk materialvetenskap; Materials Science and Engineering;

   Abstract : This thesis describes the work based on two different tools in computational materials science: a first-principles approach, namely that of density functional theory, and the CALPHAD approach.These two methods were used in this work to calculate properties of materials related to hard coatings, in particular coatings produced with chemical vapor deposition for the purpose of wear protection in cutting tools. READ MORE

7. 5. Microstructure of a cubic boron nitride tool material before and after hard turning

   Author : Jenny Angseryd; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EELS; cBN; microstructure; PCBN; adherent layer; EDX; wear; SEM; EFTEM; TEM;

   Abstract : AbstractPolycrystalline cubic boron nitride (PCBN) materials are widely used in turning of hardened steels due to their beneficial mechanical properties like high hardness at elevated temperatures and, compared to diamond, for being more chemically stable towards iron at temperatures typical for turning operations (800-1000˚C). The wear of PCBN tools is influenced by several factors, like machining parameters, different tool geometries and varying composition of PCBN tools as well as workpiece material. READ MORE