Search for dissertations about: "improve hardness"

Showing result 1 - 5 of 58 swedish dissertations containing the words improve hardness.

  1. 1. Synthesis and Characterization of Transition Metal Diborides

    Author : Jimmy Thörnberg; Johanna Rosén; Per Persson; Helmut Riedl; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; DCMS; HiPIMS; Titanium Diboride; Titanium Aluminum Diboride; Chromium Diboride; Microstructure; Hardness; Oxidation Resistance;

    Abstract : This thesis is devoted towards physical vapor deposition (PVD) of thin films of transition-metal (TM) diborides, focused on the material system TiBx, Ti1-xAlxB2-y and CrBx. The metal diborides are a large family of compounds with both metallic and ceramic properties, due to its bonding nature being a mix of covalent and ionic bonds. READ MORE

  2. 2. Synthesis, Characterization, and Evaluation of Ag-based Electrical Contact Materials

    Author : Fang Mao; Ulf Jansson; Mikael Olsson; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electrical contact; bulk; coating; Ag-based alloys; Ag-based delafossite; AgI; graphene; graphene oxide; combinatorial material science; dc magnetron sputtering; friction; wear; hardness; contact resistance;

    Abstract : Ag is a widely used electrical contact material due to its excellent electrical properties. The problems with Ag are that it is soft and has poor tribological properties (high friction and wear in Ag/Ag sliding contacts). READ MORE

  3. 3. Label Cover Reductions for Unconditional Approximation Hardness of Constraint Satisfaction

    Author : Cenny Wenner; Johan Håstad; Irit Dinur; Numerical Analysis and Computer Science (NADA) Faculty of Science Stockholm University; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Optimization; NP; Approximation; Approximability; Inapproximability; Constraint Satisfaction; CSP; Boolean Analysis; Satisfiability; SAT; Acyclic Subgraph; Betweenness; Unique Games; Computer Science; Datalogi;

    Abstract : Problem solving is an integral aspect of modern society and includes such tasks as picking the fastest route to work, optimizing a production line, scheduling computer tasks, placing new bus stops, or picking a meal from available ingredients.We study the hardness of solving Constraint Satisfaction Problems (CSPs). READ MORE

  4. 4. Impact of Ionizing Radiation on 4H-SiC Devices

    Author : Muhammad Usman; Anders Hallén; Einar Örn Sveinbjörnsson; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon carbide; ionizing radiation; bipolar junction transistors; reliability; surface passivation; high-k dielectrics; MIS; radiation hardness;

    Abstract : Electronic components, based on current semiconductor technologies and operating in radiation rich environments, suffer degradation of their performance as a result of radiation exposure. Silicon carbide (SiC) provides an alternate solution as a radiation hard material, because of its wide bandgap and higher atomic displacement energies, for devices intended for radiation environment applications. READ MORE

  5. 5. Laser-arc treatment of aluminium alloys

    Author : Alexander Zolotarevski; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Manufacturing Systems Engineering; Produktionsutveckling;

    Abstract : The increasing use of aluminium alloys in high demand applications has lead to the development of a number of surface treatment technologies designed to improve hardness and wear characteristics. This thesis investigates the combination of a high power laser beam and an electric arc to produce new surfaces on aluminium alloys. READ MORE