Sökning: "powder surface"

Visar resultat 11 - 15 av 274 avhandlingar innehållade orden powder surface.

  1. 11. Metal Particles – Hazard or Risk? Elaboration and Implementation of a Research Strategy from a Surface and Corrosion Perspective

    Författare :Klara Midander; Inger Odnevall Wallinder; Sannakaisa Virtanen; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; ferro-chromium alloy; metal particles; bioaccessibility; chemical speciation; dermal contact; surface oxide; in-vitro testing; chemical speciation; cu; copper; comet assay; intracellular; ultrafine; in vitro; A549; cytotoxicity; DNA damage; nanoparticles; particle characterization; artificial sweat; nickel release; nickel powder particles; particle loadings; release kinetics; surface area; copper release; powder particles; synthetic body fluids; simulation of interstitial lung conditions; skin contact; metal release; stainless steel; particles; test method; Surface and colloid chemistry; Yt- och kolloidkemi; Analytical chemistry; Analytisk kemi; Spectroscopy; Spektroskopi;

    Sammanfattning : Do metal particles (including particles of pure metals, alloys, metal oxides and compounds) pose a hazard or risk to human health? In the light of this question, this thesis summarizes results from research conducted on metal particles, and describes the elaboration and implementation of an in vitro test methodology to study metal release from particles through corrosion and dissolution processes in synthetic biological media relevant for human exposure through inhalation/ingestion and dermal contact. Bioaccessible metals are defined as the pool of released metals from particles that potentially could be made available for absorption by humans or other organisms. LÄS MER

  3. 12. Powder degradation during powder bed fusion processing: impact of processing conditions and alloy composition

    Författare :Ahmad Raza; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; residual oxygen; powder bed fusion – electron beam; powder degradation; oxidation; Alloy 718; AlSi10Mg; powder bed fusion - laser beam; TiAl6V4; Hastelloy X.; sublimation; spatter particles; Keywords: additive manufacturing;

    Sammanfattning : In the recent decade, powder bed fusion (PBF) metal additive manufacturing (AM) has attracted huge attention both from the industry and the research community. This effort has helped mature PBF technology as a potential alternative to conventional manufacturing processes as casting, machining, forging, etc. LÄS MER

  4. 13. Surface Characteristics of Water Atomized Pre-alloyed Steel Powders and their effect on Sintering

    Författare :Dimitris Chasoglou; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spinel oxides; sintering; Cr-pre-alloyed powder; reduction; sintering atmosphere; surface oxide; fractography; XPS; oxidation; AES; EDX; carbothermal reaction; SEM; Powder metallurgy;

    Sammanfattning : Powder Metallurgy (PM) is an efficient method, in terms of cost and raw material utilization, for the production of structural parts that have strict dimensional tolerances and complex geometries. In the common processing route, steel powder is fabricated by water atomization and then pressed and sintered into the final component. LÄS MER

  5. 14. On Characterization and Optimization of Surface Topography in Additive Manufacturing Processes

    Författare :AMOGH VEDANTHA KRISHNA; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; areal surface texture parameters; additive manufacturing; power spectral density; vat-photopolymerization; laser-based Powder bed fusion; fused deposition modeling; profile parameters; feature-based characterization; and multiple regression.; scale-sensitive fractal analysis; surface metrology;

    Sammanfattning : With its ability to construct components through the layer-by-layer deposition of material, Additive Manufacturing (AM), more commonly known as "3D printing", has revolutionized the manufacturing industries. Not only can AM produce complex lightweight designs, but it can also streamline the supply chain, allowing businesses to more quickly and easily meet customer demand. LÄS MER

  7. 15. Processing Methods for Reaching Full Density Powder Metallurgical Materials

    Författare :Maheswaran Vattur Sundaram; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gas atomised powder; water atomised powder; high density powder metallurgical materials; high density; master alloys; liquid phase sintering; sintering; high velocity compaction; hot isostatic pressing; additive manufacturing;

    Sammanfattning : Powder metallurgy (PM) is one of the most cost effective methods for manufacturing structural components with complex shapes. Utilisation of the metal powder to shape the components allows to minimise material waste and increase energy efficiency. LÄS MER