Sökning: "powder particles"

Visar resultat 1 - 5 av 162 avhandlingar innehållade orden powder particles.

  1. 1. 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

  2. 2. Powder degradation during powder bed fusion processing

    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; Laser-based powder bed fusion; Alloy 718; Powder degradation; Oxidation; Electron beam powder bed fusion; Additive manufacturing; AlSi10Mg; Residual oxygen; Spatter particles; Sublimation.;

    Sammanfattning : Powder bed fusion (PBF) techniques, including laser-based powder bed fusion (LB-PBF) and electron beam powder bed fusion (EB-PBF), are two rapidly growing additive manufacturing (AM) processes due to their ability to produce complex geometries in near-net shapes. To attain reproducibility and repeatability in PBF processes, a consistent set of powder properties is vital. LÄS MER

  3. 3. Metal release from powder particles in synthetic biological media

    Författare :Klara Midander; Jinshan Pan; Mats Norell; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; metal release; stainless steel; Cu; powder particles; synthetic body fluids; test method; in vitro tests; Other materials science; Övrig teknisk materialvetenskap;

    Sammanfattning : Humans are exposed to metals and metal-containing materials daily, either conscious, e.g. using metal tools or objects, or unconscious, e.g. LÄS MER

  4. 4. 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

  5. 5. Confined Compression of Single Particles : Development of a Novel Triaxial Testing Instrument and Particle-Scale Modelling

    Författare :Henrik Jonsson; Göran Frenning; Göran Alderborn; Abderrahim Michrafy; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Powder compaction; Compression; Single particle; Particle mechanics; Powder mechanics; Confined conditions; Triaxial; Apparatus design; Modelling; Galenisk farmaci; Pharmaceutics;

    Sammanfattning : When predicting the performance of a powder compaction process, assessing the behaviour of the particles comprising the powder bed is of central relevance. Currently, however, no experimental methods are available for mimicking the multiaxial loading conditions imposed on the individual particles in a powder bed during compaction, and such analyses are therefore usually performed in silico. LÄS MER