Nickel and cobalt-based superalloys with a \u03b3-\u03b3' microstructure are known for their excellent creep resistance at high temperatures. Their microstructure is engineered using different alloying elements, that partition either to the fcc \u03b3 matrix or to the ordered \u03b3' phase. In the present work the effect of alloying elements on their segregation behaviour in nickel-based superalloys, diffusion in cobalt-based superalloys and the temperature dependent solid solution strengthening in nickel-based alloys is investigated. The effect of dendritic segregation on the local mechanical properties of individual phases in the as-cast, heat treated and creep deformed state of a nickel-based superalloy is investigated. The local chemical composition is characterized using Electron Probe Micro Analysis and then correlated with the mechanical properties of individual phases using nanoindentation. Furthermore, the temperature dependant solid solution hardening contribution of Ta, W & Re towards fcc nickel is studied. The room temperature hardening is determined by a diffusion couple approach using nanoindentation and energy dispersive X-ray analysis for relating hardness to the chemical composition. The high temperature properties are determined using compression strain rate jump tests. The results show that at lower temperatures, the solute size is prevalent and the elements with the largest size difference with nickel, induce the greatest hardening consistent with a classical solid solution strengthening theory. At higher temperatures, the solutes interact with the dislocations such that the slowest diffusing solute poses maximal resistance to dislocation glide and climb. Lastly, the diffusion of different technically relevant solutes in fcc cobalt is investigated using diffusion couples. The results show that the large atoms diffuse faster in cobalt-based superalloys similar to their nickel-based counterparts.<\/p>","protected":false},"excerpt":{"rendered":"
Nickel- und Cobaltbasissuperlegierungen mit \u03b3-\u03b3‘ mikrostruktur sind f\u00fcr ihre exzellente Kriechbest\u00e4ndigkeit bei hohen Temperaturen bekannt. Ihre Mikrostruktur wird \u00fcber verschiedene Legierungselemente eingestellt, welche sich entweder in der fcc \u03b3 Matrix oder der geordneten \u03b3‘ Phase anreichern. In der vorliegenden Arbeit wurde das Segregationsverhalten verschiedener Legierungselemente in Nickelbasissuperlegierungen, deren Diffusivit\u00e4t in Kobaltbasislegierungen und die temperaturabh\u00e4ngige Mischkristallh\u00e4rtung […]<\/p>\n","protected":false},"featured_media":2599,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[],"product_cat":[58],"product_tag":[],"class_list":{"0":"post-1837","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-fau-studien-materialwissenschaft-und-werkstofftechnik","7":"has-post-title","8":"has-post-date","9":"has-post-category","10":"has-post-tag","11":"has-post-comment","12":"has-post-author","13":"","15":"first","16":"instock","17":"taxable","18":"shipping-taxable","19":"purchasable","20":"product-type-simple"},"acf":{"autor":"Ur Rehman, Hamad","orcid":"","ror":"","herausgeber":"","orcid_hrsg":"","rorhrsg":"","bearbeiter":"","sonstige_beteiligte_personen":"","untertitel":"","zusatz":"","jahr":"2016","zeitschrift":"","serie":"","serie_name":"","serie_band":"","serie_jahr":"","serie_titel_band":"","vortrage":"","issn":"","isbn":"","isbn13":"978-3-944057-71-2","seiten":"iii, 140","sonstiges":"Ill., graph. Darst.","band":8,"auflage":"","opus":"","dspace":"7407","e-isbn_pdf":"978-3-944057-72-9","doi":"","epub":"","e-isbn_epub":"","doi_epub":"","html":"","e-isbn_html":"","doi_html":"","e-isbn_reader":"","doi_reader":"","digibib":"","urn":"urn:nbn:de:bvb:29-opus4-74073","supplementary_material":"","sprache":["Englisch"],"ausgabe":"Softcover","suche":" 9783944057712 9783944057729 ","lizenz":"BY-NC-ND-3","bemerkung":""},"builder_content":"","_links":{"self":[{"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/product\/1837","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/comments?post=1837"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/media\/2599"}],"wp:attachment":[{"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/media?parent=1837"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/product_brand?post=1837"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/product_cat?post=1837"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.university-press.fau.de\/en\/wp-json\/wp\/v2\/product_tag?post=1837"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}