Submitted by Stéfany Moreira (stemellra@yahoo.com.br) on 2013-03-06T17:04:00Z
No. of bitstreams: 1
DISEERTAÇÃO_EffectAdditionsFormation.pdf: 2939704 bytes, checksum: b8574d6fa25523b2dad22c94e5d4a45b (MD5) / Approved for entry into archive by Neide Nativa (neide@sisbin.ufop.br) on 2013-03-13T22:11:16Z (GMT) No. of bitstreams: 1
DISEERTAÇÃO_EffectAdditionsFormation.pdf: 2939704 bytes, checksum: b8574d6fa25523b2dad22c94e5d4a45b (MD5) / Made available in DSpace on 2013-03-13T22:11:16Z (GMT). No. of bitstreams: 1
DISEERTAÇÃO_EffectAdditionsFormation.pdf: 2939704 bytes, checksum: b8574d6fa25523b2dad22c94e5d4a45b (MD5)
Previous issue date: 2009 / Interstitial Free steels feature alloying elements present in an ultra low C matrix that account for C stabilization and consequently a high number of C free interstitials in a ferrite matrix that give these steels the ideal texture, low yield point, favorable plastic strain ratios, high elongation and n-value necessary for an ideal performance on forming press, drawing and stamping operations especially for automotive body part applications. This Master’s thesis indicates that Ti-stabilized IF steel substrates are more reactive than dual-stabilized IF steel substrates probably due to the presence of islands of Nb oxides at the interface between the steel substrate and the GA coating. These Nb oxides may block the Fe-Zn interdiffusion along the ferrite grain boundaries. Hence, higher reactivity rates for Ti-stabilized IF steel grades mean that this substrate is more prone than a dual-stabilized IF steel to the formation of outbursts and consequently the formation of craters, which are morphologically characterized as clusters of outbursts, whose formation mechanisms are based on capillarity effects accounting for amounts of liquid Zn being drained away from these spots. Besides, this work has also explored the typical chemistry and morphology features of craters on top of dark and light streaked areas on GA coatings, showing that there are d crystals on the bottom of craters on light streaked areas, whereas G phase was found on the bottom of craters on dark streaked areas. Also, it turns out that craters on dark streaked regions are deeper than those on light streaked areas. On top of that, the crater coverage on dark streaked regions is larger than on light streaked areas.
Identifer | oai:union.ndltd.org:IBICT/oai:localhost:123456789/2541 |
Date | January 2009 |
Creators | Storch, Breno Torezani |
Contributors | Araújo, Fernando Gabriel da Silva |
Publisher | Programa de Pós-Graduação em Engenharia de Materiais. Rede Temática em Engenharia de Materiais, Pró-Reitoria de Pesquisa e Pós-Graduação, Universidade Federal de Ouro Preto. |
Source Sets | IBICT Brazilian ETDs |
Language | English |
Detected Language | English |
Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
Source | reponame:Repositório Institucional da UFOP, instname:Universidade Federal de Ouro Preto, instacron:UFOP |
Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0028 seconds