Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFU |
Texto Completo: | https://repositorio.ufu.br/handle/123456789/33950 http://doi.org/10.14393/ufu.te.2021.5554 |
Resumo: | Hydrogen embrittlement (HE) is a phenomenon that affects many steels and other metal alloys, drastically reducing their fracture strength. Despite being studied for over a century. HE is a complex phenomenon that still needs a better understanding. Therefore, the present work aims to evaluate the influence of hardness, prior austenitic grain (PAG) size, dual-phase microstructure (DP) and environment temperature on the hydrogen embrittlement susceptibility (HES) of two high-strength low alloy (HSLA) steels: 4137-M and 4130-M. This evaluation was carried out using the Incremental Step- Loading (ISL) test, with the development of a methodology capable of identifying the fracture threshold load of low hardness steels was set as an additional objective. The results revealed that the developed methodology to identify the Pth of lower hardness steels than that recommended by the ASTM F1624 standard was valid. It was observed that the microstructure high angle boundaries (HAB) act a strong H traps, in such a way that the microstructure with high HAB density exhibited lower HES. This effect was evidenced by noticing a reduction in the HES and also in the diffusible hydrogen content in the microstructure with lower PAG size and the DP microstructure. The PAG boundary, which is a HAB, prevented part of the H from diffusing to the crack nucleation sites. For the DP microstructure, two main types of HAB were obtained, the PAG boundary and the martensite / ferrite interface, which resulted in a higher density of HAB, and, consequently, in the lower HES presented by the DP microstructure. Furthermore, the ferrite localized deformation in DP microstructure reduced the stress concentration and directed the H to ferrite, which is less susceptible than martensite. The hardness reduction decreased the steel HES, since the decrease in hardness is accompanied by lower density of H traps in the PAG boundary and greater plastic deformation capacity, factors that increase the HE resistance. Moreover, greater HES was noted at 24 °C and 4 °C, with no significant difference in HES between these two temperatures. However, at 54 °C a reduction in HES was observed. This behavior was attributed to the enhancement in H diffusivity caused by the increase in temperature, which reduced the capacity of dislocations to trap and transport hydrogen to the notch root. Finally, it was observed that H diffusion combined with the H transport by dislocations saturate the high-angle boundaries, inducing the crack to propagate through these boundaries. When the HAB were mainly the PAG boundaries, the fracture was intergranular. On the other hand, if the H-saturated HAB were the martensite packages and blocks or the martensite / ferrite interface, the fracture had a quasi-cleavage aspect. |
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Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa ligaEffect of microstructural parameters and environment temperature on the hydrogen embrittlement susceptibility of high strength low alloy steelsincremetal step loadingfragilização por hidrogênioaços de alta resistência e baixa ligamicroestruturatemperaturahydrogen embrittlementhigh strength low alloy steelsmicrostructuretemperatureCNPQ::ENGENHARIAS::ENGENHARIA MECANICAEngenharia mecânicaMetais - Fragilização por hidrogênioAço de alta resistênciaMetais e alta temperaturaMetais - MicroestruturaHydrogen embrittlement (HE) is a phenomenon that affects many steels and other metal alloys, drastically reducing their fracture strength. Despite being studied for over a century. HE is a complex phenomenon that still needs a better understanding. Therefore, the present work aims to evaluate the influence of hardness, prior austenitic grain (PAG) size, dual-phase microstructure (DP) and environment temperature on the hydrogen embrittlement susceptibility (HES) of two high-strength low alloy (HSLA) steels: 4137-M and 4130-M. This evaluation was carried out using the Incremental Step- Loading (ISL) test, with the development of a methodology capable of identifying the fracture threshold load of low hardness steels was set as an additional objective. The results revealed that the developed methodology to identify the Pth of lower hardness steels than that recommended by the ASTM F1624 standard was valid. It was observed that the microstructure high angle boundaries (HAB) act a strong H traps, in such a way that the microstructure with high HAB density exhibited lower HES. This effect was evidenced by noticing a reduction in the HES and also in the diffusible hydrogen content in the microstructure with lower PAG size and the DP microstructure. The PAG boundary, which is a HAB, prevented part of the H from diffusing to the crack nucleation sites. For the DP microstructure, two main types of HAB were obtained, the PAG boundary and the martensite / ferrite interface, which resulted in a higher density of HAB, and, consequently, in the lower HES presented by the DP microstructure. Furthermore, the ferrite localized deformation in DP microstructure reduced the stress concentration and directed the H to ferrite, which is less susceptible than martensite. The hardness reduction decreased the steel HES, since the decrease in hardness is accompanied by lower density of H traps in the PAG boundary and greater plastic deformation capacity, factors that increase the HE resistance. Moreover, greater HES was noted at 24 °C and 4 °C, with no significant difference in HES between these two temperatures. However, at 54 °C a reduction in HES was observed. This behavior was attributed to the enhancement in H diffusivity caused by the increase in temperature, which reduced the capacity of dislocations to trap and transport hydrogen to the notch root. Finally, it was observed that H diffusion combined with the H transport by dislocations saturate the high-angle boundaries, inducing the crack to propagate through these boundaries. When the HAB were mainly the PAG boundaries, the fracture was intergranular. On the other hand, if the H-saturated HAB were the martensite packages and blocks or the martensite / ferrite interface, the fracture had a quasi-cleavage aspect.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorFAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisPetrobrás - Petróleo Brasileiro S.ATese (Doutorado)A fragilização por hidrogênio (FH) é um fenômeno que afeta diversos aços e outras ligas metálicas, podendo reduzir drasticamente sua resistência à fratura. Apesar de ser estudada a mais de um século, a FH é um fenômeno complexo que ainda necessita de um melhor entendimento do seu comportamento e quais os fatores que a influenciam. Sendo assim, o presente trabalho tem como objetivo avaliar a influência da dureza, tamanho do antigo grão austenítico (AGA), microestrutura dual-phase (DP) e temperatura do meio na susceptibilidade à fragilização por hidrogênio (SFH) de dois aços de alta resistência e baixa liga (ARBL): 4137-M e 4130-M. Esta avaliação foi conduzida utilizando o teste Incremental Step-Loading (ISL) de forma que foi colocado como objetivo adicional o desenvolvimento de uma metodologia capaz de identificar a força limite de ruptura (Pth) de aços com baixa dureza. Os resultados deste trabalho revelaram que a metodologia desenvolvida para identificar o Pth de aços de baixa dureza ensaiados pelo método ISL foi válida. Os resultados mostraram ainda que os contornos de alto ângulo (CAA) da microestrutura funcionam como armadilhas fortes de H, de tal forma que a microestrutura com maior densidade de CAA exibiu a menor SFH. Este efeito foi evidenciado ao se perceber uma queda na SFH e também no teor de hidrogênio difusível nas microestruturas de menor AGA e DP. O contorno do AGA, que é um CAA, impediu que parte do H difundisse para os sítios de nucleação de trinca. Para a microestrutura DP obteve-se dois tipos de CAA principais, o contorno do AGA e a interface martensita\ferrita, que resultaram numa maior densidade de CAA, e, consequentemente, numa menor SFH apresentada pela microestrutura DP. Além disso, a deformação localizada da ferrita na microestrutura DP reduziu a concentração de tensão e direcionou a H para a ferrita, que é menos susceptível que a martensita. A redução da dureza diminuiu a SFH dos aços estudados, uma vez que a queda da dureza é acompanhada de uma menor densidade de armadilhas de H no contorno do AGA e de maior capacidade de deformar plasticamente, fatores estes que aumentam a resistência à FH. Além disso, notou-se uma maior SFH a 24 °C e 4 °C, sem diferença significativa entre estas duas temperaturas. No entanto, uma queda na SFH foi observada a 54 °C. Este comportamento foi atribuído ao aumento da difusividade do H causado pelo aumento da temperatura do meio o que diminuiu a capacidade das discordâncias de aprisionar e transportar H até a raiz do entalhe. Por fim, observou-se que difusão de H aliada ao transporte por discordâncias saturam os CAA com H induzindo a trinca a se propagar por estes contornos. Quando os CAA eram, principalmente, os contornos do AGA a fratura foi intergranular. Já, se os CAA saturados com H eram os pacotes e blocos de martensita ou a interface martensita/ferrita, a fratura tinha o aspecto de quase-clivagem.Universidade Federal de UberlândiaBrasilPrograma de Pós-graduação em Engenharia MecânicaBose Filho, Waldek Wladimirhttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785463U0&tokenCaptchar=03AGdBq25kBXRE5Te6LLbq3VWHkuOnsFFC1SAC0knJlqTmPNRTSDrvCmbBohJw7mcsi0B2QFkoYcLNUIvh3puEiioWvWv1o1eBX7zydA4biuNdQ-gR7kr65wpVD2c-WBjae_UZb4bTFgDRd7wqJQEQ1CfFfZzW6Pt0-_JEUBSBWIwdbn7kJ66CFu15AQ2J_bZCP5xSETo__7ZiUcP75YrTU4O9Af3U1zvgIIXXOWoMf0fXN_sL9OCSlU-1jAlPb-GYBk812XUKvO2gvhzXiFEJO_cxEoCSnSUacQoM3p90R1msW7Aig_WH_qy_PZ1PAHfqgROCpegj5TH_AdBh530-6y7TOSWJ4bj6_46Bt5UQx4BT-xFFTr4o8WnpW9nP1t_PzAxg5a0ZOxe73j9eNyQUbGbARjjanaxRWzlL33BYcvVU3px-UolWmB4yC2ALkaDQ0bVvGmKhhJmBkZTi6RhMt5fKBw0RwO2_RgFranco, Sinésio Domingueshttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4786105Z3&tokenCaptchar=03AGdBq25wE4gjYQOmVCr23n1b0tRl5yzYoI5IKUCaeA4JuCjvqGZu6jPLLoTnq-6rzvKjCz8GsDMHlM-GbsVKd0BPl3I9T4U5CBM-mQMOtQ0w_tf-Un0DlcV2GupS1w7mWItwWuY0lDdBRnpQr4Ub-LomYjPfF_bxlZ0ElG1_rIVAM-mDfximh0BYO4UQK1-mo2R7OEX5cwqhMUNYabzvciuHA7AtSc2lQRqe0WTUKb4tnbb0Zbig5HWgq8txDIime1WqHhlrgBIASR7JJB_pVOIIqsB6CTKd1d1SBTxj_0Lw7UyeeYDmyDoOsNheQT67k-rPQkYd9wntRCNwZYmSauGZVFsSspBFDq2a3kfP0yWDMYmoCz4DwZblxxU_11eBA3Pun-QugqfNjizGmSqXg_gyre_ugcbVJ6D2Yh0Fnq_QuFcCxzsrKkYkiRo_lRNaUCHisJjXIDb5S3gOf3c7m4jd8S8qxQWHOQViarinho, Louriel Oliveirahttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4707975Z6&tokenCaptchar=03AGdBq26BCUAkFGqPCf2mIWqTk8CGreCbYv_J0bR5MsFkWopT6TVV_yyjVyfN7CyUZ22Ztgp2CFOzIoKOxlff5g76rh7gonDCFbBmGeaGzl0hVaAJyH-4F_nglkZgjyO5fy8vsGtGQSsOR8_pJw1ijHcPpmT0jT2tClIhLKeijOjAvwYlibvnrDnPG6KydiLEiGhRkrDh4FYhXMb4XMYtTXbKXlAI97NN6q3yU6HCgMP4gm7WqHMU0zyXu7CMgemyoijsWhy23bqR0HbZNuWSyIyK8A4uuFmzVk3jEFgn-kh4lOcL7V6gB2cu3AMmRgUWcwhSX-vJiYZlZphDwa0TyJl8MBJIWCH7vn-rMYNrD8czZesDaHzfIAFXNonRG8ny2aZaAfmwREawltPLadq8RLzV-ZoSFiq7xf_tzkYR6bIaDLv1ERryZHQqKMqBY8pTQh0LL2aI5V8GtGRj7jbn6cQa878IJn7ScwArencibia, Rosenda Valdéshttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4768031U8&tokenCaptchar=03AGdBq26QoGOHZRPY7Tlh3wiI9nUUUZbaQ4RCAWulrPbcdJ7Pn1RTqIPdB5RB3iUDrfvfuq00AhQ8bSHgPCJcRa3nuKa8QP0GTS_mcsL5ZgPxRGjDHqhLy2hXy0ayWhwGh0qabMlwQOwSvdbxNeSXHvjQ26zuvd1wU8tXq415MbROFouR3Dg2HEJdFkV5lqCAAzsxlWofxwEZ9dDkW3tlfCEtX-E4u1JKA-3Ce6YFgqaxrdo8meLDugrW3VWgbb24eWBYWid9dvFTR1txA2EqSw6E4aB1ce6ZywE7rcbCu6FFAI_FcE5UNPSE4IG_E--xBmrA4lmDSWc3LVGhjj2qNOrSqwfsOyilQSL7TgfZSgNJpifLLBxnELE6UQeTb7TXIJ3_NI9VHhs-WzQ25-VgssOEG7P0o3dY1eNGChUVos7UHOSnhNqZaU9XxlbpscloJDv0ga9hVL5rz01LfBFf6YHiEMKh_ThBygOliveira, Ana Sofia Clímaco Monteiro dehttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4794275P7&tokenCaptchar=03AGdBq27lC9rF2j4Mi46M1mH3ukhPvbrWnLrga5MB_44E2CKos1p-BMG3oA1I9QZ_K7s1C4OOl6CTryG_9WqtMIqgw8aifk36QJ9JbaDhfvtZnuASxOZmZxzqlAZDv_di27XmUEFZxanQqjrn-XdMeNZzB2neUTBS86hP7wnSAU8L6FORJ3dACbPjJLoFxxOa3xJGpEKaBZWtKhHvlh0jZI-4uiGCF7WpG7RBZJIza1YaM_P7CsDjDivg7bVDUfKrnRu84doxR6TXmuof6X4EjscwNd9Y16337HfRrF-oNWL_aexHhiXGvSA0EV-EeSwsilycQ_ltLcrqflylPPBt5QvjQY65g3Purw2yLI9J697HQ516NkFUIe7cUInRJxcGK55URLie8LnC3r4sHcKfmGDcN7tZc-4rxAqe6N9918ehR5ll6mzCAjFSKISXObj1HfVZlpcqqZEER55BWZhwsJ42BJvf_fjWzwPaes, Marcelo Torres Pizahttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785025H5&tokenCaptchar=03AGdBq24Ta63FqPeMrkeHnj6BR9mw8o8geSzL3v9kzmi4iavtEpL48NHAF-XkZD7o4JZzR2TJlVj1Rs8KF2t3XxvJdPhG5VY8c50OeRZPGJ-MvNlmFWwavwSMZJzjiRrih0UxjrfKDxtFJ9OhBia9ehQ18UgPuyhI9s2uX7Rtr0dDwbwAHzyd5Pwosf1TO7GaFtvzP2OjHmBcGs0hiUJ9RDzst9j4PGv_0V7--uRlyZ1a6xoLZUP7P7wYjmruBe7g2HR5g4r0_ye4RS2ySaf8cY9v66S-2k2t2gdzrx8dTbk1hccc5TtmCY-Krm0qFTldfXx3r3v2qgwxHGbP8tAs_sVsZLMiluAUEIChaD_OgqvcfozqJaJBgUQBcWY3u3e-38sBw7RIdogx94EveZ1v_0gLnLW8DKWFmC3iZYSlBsw2lOWO0dTk_JADpLH1aP6r1ihFhOSumevrYI-VahHvyzsaLpvzSXN_MwMartiniano, Guilherme Antonelli2022-01-14T17:58:16Z2022-01-14T17:58:16Z2021-11-05info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfMARTINIANO, Guilherme Antonelli. Efeito de Parâmetros Microestruturais e da Temperatura do Meio na Susceptibilidade à Fragilização por Hidrogênio de Aços de Alta Resistência e Baixa Liga. 2021. 247 f. Tese (Doutorado em Engenharia Mecânica) - Universidade Federal de Uberlândia, Uberlândia, 2021. DOI https://doi.org/10.14393/ufu.te.2021.5554https://repositorio.ufu.br/handle/123456789/33950http://doi.org/10.14393/ufu.te.2021.5554porinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFUinstname:Universidade Federal de Uberlândia (UFU)instacron:UFU2022-01-15T06:20:26Zoai:repositorio.ufu.br:123456789/33950Repositório InstitucionalONGhttp://repositorio.ufu.br/oai/requestdiinf@dirbi.ufu.bropendoar:2022-01-15T06:20:26Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU)false |
dc.title.none.fl_str_mv |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga Effect of microstructural parameters and environment temperature on the hydrogen embrittlement susceptibility of high strength low alloy steels |
title |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
spellingShingle |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga Martiniano, Guilherme Antonelli incremetal step loading fragilização por hidrogênio aços de alta resistência e baixa liga microestrutura temperatura hydrogen embrittlement high strength low alloy steels microstructure temperature CNPQ::ENGENHARIAS::ENGENHARIA MECANICA Engenharia mecânica Metais - Fragilização por hidrogênio Aço de alta resistência Metais e alta temperatura Metais - Microestrutura |
title_short |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
title_full |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
title_fullStr |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
title_full_unstemmed |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
title_sort |
Efeito de parâmetros microestruturais e da temperatura do meio na susceptibilidade à fragilização por hidrogênio de aços de alta resistência e baixa liga |
author |
Martiniano, Guilherme Antonelli |
author_facet |
Martiniano, Guilherme Antonelli |
author_role |
author |
dc.contributor.none.fl_str_mv |
Bose Filho, Waldek Wladimir http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785463U0&tokenCaptchar=03AGdBq25kBXRE5Te6LLbq3VWHkuOnsFFC1SAC0knJlqTmPNRTSDrvCmbBohJw7mcsi0B2QFkoYcLNUIvh3puEiioWvWv1o1eBX7zydA4biuNdQ-gR7kr65wpVD2c-WBjae_UZb4bTFgDRd7wqJQEQ1CfFfZzW6Pt0-_JEUBSBWIwdbn7kJ66CFu15AQ2J_bZCP5xSETo__7ZiUcP75YrTU4O9Af3U1zvgIIXXOWoMf0fXN_sL9OCSlU-1jAlPb-GYBk812XUKvO2gvhzXiFEJO_cxEoCSnSUacQoM3p90R1msW7Aig_WH_qy_PZ1PAHfqgROCpegj5TH_AdBh530-6y7TOSWJ4bj6_46Bt5UQx4BT-xFFTr4o8WnpW9nP1t_PzAxg5a0ZOxe73j9eNyQUbGbARjjanaxRWzlL33BYcvVU3px-UolWmB4yC2ALkaDQ0bVvGmKhhJmBkZTi6RhMt5fKBw0RwO2_Rg Franco, Sinésio Domingues http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4786105Z3&tokenCaptchar=03AGdBq25wE4gjYQOmVCr23n1b0tRl5yzYoI5IKUCaeA4JuCjvqGZu6jPLLoTnq-6rzvKjCz8GsDMHlM-GbsVKd0BPl3I9T4U5CBM-mQMOtQ0w_tf-Un0DlcV2GupS1w7mWItwWuY0lDdBRnpQr4Ub-LomYjPfF_bxlZ0ElG1_rIVAM-mDfximh0BYO4UQK1-mo2R7OEX5cwqhMUNYabzvciuHA7AtSc2lQRqe0WTUKb4tnbb0Zbig5HWgq8txDIime1WqHhlrgBIASR7JJB_pVOIIqsB6CTKd1d1SBTxj_0Lw7UyeeYDmyDoOsNheQT67k-rPQkYd9wntRCNwZYmSauGZVFsSspBFDq2a3kfP0yWDMYmoCz4DwZblxxU_11eBA3Pun-QugqfNjizGmSqXg_gyre_ugcbVJ6D2Yh0Fnq_QuFcCxzsrKkYkiRo_lRNaUCHisJjXIDb5S3gOf3c7m4jd8S8qxQWHOQ Viarinho, Louriel Oliveira http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4707975Z6&tokenCaptchar=03AGdBq26BCUAkFGqPCf2mIWqTk8CGreCbYv_J0bR5MsFkWopT6TVV_yyjVyfN7CyUZ22Ztgp2CFOzIoKOxlff5g76rh7gonDCFbBmGeaGzl0hVaAJyH-4F_nglkZgjyO5fy8vsGtGQSsOR8_pJw1ijHcPpmT0jT2tClIhLKeijOjAvwYlibvnrDnPG6KydiLEiGhRkrDh4FYhXMb4XMYtTXbKXlAI97NN6q3yU6HCgMP4gm7WqHMU0zyXu7CMgemyoijsWhy23bqR0HbZNuWSyIyK8A4uuFmzVk3jEFgn-kh4lOcL7V6gB2cu3AMmRgUWcwhSX-vJiYZlZphDwa0TyJl8MBJIWCH7vn-rMYNrD8czZesDaHzfIAFXNonRG8ny2aZaAfmwREawltPLadq8RLzV-ZoSFiq7xf_tzkYR6bIaDLv1ERryZHQqKMqBY8pTQh0LL2aI5V8GtGRj7jbn6cQa878IJn7Scw Arencibia, Rosenda Valdés http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4768031U8&tokenCaptchar=03AGdBq26QoGOHZRPY7Tlh3wiI9nUUUZbaQ4RCAWulrPbcdJ7Pn1RTqIPdB5RB3iUDrfvfuq00AhQ8bSHgPCJcRa3nuKa8QP0GTS_mcsL5ZgPxRGjDHqhLy2hXy0ayWhwGh0qabMlwQOwSvdbxNeSXHvjQ26zuvd1wU8tXq415MbROFouR3Dg2HEJdFkV5lqCAAzsxlWofxwEZ9dDkW3tlfCEtX-E4u1JKA-3Ce6YFgqaxrdo8meLDugrW3VWgbb24eWBYWid9dvFTR1txA2EqSw6E4aB1ce6ZywE7rcbCu6FFAI_FcE5UNPSE4IG_E--xBmrA4lmDSWc3LVGhjj2qNOrSqwfsOyilQSL7TgfZSgNJpifLLBxnELE6UQeTb7TXIJ3_NI9VHhs-WzQ25-VgssOEG7P0o3dY1eNGChUVos7UHOSnhNqZaU9XxlbpscloJDv0ga9hVL5rz01LfBFf6YHiEMKh_ThByg Oliveira, Ana Sofia Clímaco Monteiro de http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4794275P7&tokenCaptchar=03AGdBq27lC9rF2j4Mi46M1mH3ukhPvbrWnLrga5MB_44E2CKos1p-BMG3oA1I9QZ_K7s1C4OOl6CTryG_9WqtMIqgw8aifk36QJ9JbaDhfvtZnuASxOZmZxzqlAZDv_di27XmUEFZxanQqjrn-XdMeNZzB2neUTBS86hP7wnSAU8L6FORJ3dACbPjJLoFxxOa3xJGpEKaBZWtKhHvlh0jZI-4uiGCF7WpG7RBZJIza1YaM_P7CsDjDivg7bVDUfKrnRu84doxR6TXmuof6X4EjscwNd9Y16337HfRrF-oNWL_aexHhiXGvSA0EV-EeSwsilycQ_ltLcrqflylPPBt5QvjQY65g3Purw2yLI9J697HQ516NkFUIe7cUInRJxcGK55URLie8LnC3r4sHcKfmGDcN7tZc-4rxAqe6N9918ehR5ll6mzCAjFSKISXObj1HfVZlpcqqZEER55BWZhwsJ42BJvf_fjWzw Paes, Marcelo Torres Piza http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785025H5&tokenCaptchar=03AGdBq24Ta63FqPeMrkeHnj6BR9mw8o8geSzL3v9kzmi4iavtEpL48NHAF-XkZD7o4JZzR2TJlVj1Rs8KF2t3XxvJdPhG5VY8c50OeRZPGJ-MvNlmFWwavwSMZJzjiRrih0UxjrfKDxtFJ9OhBia9ehQ18UgPuyhI9s2uX7Rtr0dDwbwAHzyd5Pwosf1TO7GaFtvzP2OjHmBcGs0hiUJ9RDzst9j4PGv_0V7--uRlyZ1a6xoLZUP7P7wYjmruBe7g2HR5g4r0_ye4RS2ySaf8cY9v66S-2k2t2gdzrx8dTbk1hccc5TtmCY-Krm0qFTldfXx3r3v2qgwxHGbP8tAs_sVsZLMiluAUEIChaD_OgqvcfozqJaJBgUQBcWY3u3e-38sBw7RIdogx94EveZ1v_0gLnLW8DKWFmC3iZYSlBsw2lOWO0dTk_JADpLH1aP6r1ihFhOSumevrYI-VahHvyzsaLpvzSXN_Mw |
dc.contributor.author.fl_str_mv |
Martiniano, Guilherme Antonelli |
dc.subject.por.fl_str_mv |
incremetal step loading fragilização por hidrogênio aços de alta resistência e baixa liga microestrutura temperatura hydrogen embrittlement high strength low alloy steels microstructure temperature CNPQ::ENGENHARIAS::ENGENHARIA MECANICA Engenharia mecânica Metais - Fragilização por hidrogênio Aço de alta resistência Metais e alta temperatura Metais - Microestrutura |
topic |
incremetal step loading fragilização por hidrogênio aços de alta resistência e baixa liga microestrutura temperatura hydrogen embrittlement high strength low alloy steels microstructure temperature CNPQ::ENGENHARIAS::ENGENHARIA MECANICA Engenharia mecânica Metais - Fragilização por hidrogênio Aço de alta resistência Metais e alta temperatura Metais - Microestrutura |
description |
Hydrogen embrittlement (HE) is a phenomenon that affects many steels and other metal alloys, drastically reducing their fracture strength. Despite being studied for over a century. HE is a complex phenomenon that still needs a better understanding. Therefore, the present work aims to evaluate the influence of hardness, prior austenitic grain (PAG) size, dual-phase microstructure (DP) and environment temperature on the hydrogen embrittlement susceptibility (HES) of two high-strength low alloy (HSLA) steels: 4137-M and 4130-M. This evaluation was carried out using the Incremental Step- Loading (ISL) test, with the development of a methodology capable of identifying the fracture threshold load of low hardness steels was set as an additional objective. The results revealed that the developed methodology to identify the Pth of lower hardness steels than that recommended by the ASTM F1624 standard was valid. It was observed that the microstructure high angle boundaries (HAB) act a strong H traps, in such a way that the microstructure with high HAB density exhibited lower HES. This effect was evidenced by noticing a reduction in the HES and also in the diffusible hydrogen content in the microstructure with lower PAG size and the DP microstructure. The PAG boundary, which is a HAB, prevented part of the H from diffusing to the crack nucleation sites. For the DP microstructure, two main types of HAB were obtained, the PAG boundary and the martensite / ferrite interface, which resulted in a higher density of HAB, and, consequently, in the lower HES presented by the DP microstructure. Furthermore, the ferrite localized deformation in DP microstructure reduced the stress concentration and directed the H to ferrite, which is less susceptible than martensite. The hardness reduction decreased the steel HES, since the decrease in hardness is accompanied by lower density of H traps in the PAG boundary and greater plastic deformation capacity, factors that increase the HE resistance. Moreover, greater HES was noted at 24 °C and 4 °C, with no significant difference in HES between these two temperatures. However, at 54 °C a reduction in HES was observed. This behavior was attributed to the enhancement in H diffusivity caused by the increase in temperature, which reduced the capacity of dislocations to trap and transport hydrogen to the notch root. Finally, it was observed that H diffusion combined with the H transport by dislocations saturate the high-angle boundaries, inducing the crack to propagate through these boundaries. When the HAB were mainly the PAG boundaries, the fracture was intergranular. On the other hand, if the H-saturated HAB were the martensite packages and blocks or the martensite / ferrite interface, the fracture had a quasi-cleavage aspect. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-11-05 2022-01-14T17:58:16Z 2022-01-14T17:58:16Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
MARTINIANO, Guilherme Antonelli. Efeito de Parâmetros Microestruturais e da Temperatura do Meio na Susceptibilidade à Fragilização por Hidrogênio de Aços de Alta Resistência e Baixa Liga. 2021. 247 f. Tese (Doutorado em Engenharia Mecânica) - Universidade Federal de Uberlândia, Uberlândia, 2021. DOI https://doi.org/10.14393/ufu.te.2021.5554 https://repositorio.ufu.br/handle/123456789/33950 http://doi.org/10.14393/ufu.te.2021.5554 |
identifier_str_mv |
MARTINIANO, Guilherme Antonelli. Efeito de Parâmetros Microestruturais e da Temperatura do Meio na Susceptibilidade à Fragilização por Hidrogênio de Aços de Alta Resistência e Baixa Liga. 2021. 247 f. Tese (Doutorado em Engenharia Mecânica) - Universidade Federal de Uberlândia, Uberlândia, 2021. DOI https://doi.org/10.14393/ufu.te.2021.5554 |
url |
https://repositorio.ufu.br/handle/123456789/33950 http://doi.org/10.14393/ufu.te.2021.5554 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Uberlândia Brasil Programa de Pós-graduação em Engenharia Mecânica |
publisher.none.fl_str_mv |
Universidade Federal de Uberlândia Brasil Programa de Pós-graduação em Engenharia Mecânica |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFU instname:Universidade Federal de Uberlândia (UFU) instacron:UFU |
instname_str |
Universidade Federal de Uberlândia (UFU) |
instacron_str |
UFU |
institution |
UFU |
reponame_str |
Repositório Institucional da UFU |
collection |
Repositório Institucional da UFU |
repository.name.fl_str_mv |
Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU) |
repository.mail.fl_str_mv |
diinf@dirbi.ufu.br |
_version_ |
1805569699504717824 |