Microstructural changes caused by yttrium addition to NbTi-modified centrifugally cast HP-type stainless steels

Nunes, Fábio Carvalho; Almeida, Luiz Henrique de; Dille, Jean; Delplancke, Jean‐Luc; May, Iain

doi:10.1016/j.matchar.2006.04.007

Cited by 71 publications

(25 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…With the continuous technological improvement throughout the last 70 years [7][8][9][10][11], a new grade of austenitic stainless steel, HP40 (25 % Cr and 35 % Ni), has been developed for the steam reforming process. The most popular material used in steam reforming is HP Micro Alloy (HP-MA), a new micro-alloyed steel with additions of Ti (precipitation strengthening) [12], Nb (high temperature structural stability and grain boundary anti-sliding performance) [13], W (solid solution strengthening) [14] or rare earth elements (to improve high temperature oxidation resistance) [15,16].…”

Section: Introductionmentioning

confidence: 99%

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Wang

Flahaut

Zhu

et al. 2019

Journal of Alloys and Compounds

View full text Add to dashboard Cite

The transformation from M 7 C 3 → M 23 C 6 in a high performance micro alloy (HP-MA) was studied using different techniques. Following the cooling during the centrifugal casting, the as-cast HP-MA alloy consists of an austenitic matrix with the primary carbide network consisting of a combination of M 7 C 3 (M being mainly chromium) and MC (M being mainly niobium). During the heat treatment at 1000 o C, the primary chromium carbides transform from M 7 C 3 to M 23 C 6. The incompletely transformed primary carbide consists of an outer shell of M 23 C 6 carbide (coherent with the austenitic matrix) and a core of M 7 C 3 type carbide. The experimentally determined M23C6 shell thickness agrees reasonably well with the estimated diffusion distance of carbon in M 23 C 6 based on Zener's relation implying that the M 7 C 3 → M 23 C 6 transformation is mainly controlled by the diffusion of the carbon from M 7 C 3 to the matrix through the M 23 C 6 shell. This mechanism is discussed vis-à-vis the literature reported mechanism on the transformation.

show abstract

Section: Introductionmentioning

confidence: 99%

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Wang

Flahaut

Zhu

et al. 2019

Journal of Alloys and Compounds

View full text Add to dashboard Cite

show abstract

“…Therefore, yttrium can purify the superalloy by reducing the sulphide and oxide. 11,12 However, the effect of Y on oxidation property at elevated temperature for IN 713C alloy has not been considered. Therefore, the purpose of the present work is to investigate the desirable effect of yttrium addition on high-temperature performances in IN 713C alloy.…”

Section: Introductionmentioning

confidence: 99%

Influence of yttrium addition on stress rupture property and oxidation resistance of Inconel 713C at high temperature

Kang

Woo

Lee

et al. 2015

Materials Research Innovations

View full text Add to dashboard Cite

The influence of yttrium addition on high-temperature performance of stress rupture property and oxidation resistance in Inconel 713C has been investigated. High-temperature stress rupture property and oxidation resistance property of Inconel 713C were dramatically improved with increasing yttrium addition content up to 0·02%yttrium, then decreased in excess of yttrium. Especially, the carbide morphology changed to discrete blocky shapes by causing improved high-temperature properties. Intermetallic compounds by excess yttrium addition made a poor stress rupture life. The high-temperature oxidation resistance of 0·02 wt-% yttrium added Inconel 713C improved more than no added yttrium Inconel 713C.

show abstract

“…Tal como outras ligas, os aços inoxidáveis classificam-se como fundidos e trabalhados, sendo que estes últimos sofrem conformação mecânica para o condicionamento estrutural, antes da obtenção da forma final. Os aços inoxidáveis fundidos da série H, quando aplicados em temperaturas acima de 650 0 C, devido ao alto teor de carbono em sua composição química apresentam uma evolução microestrutural conforme a temperatura de serviço aumenta e, desta forma, mantém a sua elevada resistência mecânica, particularmente sob o ponto de vista da resistência a fluência [1]. Entre os aços inoxidáveis fundidos resistentes a altas temperaturas destacam-se os graus HK e HP, que são extensivamente usados em aplicações estruturais em temperaturas de até 1150 0 C, mantendo boa resistência à corrosão por gases quentes.…”

Section: Introductionunclassified

Propagação De Trinca Por Fluência No Aço Astm a 297 Gr Hp Modificado Com Nióbio

Gatti¹,

Ruchert²,

Bueno³

et al. 2014

ABM Proceedings

View full text Add to dashboard Cite

ResumoEste trabalho tem por objetivo aplicar o conceito teórico e experimental fornecido pela mecânica da fratura dependente do tempo, para avaliar por meio do parâmetro de fratura C* suscetibilidade do aço ASTM A297 Gr HP-Nb, para resistir à propagação de trincas por fluência. Este aço é utilizado na fabricação de colunas de suporte de tubos radiantes de Unidades de Coqueamento Retardado, que operam por longos períodos de tempo em temperaturas elevadas. Os ensaios de fluência convencional e de propagação de trinca por fluência foram realizados na temperatura de 927°C, de acordo com as recomendações das normas ASTM E139-11 e ASTM E1457-13. Dos resultados das curvas de fluência obtida para diferentes valores de tensões aplicadas foram determinadas as constantes, A e n, da relação de Norton. Com os resultados obtidos da taxa de propagação de trinca por fluência, da/dt, em função do parâmetro C*, foi possível ser modelada a equação da/dt = 1,1x10 -3 (C*) 0,78 . A morfologia da fratura observada na região de crescimento de trinca por fluência no estado estacionário apresentou modo de propagação interdentrítica, típica de aços com estrutura austenítica bruta de fusão. Palavras-chave: Fluência; Propagação de trinca por fluência; Aço ASTM A297-Nb; Integral-C*. CREEP CRACK PROPAGATION OF NIOBIUM MODIFIED ASTM A-297 GR HP STEEL AbstractThis work aims to apply the theoretical and experimental concepts provided by timedependent fracture mechanics to assess, by means of fracture parameter C*, the ability of steel ASTM A297 Gr HP modified with Niobium, to resist creep crack propagation. This material is used in the manufacture of steel support columns of radiant tubes of Retarded Coking Units to operate for long periods of time at high temperatures. The tests of conventional creep and creep crack propagation were held in the temperature of 927°C, in accordance to ASTM E139-11 and E1457-13. From the results of creep curves obtained for different values of applied stress were determined the constants, A and n, from Norton relationship. With the results obtained from the creep crack propagation rate da/dt as a function of the parameter C*, the equation da/dt=1,1x10 -3 (C*) 0.78 could be modeled. Fracture morphology presented interdendritic propagation features in the steady-state creep region, typical of steels presenting as-cast austenitic structure.

show abstract

Microstructural changes caused by yttrium addition to NbTi-modified centrifugally cast HP-type stainless steels

Cited by 71 publications

References 17 publications

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Influence of yttrium addition on stress rupture property and oxidation resistance of Inconel 713C at high temperature

Propagação De Trinca Por Fluência No Aço Astm a 297 Gr Hp Modificado Com Nióbio

Contact Info

Product

Resources

About

Microstructural changes caused by yttrium addition to NbTi-modified centrifugally cast HP-type stainless steels

Cited by 71 publications

References 17 publications

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Influence of yttrium addition on stress rupture property and oxidation resistance of Inconel 713C at high temperature

Propagação De Trinca Por Fluência No Aço Astm a 297 Gr Hp Modificado Com Nióbio

Contact Info

Product

Resources

About

Primary carbide transformation in a high performance micro-alloy at 1000 °C

Primary carbide transformation in a high performance micro-alloy at 1000 °C