Effect of weld metal chemistry and heat input on the structure and properties of duplex stainless steel welds
15 Oct 2003-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing (Elsevier)-Vol. 358, Iss: 1, pp 9-16
TL;DR: In this article, a low heat input process viz., EBW and another commonly employed process, gas tungsten-arc welding have been employed for welding of duplex stainless steels with and without nickel enhancement.
Abstract: The excellent combination of strength and corrosion resistance in duplex stainless steels (DSS) is due to their strict composition control and microstructural balance. The ferrite–austenite ratio is often upset in DSS weld metals owing to the rapid cooling rates associated with welding. To achieve the desired ferrite–austenite balance and hence properties, either the weld metal composition and/or the heat input is controlled. In the current work, a low heat input process viz., EBW and another commonly employed process, gas tungsten-arc welding have been employed for welding of DSS with and without nickel enhancement. Results show that (i) chemical composition has got a greater influence on the ferrite–austenite ratio than the cooling rate, (ii) and even EBW which is considered an immature process in welding of DSS, can be employed provided means of filler addition could be devised.
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TL;DR: In this paper, the important factors of material and environmental conditions on decomposition of super duplex stainless steels in chloride content were studied and the results obtained after these experiments will have an important influence in relations of recognizing the composite structures, manufacture methods, microstructures, and environmental situations that may help to reduce to mitigate decomposition in chloride solutions on weld regions.
Abstract: In this paper work, its cover the important factors of material and environmental conditions on decomposition of super duplex stainless steels in chloridecontent were studied. Variations in the SDSS structural changes by heat treatment and cyclic heat treatmentsat 600°C were investigated in terms of deviations in the proportion of austenite and ferrite segments, phase morphology and intermetallic precipitation using SEM. Alloy structure and chemical composition of weldment and annealed weldment in chloride solution composition was also found to affect the corrosion performance and passivation of SDSS. Corrosion rates and susceptibility of DSS was observed with addition of chloride solutions.The result obtained after these experiments will have an important influence in relations of recognizing the composite structures, manufacturemethods, microstructures, and environmental situations that may be help to reduce to mitigate decomposition of SDSS in chloride solutions on weld regions.
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TL;DR: In this article, the hot work character of stainless steel is focused on and the technique and operation of heating process of Stainless steel are studied in the aspects of the charging of steel heating furnace, the temperature regulation and control in steel heating process, the detection and control of furnace temperature and heating time, the control of atmosphere and furnace pressure during heating process and the controlling of furnace when rolling stopped.
Abstract: Hot work character of stainless steel is focused on and the technique and operation of heating process of stainless steel are studied in this paper in the aspects of the charging of stainless steel heating furnace, the temperature regulation and control in steel heating process, the detection and control of furnace temperature and heating time, the control of atmosphere and furnace pressure during heating process, and the control of furnace when rolling stopped, etc. And each of them has significant effect on the production of stainless steel.
01 Jan 2011
TL;DR: In this paper, a trabalho tem como objetivo analisar a influencia da restricao no balanceamento de fases, na morfologia da austenita, na microdureza, and na tenacidade da Zona Afetada pelo Calor (ZAC) and da Zone Fundida (ZF).
Abstract: Os acos inoxidaveis duplex (AID) apresentam em sua microestrutura ferrita e austenita, de modo a aliar boas propriedades mecânicas e resistencia a corrosao. Estes materiais possuem grande aplicacao na industria petroquimica, sendo o UNS S31803 um dos mais conhecidos. Existem poucos trabalhos referentes ao estudo da influencia da restricao na soldagem da junta na formacao de Widmanstatten. Logo, este trabalho tem como objetivo analisar a influencia da restricao no balanceamento de fases, na morfologia da austenita, na microdureza e na tenacidade da Zona Afetada pelo Calor (ZAC) e da Zona Fundida (ZF). Foram realizadas soldagens em juntas tipo V utilizando eletrodo revestido AWS E2209-17com dois niveis de energia: 15 kJ/cm e 20 kJ/cm, com e sem restricao. De maneira geral, houve maior quantidade de ferrita nos passes de acabamento em relacao aos passes de enchimento e de raiz. Foram observadas maiores quantidades de Widmanstatten nas condicoes soldadas com restricao. A ZAC apresentou uma microestrutura mais grosseira nos passes de acabamento. No entanto, nao foram observadas diferencas significativas nas microestruturas quando comparadas as condicoes com e sem restricao. As condicoes que apresentaram maior quantidade de Widmanstatten obtiveram menores niveis de microdureza. Nao foram observadas diferencas na energia absorvida na ZAC e ZF. Palavras-chave: Duplex; Restricao; Microestrutura; Microdureza; Tenacidade.
Cites background from "Effect of weld metal chemistry and ..."
...Além disso, outras razões podem estar relacionadas, como: tensões residuais, dureza, tamanho de grão e esferoidização de partículas de austenita intragranular, além de formação de fases fragilizantes [4]....
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...É primordial a obtenção do balanço microestrutural de 50% austenita e 50% ferrita para aliar boa resistência mecânica e resistência à corrosão [4]....
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10 Jan 2018
TL;DR: In this article, the shear strength of UNS S32750 super duplex stainless steel to AISI 304 austenitic stainless steel using BNi-2 interlayer was carried out at 1050 oC for 45 min.
Abstract: Transient liquid phase bonding of UNS S32750 super duplex stainless steel to AISI 304 austenitic stainless steel using BNi-2 interlayer was carried out at 1050 oC for 45 min. Microstructure analyses of the joint were carried out using optical microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Microhardness indentation and shear strength test were performed to assess mechanical behavior of the joint. No eutectic contents was seen at the joint and thus Isothermal solidification was completed at 45 min bonding time. The shear strength of the joint was about 0.7 of duplex stainless steel shear strength. Froctographic studies revealed that the fracture mode was completely ductile in the case of the joint made at bonding time of 45 min.
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01 Jan 1997
TL;DR: In this paper, the authors present a non-destructive testing of welds for service experience, based on the application of service experience in metallurgy and metallurgical applications.
Abstract: Developments, grades and specifications Alloy design Microstructure Forming and machining Physical and mechanical properties Corrosion Stress corrosion cracking Welding metallurgy Welding processes Weld properties Non-destructive testing of welds Applications Service experience.
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