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 article, super duplex stainless steels (SDSS) are used in high technology applications in construction, chemical and shipbuilding industries and they undergoes micropolymerization.
Abstract: Owing to their excellent properties, super duplex stainless steels (SDSS) are used in high technology applications in construction, chemical and shipbuilding industries. However, SDSS undergoes mic...
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01 Jan 2019
TL;DR: In this paper, the influence of cooling rates on the ferrite content of duplex stainless steels was investigated and it was found that cooling rate can influence the overall ferrite/austenite ratio and achieving the proper balance of phases is crucial in producing a casting with suitable mechanical and corrosion properties.
Abstract: Highly alloyed CD3MWCuN was chosen to investigate the influence of cooling rates on the ferrite content of duplex stainless steels. It is known that cooling rate can influence the overall ferrite/austenite ratio, and achieving the proper balance of phases is crucial in producing a casting with suitable mechanical and corrosion properties. Initial experiments were carried out to study the ferrite/austenite ratio as a function of cooling involved samples obtained using different cooling rates through the solidification temperature as well as different cooling rates from the homogenization temperature. A single keel bar was obtained, sectioned, and recast at six different solidification cooling rates. Each of the six castings was then sectioned into six pieces and each piece cooled from the homogenization temperature to produce six different homogenization cooling rates. Backscattered electron imaging was used to measure the phase percentages and observe the microstructures. The ferrite content was found to increase with increasing homogenization cooling rates. It was also found that the homogenization cooling rate should be higher than 200 °C/h in order to get high ferrite contents (> 40%). As the cooling rate slows, intermetallic phases such as sigma start to precipitate at the grain boundaries.
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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.
449 citations