Investigation of Microstructural and Mechanical Properties of Dissimilar Metal Weld Between AISI 420 and AISI 1018 STEELS

The safe-end of a steam generator (SG) nozzle dissimilar metal weld (DMW) for pressurized water reactors (PWRs) is the weakest point of failure which is crucial for the safe operation of a nuclear power station. Related to materials micro-structures, a uniaxial stress–strain relationship is the basic input parameter for nuclear power plant design, safety evaluation, and life management. In this paper, the micro-structure and tensile mechanical properties of a DMW of a European pressurized water reactor (EPR) were studied. Vickers hardness tester, optical microscope, and electron back scatter diffraction were used to analyze the micro-structure of the DMW joint. In addition, the residual strain of the DMW joint base material, heat-affected zone, weld metal, and fusion boundary region were studied. Based on digital image correlation (DIC) technology, tensile mechanical properties of the DMW joint were obtained. The results show that an accurate tensile stress–strain relationship of dissimilar metal welded joints can be obtained by using the DIC technique, the weld is the relatively weak link, and the residual strain is concentrated in the heat-affected zone. This study provides valuable engineering information regarding nuclear power plant design, in-service performance testing, and structural analysis and evaluation of welds containing defects.

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Microstructure, local mechanical properties and stress corrosion cracking susceptibility of an SA508-52M-316LN safe-end dissimilar metal weld joint by GTAW

Materials Science and Engineering A ◽

10.1016/j.msea.2016.05.101 ◽

2016 ◽

Vol 669 ◽

pp. 279-290 ◽

Cited By ~ 37

Author(s):

Hongliang Ming ◽

Ruolin Zhu ◽

Zhiming Zhang ◽

Jianqiu Wang ◽

En.-Hou. Han ◽

...

Keyword(s):

Mechanical Properties ◽

Stress Corrosion ◽

Stress Corrosion Cracking ◽

Weld Joint ◽

Corrosion Cracking ◽

Dissimilar Metal ◽

Dissimilar Metal Weld ◽

Metal Weld

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Effect of buffer-layered buttering on microstructure and mechanical properties of dissimilar metal weld joints for nuclear plant application

Materials Science and Engineering A ◽

10.1016/j.msea.2016.04.053 ◽

2016 ◽

Vol 666 ◽

pp. 100-113 ◽

Cited By ~ 24

Author(s):

Dinesh W. Rathod ◽

P.K. Singh ◽

Sunil Pandey ◽

S. Aravindan

Keyword(s):

Mechanical Properties ◽

Nuclear Plant ◽

Dissimilar Metal ◽

Weld Joints ◽

Microstructure And Mechanical Properties ◽

Dissimilar Metal Weld ◽

Metal Weld

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Microstructures and Mechanical Properties of Dissimilar Metal Weld A508/52M/316L Used in Nuclear Power Plants

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.479.40 ◽

2011 ◽

Vol 479 ◽

pp. 40-47 ◽

Cited By ~ 3

Author(s):

Ke Wei Fang ◽

Guan Jun Li ◽

Guang Fu Li ◽

Wu Yang ◽

Mao Long Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Weld Metal ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Dissimilar Metal ◽

Primary Water ◽

Dissimilar Metal Weld ◽

Microstructures And Mechanical Properties ◽

Metal Weld

The microstructures and mechanical properties of a dissimilar metal weld A508/52M/316L used in the primary water system of pressurized water reactor (PWR) nuclear power plants were investigated. The weld exhibits complicated microstructures, with significant change around the interfaces A508/52M and 52M/316L. The variations of main elements in 52M weld metal are greater than those in the A508 and 316L, with significant changes in the zones closed to the interfaces. The bulk 52M weld metal has higher and more uneven hardness than both of the base metals A508 and 316L. The HAZ of A508 exhibits the highest hardness value in the weld. The area around the A508/52M interface is the most weak part for stress corrosion cracking (SCC) resistance of the weld in simulated PWR primary water at 290°C. SCC was only found in the specimens tested at +200mV(SHE) but not in those tested at both -780mV and Ecorr (about -500mV).

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Efecto del mantequillado en las propiedades mecánicas de uniones soldadas disímiles en barras de refuerzo para estructuras de concreto.

Revista ALCONPAT ◽

10.21041/ra.v6i3.151 ◽

2016 ◽

Vol 6 (3) ◽

pp. 248-261

Author(s):

J. C. I. Ramírez-Soto ◽

J. M. Salgado-López ◽

J. T. Pérez-Quiroz ◽

T. Pérez-López ◽

J. Terán-Guillén ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructural Analysis ◽

Concrete Structures ◽

Tensile Tests ◽

Plain Carbon Steel ◽

Dissimilar Metal ◽

Weld Joints ◽

Steel Bars ◽

Dissimilar Metal Weld ◽

Metal Weld

Efecto del mantequillado en las propiedades mecánicas de uniones soldadas disímiles en barras de refuerzo para estructuras de concreto RESUMENEn este trabajo se ha investigado la influencia de utilizar Inconel 182 como material de “mantequillado” en las propiedades mecánicas de uniones disimiles acero al carbono-inoxidable manufacturadas por soldadura con electrodo recubierto. Para ello se han empleado las siguientes técnicas: análisis microestructural, ensayos de microdureza Vickers y ensayos mecánicos de tensión. Se ha empleado el proceso de soldadura con electrodo recubierto por que es el más común en la soldadura de campo para la construcción. Los resultados demuestran que aun cuando las uniones disimiles sin “mantequillado” presentan defectos, sus propiedades mecánicas son superiores a las de las uniones soldadas con “mantequillado”. Esta metodología es propuesta para la rehabilitación de estructuras de concreto para ambiente marino con barras de acero como refuerzos.Palabras clave: mantequillado; uniones soldadas con materiales disimiles; propiedades mecánicas; microestructura; defectos. Effect of buttering in mechanical properties of dissimilar metal weld joints for reinforcement bars in concrete structures ABSTRACTIn this work, the influence of Inconel 182 as buttering material in the mechanical properties of dissimilar metal welds between plain carbon steel and stainless steel bars welded using SMAW has been investigated using microstructural analysis, Vickers microhardness testing, and tensile tests. Welding with SMAW process is commonly applied in field welding of concrete structures; therefore this process was selected for this work. The results indicated that even if the joints contain defects generated by the welder, the mechanical properties of dissimilar welded joint without buttering are higher than the properties of joints with buttering. This methodology is proposed for the rehabilitation of concrete structures with steel bars as reinforcements, which are located in marine enviroments. Keywords: buttering, dissimilar metal weld joints; mechanical properties; microstructure; defects. Efeito da introdução de um terceiro material sobre as propriedades mecânicas das juntas soldadas entre aço carbono e aço inox, em barras de aço para estruturas de concreto RESUMOEste artigo investiga a influência da utilização de Inconel 182 como um terceiro material, nas propriedades mecânicas de diferentes aços inoxidáveis soldados a aços carbono com uso de eletrodo revestido. Para tanto foram usados os seguintes métodos: análise microestrutural, ensaios de microdureza Vickers e ensaios mecânicos de tensão. Tem sido empregado o processo de solda com eletrodo revestido, porque é o mais comum no campo de solda para a construção. Os resultados mostram que quando as uniões são realizadas sem esse terceiro material, as propriedades mecânicas são superiores às das juntas soldadas com auxílio do Inconel 182. Esta metodologia, ora criticada, tem sido proposta para a reabilitação de estruturas de concreto em ambiente marinho, com uso de barras de aço inox como reforços.Palavras-chave: juntas soldadas com materiais diferentes; propriedades mecânicas; microestrutura; defeitos.

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