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Tensile test (a) All weld metal in longitudinal direction (b) dimension of tested samples. 

Tensile test (a) All weld metal in longitudinal direction (b) dimension of tested samples. 

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Article
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AISI Type 304L austenitic stainless steels are extensively used in industries, and welding is an indispensable tool used for joining these materials. In a multi-pass weld, the development of residual stress to a large extent depends on the response of the weld metal, heat affected zone and parent material to complex thermo-mechanical cycles during...

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Context 1
... all weld metal tensile testing samples were machined from the welded plates in accordance to ASTM E8/E8M-08 standards. The tensile tests were designed to ensure that, the samples to be tested are taken as close as possible near the cap pass in longitudinal direction (welding direction of the plate) as shown in Fig. 6(a). As shown in the sketch ( Fig. 6(a)), 2/3 of the cap pass and 1/3 of fill 1 form the tested ...
Context 2
... all weld metal tensile testing samples were machined from the welded plates in accordance to ASTM E8/E8M-08 standards. The tensile tests were designed to ensure that, the samples to be tested are taken as close as possible near the cap pass in longitudinal direction (welding direction of the plate) as shown in Fig. 6(a). As shown in the sketch ( Fig. 6(a)), 2/3 of the cap pass and 1/3 of fill 1 form the tested ...
Context 3
... show in Fig. 16, during welding and subsequent cooling of material, residual stresses are generated in weldments due to dif- ferential heating and cooling rates [1,30]. When this material is cooling after welding, the stresses generated may exceed the yield strength, causing plastic deformation and work hardening in the weld metal. Since the root ...

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Citations

... Although its simplicity of execution, usually involving the deposition of molten filler metal and the localized heat input, the weld region close to the welded joint experiences complex thermo-mechanical cycles due to localized heating and cooling steps. Generally, these result in non-uniform expansion (heating phase) and shrinking (cooling phase) sequence of the region between the base metal and the welded material leading to distortion [1][2][3][4] particularly detrimental for the functional performance and service safety of the component. For this reason, an accurate knowledge of the thermomechanical aspects featuring the joining procedure and its evolution during the process execution is required with the aim to identify, control and minimize problems to achieve the desired and reliable outputs. ...
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... The early research on such a RS mitigation method was conducted in Russia by Kurkin et al. [19]. Post-weld rolling was found effective to reduce RS even in thick weld joints [20] and the effectiveness is proportional to the rolling load [18]. In the last decade high pressure rolling has been also widely implemented for controlling RS and distortion in WAAM. ...
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... Rather, the enhanced strength of the weld metal is attributed to the strain hardening induced by the complex thermo-mechanical loading caused by an uneven temperature distribution during the welding process [44,45,[49][50][51][52][53]. The deposited weld material is repeatedly subjected to heating followed by cooling (multi-pass weldment), whilst being mechanically constrained by the cooler parent metal. ...
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... They found that the welding tensile residual stresses in the Ti-6Al-4V welded parts can reduce from 550 to 50 MPa by a 2-h postweld heat treatment at 650°C. Recently, Sule et al. [18] have introduced the post-weld rolling method as a novel technique to refine tensile welding residual stresses. They showed that applying the post-weld rolling can not only reduce the welding tensile residual stresses in the weld center but also can induce compressive stresses. ...
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... Rather, the enhanced strength of the weld metal is attributed to the strain hardening induced by the complex thermo-mechanical loading caused by an uneven temperature distribution during the welding process [44,45,[49][50][51][52][53]. The deposited weld material is repeatedly subjected to heating followed by cooling (multi-pass weldment), whilst being mechanically constrained by the cooler parent metal. ...
... This increase in FWHM near the top is mainly due to plastic deformation [69], which is supported by the hardness plot of the IR specimen in Fig. 6 (b), showing work hardening to the same depth. This is approximately the depth of the layer height (~2 mm) plus the dilution depth (~2 mm) of the previous layer combined ( Table 1). ...
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... It is possibly that the higher heat input retards the rapid cooling rate and gives more time for ferrite to exist and solidify as a primary phase [29]. The FA microstructure was free of solidification cracking, this could be related to high crack resistance of the dual phase microstructure [15,30]. ...
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... Kim et al. [6] investigated the repairing-layer of nuclear power plant, and indicated that high stress in weld metal increases the sensitivity to SCC. The thermal cycles in multi-layers and multipasses could severely change the material properties [7,8], such as microstructure, element segregation, precipitation of grain boundary carbides, thus affected the stress corrosion behaviour in the weld metal. In this work, the stress corrosion cracking tests on the welded joint of low alloy high strength steel were conducted in a chloride solution at high temperature with O 2 . ...
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