Effect of filler addition on solidification behaviour and hot tensile properties of GTA-welded tube joints of Super 304H austenitic stainless steel

Kumar, M. S. Mohan; Balasubramanian, V.; Rao, A. Gourav

doi:10.1186/s40712-015-0051-x

Cited by 5 publications

(6 citation statements)

References 25 publications

(22 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Discussionsupporting

confidence: 91%

“…The results of the RT tensile test of the as-welded specimens are in accordance with results R p0.2 = 349.6 MPa ± 10.2 and R m = 614.6 ± 11.7 MPa presented in [2]. On the contrary, the rupture in [2] occurred in the base material, while in our case in the HAZ. The tensile test of the specimens with homogeneous welded joint regardless of solution annealing showed that after long-term aging (650 • C/7560 h) the yield strength decreased while the hardness value increased.…”

Section: Discussionsupporting

confidence: 91%

“…In the HAZ of the nonannealed weld, the highest values of hardness are found close to the fusion line with the coarse grains, whereas the annealed welds have the highest values of hardness at the border of HAZ and the base materials in the coarse grain areas. Depending on the used filler material, delta ferrite may form in the weld metal as in the case of welds in [2] and [7] did.…”

Section: Discussionmentioning

confidence: 99%

“…This leads to a change in the mechanical properties; however, it is not clear what impact will have the previous deformation on the long-term operation of boiler. In the case of welding, as reported in [2], if the correct filler material is not chosen, it can cause the formation of delta ferrite. It can be a suitable nucleation site for undesirable brittle phases after long term operation [3].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Structural Stability of the SUPER304H Steel Used in Energetics

2022

View full text Add to dashboard Cite

This paper describes the influence of technological treatments (i.e., bending or welding) on the structural stability of SUPER304H austenitic steel used in reheaters and superheaters in fossil fuel power plants. Although the worldwide trend is transitioning to green power sources, the lifetime of existing power plants has to be prolonged until the transition is complete. Experimental material was tested in as-received state (straight tubes), bends, and homogeneous weld joints. Part of the specimens was solution-annealed after the technological operation. Afterwards, all the samples were thermally aged in furnace (650, 675 and 700 °C) for 7560–20,000 h. For comparison, bent specimens were placed at experimental sites on an operating powerplant for 10,000+ h. The long-term aging causes the formation of Cr-based carbides on the grain boundaries along with the Fe-Cr sigma phase. Combination of elevated temperature and residual stress accelerates formation of the sigma phase. This can be prevented by solution-annealing after bending. Mechanical properties were evaluated by Vickers hardness and tensile tests. The microstructure was observed using light optical microscopy (LOM) and scanning electron microscopy (SEM) with the energy-dispersive X-ray detector (EDXS). Electron backscatter diffraction (EBSD) and X-ray powder diffraction (XRPD) were used to characterize the brittle phases.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionsupporting

confidence: 91%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Structural Stability of the SUPER304H Steel Used in Energetics

2022

View full text Add to dashboard Cite

show abstract

“…The current issue and full text archive of this journal is available on Emerald Insight at: https://www.emerald.com/insight/1573-6105.htm migration (Pandey et al, 2018a, b). The elemental segregation caused due to the variation also results in the induction of thermal stresses (Vinoth Kumar et al, 2015). Ferritic steels have lower thermal expansion coefficient than that of the austenitic steels which will increase the localized stress in the austenitic region (Laha et al, 2001).…”

mentioning

confidence: 99%

Predicting hot wire tungsten inert gas welding parameters for joining P91 and 304HCu steel using multi-optimization techniques

Sravan

Rajakumar

Rajagopalan³

et al. 2023

MMMS

View full text Add to dashboard Cite

PurposeDissimilar joining of austenitic stainless steels and ferritic steels is a challenging task and has a wide range of applications due to its excellent mechanical and thermal characteristics. They are joined mostly by using conventional modes. In the current investigation, the study and optimization of hot wire TIG welding parameters was carried out.Design/methodology/approachThese parameters will govern the desired characteristics of the joint. Solutions were found out through multi-response optimization by using response surface methodology and single response optimization using particle swarm optimization.FindingsOptimized input welding parameters that were achieved are electrode current 180 amps, wire feed rate 1870 mm/min and hot wire current 98 amps and the optimized UTS is 665.45 MPa. The results from PSO were compared with RSM and the optimized input welding parameters for the electrode current, hot wire current and wire feed rate exhibited maximum ultimate tensile strength which were also confirmed from response and contour plots.Originality/valueSensitivity analysis was also performed to understand the effect of each individual parameters on the response. Microstructure features were evaluated for the joints and was found that the characteristics are within the desired criteria.

show abstract