The Paton Welding Journal, 2012, №07



2012 №07 (05)

2012 №07 (07)

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The Paton Welding Journal, 2012, #7, 23-27 pages  

EFFECT OF HEAT TREATMENT ON SENSITIVITY OF THE HAZ METAL ON TITANIUM-STABILISED AUSTENITIC STEEL TO LOCAL FRACTURE

Yu.V. POLETAEV

Volgodonsk Institute (Branch) of South Russian State Technical University
(Novocherkassk Polytechnic Institute), Volgodonsk, Russia
 
 
Abstract
The mechanism of embrittlement of the HAZ metal of welded joints on steel 12Kh18N12T was revealed. This mechanism was found to be associated with development of the processes of direct and relative softening of grain boundaries in welding and at high-temperature low-frequency low-cycle loading. The efficiency of austenising to improve local fracture resistance of the welded joint HAZ metal was experimentally proved.
 
 
Keywords: arc welding, welded joint, austenitic steel 12Kh18N12T, heat-affected zone, structural and chemical microheterogeneity, evaluation of weldability, optical and electron microscopy, heat treatment - austenising, low-frequency low-cycle loading, local fracture
 
 
Received:                29.11.11
Published:               28.07.12
 
 
References
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8. Poletaev, Yu.V. (2010) Long-term low-cycle strength of welded joints and choice of austenite-stable steels. Novocherkassk: LIK.
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10. Lyuttsau, V.G. (1977) Current concepts of a structural mechanism of deformation ageing and its role in fracture propagation at low-cycle fatigue. Ibid., 5-21.
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