Welding high-strength thick stainless steels after strengthening by heat treatment

• Published in: Welding international 2002-01, Vol.16 (4), p.307-311
• Main Authors: Laz'ko, V E, Lukin, V I, Maksimovich, T L
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Joining, thermal cutting: metallurgical aspects; Metals. Metallurgy; Welding
• ISSN: 0950-7116; 1754-2138
• DOI: 10.1080/09507110209549535

The aim of the work was to optimise the chemical composition of the material of the transition piece and welding technology, with special reference to high-strength stainless steels. The investigations were carried out on maraging 03Kh11N11M2TF-VD (EK8-VD, VNS36-VD) and martensitic 18Kk14N4AM3 steels with a thickness of 12-30 mm, with different types of hardening. The 18Kh14N4AM3 steel was quenched from 1100 deg C in oil, held at -70 deg C for 3 hrs and tempered at 200 deg C for 1-3 hrs to obtain sigma sub fi = 1570-1765 MPa, and 03Kh11N11M2TF-VD steel was subjected to quenching from 860 deg C, holding at -70 deg C for 3 hrs, and ageing at 525 deg C for 1 hr to obtain sigma sub B = 1420-1620 MPa. Both steels after strengthening by heat treatment had a martensitic structure with 10-25% of retained austenite. The material of the transition piece was creep-resisting steels 07Kh12N2MVF (EP609), 07Kh14K3N2MVFB (EK-83), 11Kh11N2V2MF (EI962) and 13Kh16N3M2GAF (VNS57) and also stainless steels 06Kh14N6D2MBT (EP817) and 03Kh12N10MT with a higher carbon content. In welding the transition piece and in welding through a transition piece, the experiments were carried out with manual arc argon-shielded TIG welding with filler wire (Sv-07Kh12N2VMF, Sv-08Kh14N7-KVM-VI, Sv-06Kh13N6M4K8B, Sv-03Kh12N9M2S-VI), and welding with coated electrodes OZL-46 and electron beam welding (EBW).