1. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS Warsaw University of Technology, Faculty of Materials Science and Engineering, Wołoska 141, 02-507 Warsaw, Poland Krystyna Lublińska, Andrzej Szummer, Krzysztof Jan Szpila, Krzysztof Jan Kurzydłowski 8 th May, Lisse klublin@meil.pw.edu.pl

2. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS OUTLINE 1.Introduction 2.Research goals 3.Investigated materials and research techniques 4.Results 5.Conclusions 2/23

3. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS BASIC INFORMATION Warsaw Faculty of Materials Science and Engineering Warsaw University of Technology The Faculty is currently carrying out 23 joint research projects with 19 foreign partners, which include: Waterloo University, Canada Beijing Polytechnic University, China Institute of Physics of the Czech Academy of Sciences Universite Paris-Sud XI, France Ecole des Mines de St. Etienne, France Dortmund University, Germany Max Planck Institut fur Metallforshung in Stuttgart, Germany Hungarian Academy of Sciences, Hungary Moscow State University, Russia Institutes of Physics of the Slovakian Academy of Sciences Ulsan University, South Korea Universidad Complutense de Madrid, Spain Oxford University, UK Department of Engineering Materials, University of Sheffield, UK Cornell University, USA independent faculty since 1991 institute since 1920 3/23

4. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS structural steels hydrogen degradation (hydrogen corrosion) microstructural changes reduction of useful properties clad plates disbonding differences in: diffusion and solutibility of hydrogen temperature crystalographic structure R. Paschold, L. Karlsson, M. F. Gittos, „Disbonding of Austenitic Weld Overlays in Hydroprocessing Applications”, Svetsaren no. 1 – 2007, 10-15 4/23

5. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS FCC vs. BCC www-ee.ccny.cuny.edu austeniteferrite hydrogen diffusion coefficient10 -15 m 2 /s8,46·10 -11 m 2 /s hydrogen solutibilitylow high LOCAL SUPERSATURATION OF HYDROGEN DISBONDING 5/23

6. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS RESEARCH GOALS 1.Investigation of influence of cathodic hydrogen on microstructure of the interface of clad plate (304L/13CrMo4-5) 2.Determination of influence of heat treatment on hydrogen corrosion of the interface of clad plate (304L/13CrMo4-5) 6/23

7. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 15 mm of low alloy steel (13CrMo4-5) Claded plates were manufactured during intership at ZTM „EXPLOMET” in Opole, Poland Chemical composition [wt %] CSiMnSCrNiMo 304L0,0190,341,680,00118,278,11- 13CrMo4-50,150,250,590,0150,830,0930,49 INVESTIGATED MATERIALS 3 mm of austenitic stainless steel (304L) 304L 13CrMo4-5 7/23

8. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS light microscopy scanning electron microscopy shear tests (according to ASTM SA-264) ANNEALING RESEARCH TECHNIQUES 1223K (950°C) 1 hour argon atmosphere cooled with furnace 8/23

9. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS EXPERIMENTAL - HYDROGEN CHARGING Hydrogen charging parameters: 0,5M H 2 SO 4 solution, with 1mg/dm 3 As 2 O 3 addition (hydrogen entry promoter), ambient temperature, current density: 50mA/cm 2 time: 18 hours Hydrogen charging parameters: 0,5M H 2 SO 4 solution, with 1mg/dm 3 As 2 O 3 addition (hydrogen entry promoter), ambient temperature, current density: 50mA/cm 2 time: 18 hours specimen _ _ platinium anode + + H 2 SO 4 + As 2 O 3 power supply (i – const.) 304L 13CrMo4-5 9/23

10. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS polisched, unetched, uncharged sample 10/23

11. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS EFFECT OF HYDROGEN CHARGING hydrogen induced blisters in 13CrMo4-5 steel hydrogen induced blisters with microcracks in 13CrMo4-5 steel 11/23

12. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS a) 20h after hydrogen charging, 18 h, 0.1 A/cm 2 c) without hydrogen charging XRD patterns of 304 steel A. Szummer,”Hydrogen Degradation of Ferrous Alloys” USA (1985), 512 a) b) c) 304 b) directly after hydrogen charging, 18 h, 0.1 A/cm 2 EFFECT OF HYDROGEN CHARGING 12/23

13. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS EFFECT OF HYDROGEN CHARGING hydrogen induced microcracks (intergranular and transgranular) in 304L steel 13/23

14. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 304L 13CrMo4-5 304L 13CrMo4-5 EFFECT OF HYDROGEN CHARGING 304L 13CrMo4-5304L 13CrMo4-5 304L unannealed, hydrogen charged 14/23

15. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 6/xx EFFECT OF ANNEALING 304L 13CrMo4-5 304L 13CrMo4-5 unannealedannealed 15/23

16. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS EFFECT OF ANNEALING 304L13CrMo4-5 304L 13CrMo4-5 unannealedannealed 16/23

17. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 6/xx EFFECT OF ANNEALING 304L 13CrMo4-5 304L 13CrMo4-5 unannealedannealed 17/23

18. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS EFFECT OF ANNEALING 304L 13CrMo4-5 304L 13CrMo4-5 unannealedannealed 18/23

19. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 304L13CrMo4-5 304L 13CrMo4-5 EFFECT OF ANNEALING AND HYDROGEN CHARGING 13CrMo4-5 304L 13CrMo4-5 unannealedannealed 19/23

20. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS Shear strenght loss: Z = (R tN – R tH ) ∙ 100%/ R tN, where: R tN – shear strenght of uncharged sample, R tH – shear strenght of hydrogen charged sample. SHEAR TESTS RESULTS 20/23

21. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS 16/xx SHEAR TESTS RESULTS uncharged, unannealedhydrogen charged, unannealed hydrogen charged, annealeduncharged, annealed 21/23

22. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS CONCLUSIONS Hydrogen causes significant changes in microstructure in the flyer layer (surface microcracks and blisters) and base layer (blisters) of the investigated clad plates. Annealing, which removes the high deformation of grains, allows to fabricate a clad plate, which may work in enviroment with hydrogen presence. Strong detoriation of microstructure, caused by explosion cladding, increases susceptibility to increased hydrogen embritllement in the thin layer of austenitic stainless steels along the interface. Annealing allows to avoid formation of brittle area along the interface, produce more homogeneous material and reduces the negative effect of hydrogen. 22/23

23. HYDROGEN DEGRADATION OF EXPLOSION CLADDED STEELS THANK YOU FOR YOUR ATTENTION 23/23