Volume 12 - Fractography Part 12 docx

[...]... shows dimples, together with quasi-cleavage facets that contain characteristic steps, river patterns, and tear ridges Fig 819, 821, and 822: TEM p-c replicas, all at 2000× Fig 820: TEM p-c replica, 5000× Failure due to sulfidation of a coupling for a hot-gas sampling line used in a coal-gasification pilot plant The coupling was made of the iron-nickel-base superalloy RA-330 (UNS N08330), joined using... single-crystal PWA 1480 with NiCoCrAlY applied by the low-pressure plasma spray process Fig 857: Fracture surface of coated sample tested at 1050 °C (1920 °F) in isothermal low-cycle fatigue The NiCoCrAlY coating was very ductile at the test temperature and did not crack The well-protected superalloy failed via multiple internal cracking originating at microporosity (arrow) SEM, 12. 5× Fig 858: High-magnification... element in grain boundaries 130× (D.R Diercks, Argonne National Laboratory) Hydrogen-embrittlement fracture of a single-cyrstal nickel-base superalloy (CMSX-2) developed for gas turbine engine applications Composition: 4.6% Co, 8.0% Cr, 0.6% Mo, 7.9% W, 5.6% Al, 0.9% Ti, 5.8% Ta, . sulfidation of a coupling for a hot-gas sampling line used in a coal-gasification pilot plant. The coupling was made of the iron-nickel-base superalloy RA-330 (UNS N08330), joined using Inconel. class="bi x5 yd w8 hd" alt="" Figure 817 shows a slow-bend fracture of a weld specimen made by gas tungsten-arc butt welding two 19-mm ( -in.) thick plates of 18% Ni maraging steel having a. 130× (D.R. Diercks, Argonne National Laboratory) Hydrogen-embrittlement fracture of a single-cyrstal nickel-base superalloy (CMSX-2) developed for gas turbine engine applications. Composition: