Accession Number:

ADA080088

Title:

Deformation and Fracture of Advanced Anisotropic Superalloys.

Descriptive Note:

Final technical rept. 1 Oct 75-30 Sep 79,

Corporate Author:

PRATT AND WHITNEY AIRCRAFT GROUP EAST HARTFORD CONN

Personal Author(s):

Report Date:

1979-11-01

Pagination or Media Count:

67.0

Abstract:

The modern single crystal superalloy baseline of Ni-5A1-2Ti-1Nb-9Cr-12W by weight was selected PWA 1444. The ReW ratio was varied from 0.0 to 1.0 as the Re W was held constant at 12 wt . Single crystals were grown with axial orientations of 001, 110, and 111 from four different alloys and were fully heat treated gamma prime solution age. An additional alloy was made at 4Ta4W4Re in the three high symmetry orientations. Test specimens of the compressive and tensile creeprupture design were obtained by sectioning or electrochemical machining. Creep data were obtained in tension and compression with temperaturestress combinations of 816 C650 Mpa, 899 C380 MPa, 982 C220 MPa and 1066 C138 MPa 1500 F94 ksi, 1650 F55 ksi, 1800 F32 ksi and 1950 F20 ksi. Crystals were characterized by chemical analysis, optical metallography and crystallographic orientation determination by the Laue method. Aging studies were carried out at 816 C 1500 F, 899 C 1650 F, 982 C 1800 F and 1066 C 1950 F. The Re content was found to systematically and substantially refine the gamma prime particle size. Transmission electron microscopy was carried out after 0.20 creep strain at 899 C 1650 F. The primary slip system was consistently 111 110 for 001 and 110 oriented specimens but 100 110 slip was found for the 111 oriented tensile and compressive samples at 0 Re. Higher Re levels showed a lesser tendency for cube slip. The Re addition substantially strengthens all three orientation tested, particularly 111.

Subject Categories:

  • Physical Chemistry
  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE