Fracture Toughness Variations in Alloy 718

[+] Author and Article Information
W. J. Mills, L. D. Blackburn

Hanford Engineering Development Laboratory, Westinghouse Hanford Company, Westinghouse Electric Corporation, Richland, Wash. 99352

J. Eng. Mater. Technol 110(3), 286-293 (Jul 01, 1988) (8 pages) doi:10.1115/1.3226050 History: Received August 10, 1987; Online September 15, 2009


Heat-to-heat and product-form variations in the JIc fracture toughness of Alloy 718 were examined at 24°C, 427°C, and 538°C using the multiple-specimen JR -curve method. Five different material heats along with three product forms from one of the heats were tested in the conventional heat-treatment condition. Statistical analysis revealed only two significantly different JIc levels of 48 kJ/m2 and 74 kJ/m2 for these materials. These two mean JIc levels were independent of temperature. A minimum-expected JIc level based on a tolerance interval bracketing 90 percent of the lower JIc population at a 95 percent confidence level was evaluated as 33 kJ/m2 . Coarse δ precipitates controlled the fracture properties by initiating secondary dimples that pre-empted continued growth of primary dimples nucleated by broken carbide inclusions.

Copyright © 1988 by ASME
Your Session has timed out. Please sign back in to continue.






Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In