Effect of Low-Angle Boundary on Microstructure and Stress Rupture Property of a Third Generation Single Crystal Superalloy DD10

Abstract:

The microstructure of a third generation single crystal superalloy DD10 with 0°~15° grain boundary and stress rupture property at 980°C/280MPa and 1100°C/140MPa have been studied and compared in the present investigation. The results showed that the primary dendritic stems at either side of low angle boundary indicated angular differences as compared with structure of principal [001] crystal. After thermal treatment, the grain boundary changed from irregular chain structure of γ’ and γ to flat and thin γ layer. Under the condition of 980°C/280MPaand 1100°C/140MPa, stress rupture life of the DD10 alloy with 7° low angle boundary decreased little compared with [001] crystal. The rupture was non-intergranular fracture. The 9° low angle boundary did not have a remarkable effect on stress rupture property of the DD10 alloy.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 498-504
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.498
• Online since: June 2017
• Authors: Hui Fen Li, Li Jun Liu, Ming Xue, La Mei Cao
• Keywords: Low Angle Boundary, Microstructure, Stress Rupture Property, Third Generation Single Crystal Superalloy

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