Effect of Heat Treatment and Thermal Exposure on Microstructure of the Alloy C⁺ Bars

Abstract:

The microstructures of the Alloy C⁺ with three different heat treatment processes have been investigated after exposure at 550 °C for 100 hours in this study. The alloy shows typical equiaxed β grains with second phase precipitation and twin formation inside the β grains in the as-rolled condition. Solution treatment at lower temperature led to a smaller β grain size while higher temperature solution treatment produced coarse grains with increasing precipitated phases inside the β grains. Ageing treatment after solution and thermal exposure for a long period of time resulted in an increasing α phase precipitation at the grain boundaries due to their tendency for preferential nucleation of second phases. In a certain condition, continuous coarsening of the α phase is concentrated on the grain boundaries therefore violate the properties of the alloy.

• Periodical: Materials Science Forum (Volume 765)
• Pages: 506-510
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.765.506
• Online since: July 2013
• Authors: Xiao Xiang Wang, Wei Qi Wang, Yong Qiang Zhang
• Keywords: Aging, Alloy C⁺, Precipitation, Solution, Thermal Exposure

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