Study on the Undercoolability and Single Crystal Castability of Nickel-Based Superalloys

  • Haiwei Wang
  • Dexin Ma
  • Gongxian Yang
  • Xiufang Gong
  • Qiongyuan Zhang
  • Xianping Wei
Chapter
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

The critical undercooling degree (ΔTN) of nickel-based superalloys has a great relationship with the single crystal castability. This paper studied the ΔTN of DD483, CMSX-4 and CMSX-6, also analyzed the factors affecting ΔTN, including chemical composition, shell materials and remelting cycle. The results show that when experiment condition of pouring temperature and shell materials remains the same, three kinds of superalloys have different undercoolability, and the order of the critical nucleation undercooling degree from high to low is CMSX-6, CMSX-4, DD483. Because of the influence of wettability between alloy melt and shell, ΔTN of CMSX-4 in the pure Al2O3 shell is greater than which in EC95 shell (95% pure corundum + 5% quartz). With increasing the number of remelting, shell aging may pollute the alloy melt, leading to a decline in the undercoolability of the alloy.

Keywords

Nickel-based superalloys Directional solidification Undercoolability Stray grains 
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Copyright information

© The Minerals, Metals & Materials Society 2017

Authors and Affiliations

  • Haiwei Wang
    • 1
    • 2
  • Dexin Ma
    • 1
    • 2
  • Gongxian Yang
    • 1
    • 2
  • Xiufang Gong
    • 1
    • 2
  • Qiongyuan Zhang
    • 1
    • 2
  • Xianping Wei
    • 1
    • 2
  1. 1.State Key Laboratory of Long-Life High Temperature MaterialsDeyangChina
  2. 2.Materials Research CenterDongfang Turbine Co., Ltd.DeyangChina

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