Grain Orientation Optimization of Two-Dimensional Grain Selector during Directional Solidification of Ni-Based Superalloys

Materials, vol. 13, pp. 1121

Abstract

The grain selection method is widely used in industry to produce Ni-based single crystal superalloys. A Z-form two-dimensional (2D) grain selector was designed to obtain high-quality single crystals. To control grain orientation deviation, one of the most important defects of the single crystal superalloys in casting, Z-form 2D grain selectors with different take-off angle were investigated in this study. The MM247LC superalloy single crystal samples were obtained by the Bridgman method modified by the Z-form grain selectors in this study. The Electron Backscattered Diffraction (EBSD) and the Optical Microscopy (OM) were used to observe and measure the grain selection growth and the microstructural evolution and orientation of the single crystal were also discussed. The results show that a Z-form 2D grain selector with an appropriate take-off angle can significantly reduce the deviation of the grain orientation. A single crystal superalloy with a deviation angle less than 6° can be obtained effectively when the take-off angle was 40°.

Authors 4

1. Xintao Zhu Aachen Foundry Institute

   State Key Laboratory of Mechanical Manufacturing System Engineering · Xi'an Jiaotong University · RWTH Aachen University

   Affiliation as printed

   Foundry Institute, RWTH Aachen University, Intzestrasse 5, 52072 Aachen, Germany

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, Shanxi, China

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, Shanxi, China

2. Qiang Yang

   State Key Laboratory of Mechanical Manufacturing System Engineering · Xi'an Jiaotong University

   Affiliation as printed

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, Shanxi, China

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, Shanxi, China

3. Fu Wang corresponding Aachen Foundry Institute

   State Key Laboratory of Mechanical Manufacturing System Engineering · Xi'an Jiaotong University · RWTH Aachen University

   Affiliation as printed

   Foundry Institute, RWTH Aachen University, Intzestrasse 5, 52072 Aachen, Germany

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, Shanxi, China

   State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, Shanxi, China

4. Dexin Ma Aachen Foundry Institute

   RWTH Aachen University

   Affiliation as printed

   Foundry Institute, RWTH Aachen University, Intzestrasse 5, 52072 Aachen, Germany