Recrystallization of Ni3Al Base Single Crystal Alloy IC6SX with Different Surface Mechanical Processes

The recrystallization behavior of Ni3Al base single crystal alloy IC6SX with different mechanical processes has been studied. The specimens of the alloy were treated by surface cleaning and cold working during the blades manufacture, and then heat treated in the temperature range of 800–1260°C for 1 h to 4 h. The microstrcture of the specimens were examined by optical and scaning electron microscopy, and the room temperature tensile property, stress rupture property under the test condition of 1100°C/130 MPa, and the thermal cycle fatigue resistance under 1100–20°C of the specimens with and without recrystallization were carried out. The experimental results showed that the initial recrystallization nucleation temperatures of the alloy by dry grit blasting, wet grit blasting, indentation, shot blasting and burnishing were 900–950°C/1 h, 1000–1100°C/1 h, 1200–1220°C/4 h, 1220–1240°C/1 h and 1220–1240°C/1 h, respectively and the primal recrystallization completing temperatures of the alloy by those mechanical processes mentioned above were 1200–1210°C/1 h, 1100–1200°C/1 h, 1220–1240°C/4 h, 1240–1260°C/1 h and 1240–1260°C/1 h, respectively. The results also indicated that the deformation amount of the specimens by burnishing and dry grit blasting was bigger than that by wet grit blasting and shot blasting according to their recrystallization temperature and the micro-hardness profile below the surface of specimens. It has been found that the recrystallization had no evident effect on mechanical properties of the alloy.