Tensile deformation dominated by matrix dislocations at intermediate temperatures revealed using in-situ EBSD in superalloys

Figures & data

Figure 1. At intermediate temperatures, Ni-based single crystal superalloys do have similar microstructures under different deformation conditions: (a) The tensile curve of the experimental alloy at 750 °C and the orientation before and after fracture; (b) The microstructure of the experimental alloy after tensile at 750 °C; (c) The tensile creep curve of the experimental alloy at 750 °C/750 MPa and the orientation before and after creep fracture; (d) The microstructure of the experimental alloy after tensile creep at 750 °C/750 MPa.

Figure 2. (a) Schematic diagram of the tensile specimen for in-situ EBSD analysis; (b) The macroscopic feature and the relationship between tensile direction and EBSD coordinates; (c) The stress-strain curve of the specimen for in-situ EBSD analysis.

Figure 3. Surface morphology evolution of the specimen at different deformation stages in Figure 2(c), and (a)-(h) represent stages A-H, respectively.

Figure 4. Orientation evolution of the specimen at different deformation stages and corresponding Schmid factors for twelve {111} 〈110〉 slip systems.

Table 1. Orientation of the specimen at different deformation stages.

	Average all Euler angle
Stage	φ1	Φ	φ2	Orientation
A	249.33	11.81	28.22	[1.22, 9.74, −1.91]
B	236.23	13.56	41.14	[1.13, 9.74, −1.95]
C	250.68	11.55	26.64	[1.19, 9.75, −1.89]
D	255.42	10.68	23.13	[1.42, 9.73, −1.79]
E	245.23	10.14	36.92	[2.02, 9.66, −1.60]
F	250.33	11.65	32.13	[2.05, 9.60, −1.90]
G	245.02	12.83	37.94	[2.10, 9.57, −2.01]
H	244.08	14.57	39.83	[2.22, 9.48, −2.26]

Figure 5. (a) The standard [010] stereographic projection; (b) The orientation rotation path of several alloys during tensile deformation at intermediate temperatures; (c) The orientation rotation path of several alloys during tensile creep at intermediate temperatures and high stress; (d) Illustration of orientation rotation in a standard stereographic triangle under {111} 〈110〉 slip; (e) Illustration of orientation rotation in a standard stereographic triangle under {111} 〈112〉 slip.