Fig. 1. Laser solid formed DZ125 superalloy sample. (a) Top view; (b) front view

Fig. 2. Mirco-morphologies of as-deposited and 2 h solution-treated γ' phases at different solution temperatures.(a) 1160 ℃; (b) 1180 ℃; (c) 1200 ℃; (d) 1220 ℃; (e) 1240 ℃; (f) as-deposited

Fig. 3. Morphologies of as-deposited and different heat-treated γ' phases of laser solid-formed samples. (a) As-deposited; (b) 1180 ℃/2 h/AC; (c) 1180 ℃/2 h/AC+850 ℃/12 h/AC; (d) 1180 ℃/2 h/AC+1000 ℃/12 h/AC

Fig. 4. Carbides obtained after heat treatment at 1180 ℃/2 h/AC+1000 ℃/12 h/AC. (a) M6C or M23C6;(b) MC(2); (c) energy spectrum for Fig.4(a); (d) energy spectrum for Fig.4 (b)

Fig. 5. Mirco-morphologies of γ' phases heat-treated at 1240 ℃/2 h/AC+1100 ℃/2-8 h/AC. (a) 2 h; (b) 3 h; (c) 4 h; (d) 5 h; (e) 6 h; (f) 8 h

Fig. 6. Mirco-morphologies of γ' phases heat-treated at 1240 ℃/2 h/AC+870 ℃/8, 16, 20 h/AC. (a) 8 h; (b) 16 h; (c) 20 h

Fig. 7. Size and volume fraction of γ' phase versus aging time. (a) Aged at 1100 ℃; (b) aged at 870 ℃

Fig. 8. Statistical results of size of γ' phases at 1100 ℃ for different aging time. (a) 2 h; (b) 3 h; (c) 4 h; (d) 5 h

Fig. 9. Dissolution of small size γ' phases at 870 ℃ for different aging time. (a) 16 h; (b) 20 h

Fig. 10. Relationship between γ' phase size and aging time under different aging temperature

Fig. 11. Probability function of γ' particle size. (a) Statistical value and calculated value at 1100 ℃ for 2 h aging time; (b) statistical value at 1100 ℃ for 2-5 h aging time

Fig. 12. Fitting result of ln (kLSWT) versus 1/T in aging process