Fig. 1. Directional spectral emissivity measuring equipment

Fig. 2. Effect of wavelength on the spectral emissivity of Ti-6Al-4V alloy at different temperatures and detection angles. (a) 573 K; (b) 623 K; (c) 673 K; (d) 723 K; (e) 773 K; (f) 823 K

Fig. 3. Effect of detection angle on spectral emissivity of Ti-6Al-4V alloy at different temperatures. (a) 573 K; (b) 623 K; (c) 673 K; (d) 723 K; (e) 773 K; (f) 823 K

Fig. 4. Effect of temperature on spectral emissivity of Ti-6Al-4V alloy under different angles. (a) 0°; (b) 50°; (c) 60°; (d) 70°; (e) 80°; (f) 84°

Fig. 5. Effect of oxidation time on the spectral emissivity of Ti-6Al-4V alloy at different detection angles. (a) 0°; (b) 50°; (c) 60°; (d) 70°

Fig. 6. Effect of different oxidation time on the spectral emissivity of Ti-6Al-4V alloy at 20.0 μm. (a) 0--80 min; (b) 180--600 min