Examples and Discussions 1.F-N 900 800 (y-Fe) (b) 700 680±5℃ 2.8t650℃ 密 Cy a-Fe) 4.55 喱600 590℃ 500 150 5.7% 6.1% 400 Fe 1 6 8C0910 %Examples and Discussions 1. F-N