MoおよびBを含む12%Cr耐熱鋼の長時間クリープ破断強度におよぼすVおよびNbの影響
1975 年 61 巻 11 号 p. 2604-2616
詳細
1975 年 61 巻 11 号 p. 2604-2616
The effects of vanadium and niobium were investigated in order to improve the creep rupture strength of 12% Cr heat resisting steel. The results obtained are as follows:
1) The creep rupture strength of 12% Cr heat resisting steel is increased by additions of vanadium and niobium. Additions of vanadium and niobium result in precipitation hardening.
2) The optimum amounts of vanadium and niobium depend on creep rupture test condition. When tested at 600°C for 100 hr 0.18% V and 0.15% Nb are the optimum amounts. When tested at 600°C for 10000 hr 0.24% V and 0.15% Nb are the optimum amounts. Thus, it seems that the longer the testing time, the higher is the optimum amount of vanadium.
3) It has been observed in an electron microscope that coalescence of precipitated carbide particles are retarded by additions of vanadium and niobium.
