| 摘要 |
PURPOSE:To improve the creep strength of a high Cr ferritic steel and the characteristics at high temp. without carrying out normalizing by successively subjecting the steel contg. specified amts. of Nb and V to holding at a specified temp., final hot working, quenching and tempering. CONSTITUTION:A precipitation strengthening high Cr ferritic steel contg., by weight, 0.03-0.3% C, <=0.1% N, 5-13% Cr and 0.01-0.1%, in total, of V and/or Nb is cast. The cast steel is hot rolled and the resulting stock is heated, held at 930-1,300 deg.C for >=1 min and finally hot worked. The stock is then quenched to form a martensite structure and it is tempered at the Ac1 point or below or warm worked after heating to the Ac1 point or below. Stress relief annealing at the Ac1 point or below may further be carried out as required. |
