Effect of phase proportion and solution temperature on structure and mechanical properties of steel 00Cr25Ni7Mo4N ( % ： 0. 007 ~0.009C

24. 50 〜24. 84Cr

6.92 〜6.99Ni

3.65 〜3. 72Mo

0. 27 ~0. 30N) melted by vacuum induction furnace (6. 5 kg ingot) has been studied. Results showed that with increasing solution temperature from 1 050 °C to 1 200 °C

ferrite content in steel increased from 48% 〜50% to 53% 〜55% ; with increasing solution temperature from 1 050 °C to 1 100 °C

the strength of steel decreased while the elongation and impact toughness of steel increased

and with increasing the solution temperature from 1 100 °C to 1 200 °C

the strength of steel increased while the e- longation and impact toughness of steel decreased

so optimum temperature of the steel was 1 100 °C ±50°C.