Structure and mechanical properties of maraging steel 00Ni14Cr3Mo3Ti (% ： 0. 002C

14. 06Ni

3. 19Cr

3. 06Mo

1. 32Ti) with 750 ~ 1 050 °C solution treatment have been studied. Results showed that with ≤900 °C solution treatment the austenite grain size and strength of steel wasn't obvious change

as solution temperature was more than 900 °C

with increasing temperature the austenite grain size increased appreciably and the strength of steel presented declining trend. As solution temperature increased from 750 °C to 900 °C

with decreasing Fe

2

Mo phase amount in steel and completely dissolving at 810 °C

the impact energy of the steel increased from 32 J to 61 J

and as solution temperature increased from 900 °C to 1 050 °C

with austenite grain coarsening the impact energy decreased from 61 J to 26 J.