The new Ni-Cr-Fe nickel base alloy ( % ： 0. 036 ~ 0. 044C

16. 71 ~ 17. 10 Cr

63. 04 ~ 63. 95Ni

8. 98 〜 10. 76Fe

2.50〜2.88Mo

2.01 ~4.97Nb

0. 06V

0. 74 ~0. 82Al

2.00〜2.06Ti) is melted by a 25kg vacuum induction furnace and forged to Φ15 mm and 14 mm x 14 mm bar products. The effect of niobium content on structure and mechanical properties of the 65Ni~18Cr-10Fe alloy has been studied by busing scanning electron microscope

X-ray diffractometer

chemical phase analysis and tensile tester. Results show that with increasing niobium content in alloy

the precipitated amount and dimension of γ′、γ″ and η phase increase

of which the morphology changes from discontinuous particles or short clubs to long lamellae led to increment of ambient tensile strength of alloy and decrease of plasticity.