Patent ID: 9738954
Date: 2017-08-22
CPC Classifications: B22D,C22C,F01D

Claim:
1. A turbine wheel of an automotive turbocharger, comprising a Ni-based alloy having a composition which contains, in terms of mass %: C: 0.08 to 0.20%; Mn: 0.25% or less; Si: 0.01 to 0.50%; Cr: 12.0 to 14.0%; Mo: 3.80 to 5.20%; Nb+Ta: 1.80 to 2.80%; Ti: 0.50 to 1.00%; Al: 5.50 to 6.50%; B: 0.005 to 0.015%; Zr: 0.05 to 0.15%; and Fe: 0.01 to 2.5%, with the remainder being Ni and unavoidable impurities, wherein the turbine wheel comprises a wing part and a shaft part, and a size of γ′ phase in each site of from a tip of the wing part to the shaft part is structure-controlled so as to fall within a range of from 0.4 to 0.8 μm.