Low thermal expansion Ni-base superalloy

A low thermal expansion Ni-base superalloy comprising, by weight % (hereinafter the same as long as not particularly defined),

• C:
• 0.15% or less;
• Si:
• 1% or less;
• Mn:
• 1% or less;
• Cr:
• 5 to 20%;
• at least one of Mo, W and Re of Mo+½ (W+Re) of 17 (exclusive) to 25%;
• Al:
• 0.2 to 2%;
• Ti:
• 0.5 to 4.5%;
• Fe of 10% or less;
• at least one of B:
• 0.02% and Zr:
• 0.2% or less;
• a remainder of Ni and inevitable impurities;
• wherein the atomic % of Al+Ti is 2.5 to 7.0;
• wherein the low thermal expansion Ni base superalloy contains both γ′ phase precipitate consisting of intermetallic compound Ni3Al, Ni3(Al, Ti) or Ni3(Al, Ti, Nb, Ta) and A2B phase precipitate consisting of intermetallic compound Ni2(Mo, Cr).