Two-phase alloy, product using said two-phase alloy, and method for producing said product

A two-phase alloy comprising Cr as a major component and comprising two phases of a ferrite phase and an austenite phase in a mixed state,

• wherein the two-phase alloy has a chemical composition comprising:
• 34% by mass or more and 70% by mass or less of Cr;
• 17% by mass or more and 45% by mass or less of Ni;
• 10% by mass or more and 35% by mass or less of Fe;
• 0.1% by mass or more and 2% by mass or less of Mn;
• 0.1% by mass or more and 1% by mass or less of Si;
• and
• impurities, wherein the impurities comprises:
• more than 0% by mass and 0.03% by mass or less of C;
• more than 0% by mass and 0.02% by mass or less of N;
• more than 0% by mass and 0.03% by mass or less of O;
• and
• wherein the chemical composition further comprises at least one of V, Ta and Ti as the constitutional component(s) of the two-phase alloy, the total content of the V, Ta and Ti being in the range of 0.8 times or more and 2 times or less of the total content of the C, N and O, and
• the total content of the Ni and the Fe is 30% by mass or more and 65% by mass or less.