Cr-based alloy having an excellent strength-ductility balance at high temperature
A strength-ductility balance at a high temperature above 1000° C., particularly a high temperature above 1050° C. is improved by rendering a chemical composition of Cr-based alloy into Cr: more than 60 mass % but less than 65 mass %, C+N: not more than 20 mass ppm, S: not more than 20 mass ppm, O: not more than 100 mass ppm, O as an oxide: not more than 50 mass ppm, and the remainder being Fe and inevitable impurities.
1. A Cr-based alloy having an excellent strength-ductility balance at temperatures not lower than 1000° C. and having strength-ductility balance of RA×TS≧10000 (%·MPa) at 1000° C. to 1200° C., consisting of Cr: more than 60 mass % but less than 65 mass %, C+N: present in a range of 0.1 mass ppm to 20 mass ppm, S: present in a range of 0.1 mass ppm to 20 mass ppm, O: present in a range of 5 mass ppm to 100 mass ppm, O as an oxide: present in a range of 3 mass ppm to 50 mass ppm, and the remainder being Fe and inevitable impurities.
2. The Cr-based alloy according to claim 1 wherein the O as an oxide is present in a range of 3 mass ppm to 30 mass ppm.
3. The Cr-based alloy according to claim 1 wherein the O is present in a range of 5 mass ppm to 50 mass ppm.
4. The Cr-based alloy according to claim 3 wherein the O as an oxide is present in a range of 3 mass ppm to 30 mass ppm.
5. The Cr-based alloy according to claim 1 wherein the S is present in a range of 0.1 mass ppm to 10 mass ppm.
6. The Cr-based alloy according to claim 5 wherein the O as an oxide is present in a range of 3 mass ppm to 30 mass ppm.
7. The Cr-based alloy according to claim 5 wherein the O is present in a range of 5 mass ppm to 50 mass ppm.
8. The Cr-based alloy according to claim 7 wherein the O as an oxide is present in a range of 3 mass ppm to 30 mass ppm.