 At room temperature, ES-1's yield (tensile strength before deformation) is 224,500 PSI (1547 MPa), ultimate strength (breaking point) is 263,700 PSI (1818 MPa).At 900°C, yield is 193,900 PSI (1337 MPa), and ultimate strength is 246,700 (1701 MPa).Rockwell hardness is 45.6 (455 HV10).