STAINLESS STEEL 660
660 is a Fe-25Ni-15Cr type high-temperature alloy. It exhibits high yield strength and endurance and creep strength below 650℃, and also possesses good processing ductility and satisfactory welding performance.
| Class A | Solution treatment, at 900 ± 14°C for at least 2 hours, followed by liquid quenching; Hardening treatment , at 720 ± 14°C for at least 16 hours, then air-cooled. | ||||
| Class B | Solution treatment , at 980 ± 14°C for at least 1 hour, then liquid quenched; Hardening treatment, at 720 ± 14°C for at least 16 hours, then air-cooled | ||||
| Class C | Solution treatment, at 980 ± 14°C for at least 1 hour, then oil quenched; Hardening treatment, at 775 ± 14°C for at least 16 hours, then air-cooled, followed by holding at 650 ± 14 °C for at least 16 hours, then air-cooled | ||||
| Class D | Solution treatment, at 900 ± 14°C for at least 2 hours, liquid quenched or at 980 ± 14°C for at least 1 hour, then liquid quenched; Hardening treatment, at 720 ± 14°C for at least 16 hours, air-cooled. If performance is required, secondary aging is performed at 650 ± 14 °C for at least 16 hours, then air-cooled | ||||
660 Austenitic Stainless Steel Chemical Composition