Tohoku Steel boasts the largest domestic share of the engine valve heat-resistant steel market, and producing very reliable, high-quality, heat-resistant steel.
Heat-resistant steel for intake valves
Steel name and composition summary
| Steel Name | C | Si | Cr | Mo |
|---|---|---|---|---|
| SUH1 | 0.45 | 3 | 8 | ― |
| SUH3 | 0.40 | 2 | 11 | 1 |
| SUH11 | 0.50 | 1.5 | 8 | ― |
〔mass%〕
Physical property
Heat treatment temperature condition
High temperature mechanical properties
Heat treatment of test specimen
SUH1:1030℃,OQ／750℃,AC，SUH3:1050℃,OQ／750℃,AC
SUH11:1030℃,OQ／750℃,AC
Tempering temperature and normal temperature hardness
Heat-resistant steel for exhaust valves (iron-base)
Composition summary
| Steel Name | C | Mn | Ni | Cr | N |
|---|---|---|---|---|---|
| 21-2N | 0.5 | 8 | 2 | 20 | 0.3 |
| SUH35 | 0.5 | 9 | 3.5 | 21 | 0.4 |
| 23-8N | 0.3 | 2 | 8 | 23 | 0.3 |
Physical property
Condition of heat treatment temperature
High temperature mechanical properties
Heat treatment of test specimen
21-2N:1100℃,WQ／750℃,AC，SUH35:1100℃,WQ／750℃,AC
23-8N:1100℃,WQ／800℃,AC
High temperature corrosion resistance
Heat-resistant steel for exhaust valves (high alloy)
Composition summary
Physical property
Condition of heat treatment
High temperature mechanical properties
Heat treatment of test specimen
NCF751*:1100℃,WQ／850℃,AC／710℃,AC
NCF80A*:1050℃,WQ／700℃,AC
High temperature corrosion resistance
*NCF751is equivalent of Inconel 751.
*NCF80A is equivalent of Nimonic 80A.
*Inconel and Nimonic is the registered trade make of Special Metals Corporation.