NAS 750；Heat Resistant Nickel Base Alloy
Characteristics of NAS 750
A precipitation hardening alloy with a nickel base, NAS 750 provides corrosion resistance along with superior tensile strength, creep rupture and fatigue resistance up to 700℃. It is used in a wide range of applications such as aircraft and power generation gas turbine parts, nuclear reactor parts, pressure vessels, heat-resistant springs and hot working tools.
Chemical Composition
(%)
| - | C | Si | Mn | P | S | Ni | Cr | Cu | Co | Al | Ti | Fe | Nb+Ta | Ta |
| JIS G4902 NCF750 |
≦0.08 | ≦0.50 | ≦1.00 | ≦0.030 | ≦0.015 | ≧70.00 | 14.0～ 17.0 |
≦0.50 | - | 0.40～ 1.00 |
2.25～ 2.75 |
5.00～ 9.00 |
0.70～ 1.20 |
- |
| SAE AMS 5542 |
≦0.08 | ≦0.50 | ≦1.00 | - | ≦0.01 | ≧70.00 | 14.0～ 17.0 |
≦0.50 | ≦1.00 | 0.40～ 1.00 |
2.25～ 2.75 |
5.00～ 9.00 |
0.70～ 1.20 |
≦0.05 |
| NAS 750 | 0.02 | 0.09 | 0.05 | 0.006 | 0.001 | 73.98 | 15.27 | 0.01 | 0.04 | 0.73 | 2.46 | 6.47 | 0.82 | 0.00 |
Corresponding Standard
NAS 750 corresponds to the following standard.
JIS G4902 / NCF750
SAE AMS 5542
Mechanical properties of solution heat treated NAS 750
| Grade | 0.2% Proof stress (MPa) |
Tensile strength (MPa) |
Elongation （％） |
Hardness （HV） |
G.S.N. |
| JIS G4902 NCF750 S1 | - | ≦890 | ≧40 | ≦335 | - |
| SAE AMS 5542 | ≦448 | ≦896 | ≧40 | - | ≧2.5 |
| NAS 750 ( 5.6mmt) Solution heat treated |
429 | 818 | 48 | 175 | 6.5 |
Mechanical properties of aging hardened NAS 750 following solution heat treatment
| Grade | 0.2% Proof stress (MPa) |
Tensile strength (MPa) |
Elongation （％） |
Hardness （HV） |
| JIS G4902 NCF750 H1 | ≧615 | ≧960 | ≧8 | ≧270 |
| NAS 750 (5.6mmt) JIS H1 Aging treated* |
754 | 1168 | 25 | 365 |
| SAE AMS 5542 | ≧689 | ≧1069 | ≧20 | ≧30HRC (≧302HV) |
| NAS 750 (5.6mmt) 700℃×20hr Aging treated** |
876 | 1230 | 25 | 391 |
*JIS H1 treatment: Holding at 800℃～830℃ for 24 hours followed by air cooling to room temperature → Holding at 690℃～720℃ for 20 hours followed by rapid cooling.
**AMS 5542 treatment: Holding at 704℃±14℃ for 20 hours followed by rapid cooling.
