| FOR REQUIREMENTS: | High Fatigue Nitriding Grade |
| MELT PRACTICE: | ESR |
| CORROSION RESISTANCE: | N/A |
| ALTERNATIVE TO: | M-50 Nitralloy N/135 |
| SPECIFICATIONS: | 33CrMoV12-9 UNS: K24340 |
In this field, GKH®W offers the best combination of core properties to withstand structural loads & damage tolerances and surface functions in the case hardened layer. The result on components gives one of the best solutions in the market for contact pressures and fatigue performances.
GKH®W can also be used without nitriding and offers the triple advantage of an excellent combination of mechanical properties, high thermal fatigue and high thermal conductivity.
Benefits of GKH®W
The use of GKH®W covers all the gears design considerations and brings the highest value of this technology:
- Exceptional fatigue bending performance
- Very deep case requirement (0.8mm achieved in 120Hrs nitriding)
- Limited influence of ageing during nitriding on core properties
- Exceptional compromise of core hardness and damage tolerance
- Surface metallurgy with limited depth and favorable compound layer
- Weldable material (EBW for instance) giving the opportunity to avoid mechanical assembly
Typical Applications
GKH®W is used to produce nitrided parts which need to be extremely stable after hardening and tempering. It is particularly suitable for producing parts that undergo special nitriding.
GKH®W has been successfully used for decades in the most critical mechanical components within Aerospace, Motorsports, injection systems, firearms, retaining rings, etc.
- Gears, spindles, machine-tool fittings
- Crankshafts, precision parts, aircraft parts
- Thrust rings, bearing races working up to 400 °C
Comparisons to Other Materials
| Grade | Technology | Case properties | Core properties | Lf case hardened material (Mpa/KSI) | ||||
|---|---|---|---|---|---|---|---|---|
| Operating temperature (°F) | Top hardness (HRC) | Case depth (mm/in) | UTS (Mpa/KSI) | YS0,2 (Mpa/KSI) | K1c (MPa.Vm) | |||
| 9310 Remelted | Carburizing | 300 | 60 | 1.40/.055 | 1150/167 | 900/131 | 120 | 1050/152 |
| AMS 6308 | 390 | 60 | 1.40/.055 | 1172/170 | 965/140 | 126 | / | |
| AMS 6509 | 840 | 62.5 | 1.40/.055 | 1578/229 | 1370/199 | 93 | / | |
| AMS 6475 | Deep nitriding | 840 | 65.50 | 0.45/.018 | 1240/180 | 1150/167 | / | / |
| GKH®W | 840 | 64.70 | 0.70/.028 | 1250/181 | 1060/154 | 180 | 1140/165 | |
| Heat Treatment | UTS | 0.2% YS | E | KV | Surface Hardness | |
|---|---|---|---|---|---|---|
| (MPa / Ksi) | (MPa / Ksi) | (%) | (J /ft.lb) | HRC | ||
| M50 VIM/VAR | 1100°C / Gas, -75°C, 3 x 550°C | Through hardened to HRC: 60 – 63 | ||||
| 9310 VAR & VIM/VAR | 825°C / Oil, -75°C, 150°C | 1150/167 | 900/131 | 14 | 140/103 | 60 |
| M50NIL | 1100°C / Oil, -75°C, 3 x 540°C | 1400/203 | 1200/174 | 15 | 12/9 | 60 |
| GKH® Remelt (W) & VIM/VAR (YW) | 920°C, Oil, 600°C | 1250/181 | 1060/154 | 15 | 130/96 | 65.5 |
| 920°C, Oil, 640°C | 1080/157 | 900/131 | 19 | 170/125 | 65.5 | |
| GKP Remelt (W) & VIM/VAR (YW) | 940°C, Oil, 600°C | 1430/207 | 1280/186 | 14 | 50/37 | 67 |
| 940°C, Oil, 640°C | 1250/181 | 1075/156 | 16 | 80/59 | 67 | |
Chemical Composition
| C | Si | Mn | S | P | Ni | Cr | Mo | V | |
|---|---|---|---|---|---|---|---|---|---|
| min. | 0.29 | 0.10 | 0.40 | / | / | / | 2.80 | 0.70 | 0.15 |
| max. | 0.36 | 0.40 | 0.70 | 0.005 | 0.015 | 0.30 | 3.30 | 1.20 | 0.35 |
Stocking Sizes
Bar: 5.512″ & 6.299″ (140mm & 160mm)
Datasheet and Brochure
