300M S155 Alloy Steel
300M S155 Alloy Steel
Supplying Size:
Rolled: Diameter 40-200mm
Forged: Diameter 80-600mm
300M/S155 is a high performance alloy steel which is a vacuum melted grade, supplied in the normalised and tempered/softened condition to enhance machinability prior to final heat treatment.
Chemical Component:
| C | Si | Mn | P | S | Cr | Mo | Ni | V |
| 0.38-0.46 | 1.45-1.8 | 0.6-0.9 | 0.01 | 0.01 | 0.7-0.95 | 0.3-0.65 | 1.65-2 | 0.05 |
Mechanical Properties:
| Mechanical & Physical Properties | 21 °C |
| Ultimate Tensile Strength /MPa | 1981 |
| 0.2% Yield Strength /MPa | 1672 |
| Reduction of area % | 35 |
| Elongation % | 10 |
| Room Temperature Hardness/ Rockwell C | 58 |
(Normalised at 927 °C for 1 hour+air cool/Austenitised at 871°C for 1 hour + oil quench/Tempered at 302°C for 1 hour+air cool)
| Hardness at Various Tempering Temperature | 204°C | 316°C | 427°C | 538°C | 649°C |
| Hardness / Rockwell C | 53 | 52.5 | 50 | 47 | 35 |
(Austenitised at 871°C for 1 hour + oil quench/Tempered for 2+2 hour+air cool)
Introduce:
It has a combination of ultra high strength, good fatigue resistance and excellent transverse properties, and as such finds many applications in the aerospace industry, such as undercarriage components, gears and shafts.
Standards:
AMS 6417, ASTM A579
Application:
300M/S155 can be used in a variety of applications, here are just a few examples:
Undercarriage components
Gears
Shafts
Aircraft landing gear
High strength bolts
Properties:
Density:
7.85 g/cm^3
Specific Heat Capacity:
448 J/kg*K
Coefficient of Thermal Expansion from -17.8-93°C:
11.34 µm/mm/°C
