Nov 20 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
Annealing
Cold Working
Welding
Forging
Forming
Machinability
Heat Treatment
Hot Working
Hardening
Aging
Applications
Introduction
Alloy steels comprise a wide variety of steels with compositions that exceed the limitations of Si, Va, Cr, Ni, Mo, Mn, B and C allocated for carbon steels. In comparison with carbon steels, alloy steels are more responsive to mechanical and heat treatments.
Alloy steels can be used in specific melting and deoxidization processes for particular applications. These steels have elements such as chromium, cobalt, nickel, etc.
Maraging 300 alloy steel is a very high strength iron base, molybdenum, cobalt and nickel alloy. The following datasheet provides an overview of maraging 300 alloy steel.
Chemical Composition
The chemical composition of maraging 300 alloy steel is outlined in the following table.
|
Element |
Content (%) |
|
Iron, Fe |
67 |
|
Nickel, Ni |
18.5 |
|
Cobalt, Co |
9 |
|
Molybdenum, Mo |
4.8 |
|
Titanium, Ti |
0.6 |
|
Aluminum, Al |
0.1 |
|
Silicon, Si |
0.10 |
|
Manganese, Mn |
0.10 |
|
Carbon, C |
0.030 |
|
Zirconium, Zr |
0.01 |
|
Phosphorous, P |
0.010 |
|
Sulfur, S |
0.010 |
|
Boron, B |
0.0030 |
Physical Properties
The following table shows the physical properties of maraging 300 alloy steel.
|
Properties |
Metric |
Imperial |
|
Density |
8.00 g/cm3 |
0.289 lb/in³ |
|
Melting point |
1412.8 °C |
2575°F |
Mechanical Properties
The mechanical properties of annealed maraging 300 alloy steel are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength (@538°C/1000°F) |
1158 MPa |
168000 psi |
|
Yield strength (@strain 0.200 %, temperature 538°C/@strain 0.200 %, temperature 1000°F) |
1056 MPa |
153200 psi |
|
Bulk modulus (typical for steel) |
140 GPa |
20300 ksi |
|
Shear modulus (estimated from elastic modulus) |
73.0 GPa |
10600 ksi |
|
Elastic modulus |
190 GPa |
27600 ksi |
|
Poisson's ratio |
0.3 |
0.3 |
|
Elongation at break (in gage length of 4.5 times the square root of the area, @ 316°C/600 °F) |
12.00% |
12.00% |
|
Reduction of area (@427°C/800°F) |
61.30% |
61.30% |
Thermal Properties
The thermal properties of maraging 300 alloy steel are given in the following table.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@21-480°C/69.8-896°F) |
10.1 µm/m°C |
5.61 µin/in.°F |
|
Thermal conductivity (20°C) |
25.3 W/mK |
176 BTU in/hr.ft².°F |
Other Designations
Equivalent material to maraging 300 alloy steel includes DIN 1.6354.
Fabrication and Heat Treatment
Annealing
Maraging 300 alloy steel can be annealed at 1038°C (1900°F) after cold working and then finally cooled in air.
Cold Working
Maraging 300 alloy steel can be cold worked by conventional methods.
Welding
Maraging 300 alloy steel can be welded by conventional methods.
Forging
Maraging 300 alloy steel can be forged as for stainless 304 alloy.
Forming
Conventional methods are used to readily form maraging 300 alloy steel that has good ductility.
Machinability
Maraging 300 alloy steel has good machinability characteristics.
Heat Treatment
Maraging 300 alloy steel cannot be heat treated for hardening except by aging.
Hot Working
Maraging 300 alloy steel can be hot worked in temperatures ranging 260 to 93°C (500 to 200°F). Age hardening takes place when this alloy steel is exposed to these temperatures for a long time.
Hardening
Maraging 300 alloy steel can be hardened by aging and cold working.
Aging
Maraging 300 alloy steel has high hardness and strength properties and is thus suitable for an aging heat treatment at 482°C (900°F).
Applications
Maraging 300 alloy steel is used for high strength structural applications that include aircraft land gear components.