Introduction
AISI 1018 mild/low carbon steel has excellent weldability and produces a uniform and harder case
and it is considered as the best steel for carburized parts. AISI 1018 mild/low carbon steel offers a good balance of toughness, strength and ductility. Provided with higher mechanical properties, AISI 1018 hot rolled steel also includes improved machining
characteristics and Brinell hardness.
Specific manufacturing controls are used for surface preparation, chemical composition, rolling
and heating processes. All these processes develop a supreme quality product that are suited to fabrication processes such as welding, forging, drilling, machining, cold drawing and heat treating.
Chemical
Composition
|
Element |
Content |
| Carbon, C |
0.14 - 0.20 % |
| Iron, Fe |
98.81 - 99.26 % (as remainder) |
| Manganese, Mn |
0.60 - 0.90 % |
| Phosphorous, P |
≤ 0.040 % |
| Sulfur, S |
≤ 0.050 % |
Physical
Properties
|
Physical Properties |
Metric |
Imperial |
| Density |
7.87 g/cc |
0.284 lb/in3 |
Mechanical
Properties
|
Mechanical Properties |
Metric |
Imperial |
| Hardness, Brinell |
126 |
126 |
| Hardness, Knoop (Converted from Brinell hardness) |
145 |
145 |
| Hardness, Rockwell B (Converted from Brinell hardness) |
71 |
71 |
| Hardness, Vickers (Converted from Brinell hardness) |
131 |
131 |
| Tensile Strength, Ultimate |
440 MPa |
63800 psi |
| Tensile Strength, Yield |
370 MPa |
53700 psi |
| Elongation at Break (In 50 mm) |
15.0 % |
15.0 % |
| Reduction of Area |
40.0 % |
40.0 % |
| Modulus of Elasticity (Typical for steel) |
205 GPa |
29700 ksi |
| Bulk Modulus (Typical for steel) |
140 GPa |
20300 ksi |
| Poissons Ratio (Typical For Steel) |
0.290 |
0.290 |
| Machinability (Based on AISI 1212 steel. as 100% machinability) |
70 % |
70 % |
| Shear Modulus (Typical for steel) |
80.0 GPa |
11600 ksi |
Electrical
Properties
|
Electrical Properties |
Metric |
English |
Comments |
| Electrical resistivity @0°C (32°F) |
0.0000159 Ω-cm |
0.0000159 Ω-cm |
annealed condition |
| @100 °C/ 212 °F |
0.0000219 Ω-cm |
0.0000219 Ω-cm |
annealed condition |
| @ 200 °C/392 °F |
0.0000293 Ω-cm |
0.0000293 Ω-cm |
annealed condition |
Machining
The machinability of AISI 1018 mild/low carbon steel is graded at 78% of B1112.
Weldability
AISI 1018 mild/low carbon steel can be instantly welded by all the conventional welding processes.
Welding is not recommended for AISI 1018 mild/low carbon steel when it is carbonitrided and carburized.
Low carbon welding electrodes are to be used in the welding procedure, and post-heating and pre-heating
are not necessary. Pre-heating can be performed for sections over 50 mm. Post-weld stress relieving also has its own beneficial aspects like the pre-heating process.
Heat
Treatment
The heat treatment for AISI 1018 mild/low carbon steel consists of the following processes:
Normalizing