COLD FINISHED CARBON STEEL BARS
COMPOSITION OF COLD FINISHED CARBON STEEL BARS
|
Grade
|
Relative
Machinability, Based on 1212 as 100% |
Carbon
% |
Magnesium
% |
Phosphorous
% |
|
4140
Annealed |
65
|
0.38-0.43
|
0.75-1.00
|
0.035 Max
|
|
8620
|
65
|
0.18-0.23
|
0.70-0.90
|
0.035 Max
|
|
Grade
|
Sulfur
% |
Silicon
% |
Nickel
% |
Chromium
% |
Molybdenum
% |
|
4140
Annealed |
0.04 Max
|
0.15-0.35
|
–
|
0.80-1.10
|
0.15-0.25
|
|
8620
|
0.04 Max
|
0.15-0.35
|
0.40-0.70
|
0.40-0.60
|
0.1
|
| CARBON: | Hardening element, strength, and hardness increase with increased carbon content. |
| MANGANESE: | Contributes to strength and hardness, decreases weldability. |
| PHOSPHORUS: | Contributes to strength and hardness, decreases ductility (ability to withstand deformation without rupture). |
| SULFUR: |
Decreases weldability, detrimental to surface quality. |
| SILICON: |
Contributes to strength and hardness, decreases machinability. |
| NICKEL: |
Increases toughness (resistance to impact fracture), broadens heat treatment temperature range. |
| CHROMIUM: |
Promotes hardenability, enhances corrosion resistance. |
| MOLYBDENUM: |
Promotes hardenabilty, broadens heat treatment temperature range. |