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.