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. |