Product Description





structural carbon steel :45# with details in under sheet :
| Standard No. | Alloy No. | Chemical compositions(%) | ||||||
| C | Cr | Mn | Ni | P | S | Si | ||
| GB/T699-1999 | 45# | 0.42~0.50 | ≤0.25 | 0.50~0.80 | ≤0.25 | ≤0.035 | ≤0.035 | 0.17~0.37 |
| Mechanical Property |
Tensile Strength(Mpa) | Yeild Strength(Mpa) | Elongation(%) | Contraction of area Z(%) | ||||
| ≥600 | ≥355 | ≥16 | ≥40 | |||||
The correlation between properties and parameters-S45C (JIS)-SAE1045(Aisi)-SM45 of No. 45 steel(45 steel) was studied:
No. 45 steel is a carbon structural steel with 0.45% carboncontent. It is characterized by low price, good cutting performance, high hardness after quenching, good strength, toughness and wear resistance after quenching and temperingtreatment, is widely used in manufacturing structural partsand low-grade plastic mold. "45 steel" is a popular name, thesymbol is generally recorded as"45 #". In fact GB standardsteel number is"45", it is not a sequential number, read as"45steel" is not very accurate. Ingredient code 45 steels of similar designation are S45C (JIS) and 1045(Aisi) . In addition, ourcountry metallurgical technology standard has SM45 brandnumber to express the plastic mold use specially. Comparedwith 45 steel, SM45 has lower phosphorus and sulfur contentand better steel purity.
| Standards | YB/T 094 | AISI | JIS G4051 |
| Alloy No. | SM45 | 1045 | S45C |
| C | 0.42-0.48 | 0.43-0.50 | 0.42-0.48 |
| Si | 0.17-0.37 | 0.15-0.35 | |
| Mn | 0.50-0.80 | 0.60-0.90 | 0.60-0.90 |
| P | <0.030 | <0.030 | <0.030 |
| S | <0.035 | <0.035 | <0.035 |
Recommended process specification for heat treatment andhardness: quenching temperature 820 - 860" C, water-oroil-cooled, hardness 250 HRC. Recommended tempering pro-cess specifcation: tempering temperature is 500 - 560" C, aircooling, hardness is 25 - 33HRC. Tempering in this temperature range is the tempering treatment, Quenching and tempering make the strength, plasticity and toughness of 45 steelget a good balance, the comprehensive performance is good,can adapt to the alternating load environment. After quench-ing and tempering, the surface hardness of 45 steel is low anddoes not wear well. So commonly used quenching and tempering + surface quenching to improve the surface hardnessof parts.
| Tempering temperature | After quenching | Unit centigrade | |||||
| 200 | 300 | 400 | 500 | 550 | 600 | ||
| Hardness HRC |
57 | 55 | 50 | 41 | 33 | 26 | 22 |
| Mechanical properties (GB/T 699-1999) | |||
| Sample size | mm | 25 | |
| Heat treatments recommended | Normalizing | ºC | 850 |
| Quenching | ºC | 840 | |
| Tempering | ºC | 600 | |
| Mechanical properties | Tensile strongth | Mpa | ≥600 |
| Strong yield | Mpa | ≥355 | |
| Elongation | Mpa | ≥16 | |
| Section shrinkago | Mpa | ≥40 | |
| Impact | Mpa | ≥39 | |
| Hardness of delivery | HB | ≤229 | |
| HB | ≤197 | ||
Main Products






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