4140 Quench & Tempered Stress Relieved Steel Round Bar
Quenching and tempering refers to a heat treatment process used to improve the comprehensive mechanical properties of steel materials. That is, after quenching, it is then subjected to high temperature tempering.
The purpose is to make steel parts obtain a good combination of strength and toughness, which has both high strength and excellent toughness, plasticity, and cutting performance.
Some alloy steels or low alloy steels must be quenched and tempered to obtain good comprehensive properties. These steels can also be called quenched and tempered steels.
Ductile iron quenched and tempered can improve both strength and hardness and wear resistance.
AISI 4140 SCM440 EN19 42CrMo4 steel is a Chromium-Molybdenum through-hardening steel of medium hardenability. It is a general purpose high-tensile steel with medium strength level and good impact properties.
1.Sizes we can offer for QT steel round bars
| Delivery condition |
Diameter ranges |
| Hot tolled |
M12-M310 |
| Hot rolled+Q&T(Quenched and tempered) |
M12-M310. |
| Cold drawn +Q&T(Quenched and tempered) |
M10-M100 |
| Peeled / Peeled+Q&T |
M10-M100 |
| Forged/Forged+Heat treatment. |
M250-M1000 |
2.Equivalent steel grade and chemical composition :
| Standard |
Grade |
C |
Si |
Mn |
P |
S |
Cr |
Mo |
| ASTM A29 |
4140 |
0.38-0.43 |
0.15-0.35 |
0.75-1.00 |
≤ 0.035 |
≤ 0.04 |
0.8-1.1 |
0.15-0.25 |
| |
42CrMo4 |
0.38-0.45 |
≤ 0.4 |
0.6-0.90 |
≤ 0.025 |
≤ 0.035 |
0.9-1.2 |
0.15-0.30 |
| EN10083 |
1.7225 |
| JIS G4105 |
SCM440 |
0.38-0.43 |
0.15-0.35 |
0.6-0.85 |
≤ 0.035 |
≤ 0.04 |
0.9-1.2 |
0.15-0.30 |
| GB 3077 |
42CrMo |
0.38-0.45 |
0.17-0.37 |
0.5-0.80 |
≤ 0.035 |
≤ 0.035 |
0.9-1.2 |
0.15-0.25 |
| BS 970 |
EN19 |
0.35-0.45 |
0.15-0.35 |
0.5-0.80 |
≤ 0.035 |
≤ 0.035 |
0.9-1.5 |
0.2-0.40 |
3.Application of AISI 4140 SCM440 EN19 42CrMo4 Q&T steel bars:
Quenching and tempering is widely used for structural parts that require excellent comprehensive performance, especially working under alternating loads, such as automobile shafts and gears, High strength bolts, aircraft engine turbine shafts, compressor disks, etc.
4.Mechanical properties of AISI 4140 SCM440 EN19 42CrMo4 Q&T steel bars:
(Chinese standard ) We can catch different property as per your requirements
| Tensile Strength |
Yield Strength |
Elongation |
Reduction |
Impacting Energy |
HBW |
| Rm,MPa |
Rel,MPa |
A,% |
Z,% |
Aku,J |
≤ |
| |
|
|
|
|
After annealing |
| ≥1080 |
≥930 |
≥12 |
≥45 |
≥63 |
217 |
5.Quality control
1.Processing Line:
Iron - hot metal pretreatment - Converter - Refining --VD / RH- - Continuous Casting - Hot Rolling (KOCKS) - heat --UT Check - Processing and Distribution Center
Electric Furnace - Refining --VD / RH- - Continuous Casting - Hot Rolling (KOCKS) - heat --UT Check - Processing and Distribution Center
2.Gas content level:O2 - <20 ppm H2 - <2 ppm N2- <100 ppm
3.Grain Sizes:5-8
6.Delivery time of steel bar:
7-10days of stock,30 days after order confirmed for new produced .
7.Payment term:TT or LC
8.Free sample:Yes
9.steel bar Inspection: Spectral Tested, Microstructure Tested,Hardness Test,Macrostructure Test,UT test and so on.
10.Mark: Heat Number,Weight,Sizes,Grade,etc
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