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E: enquiry@qilumetal.com
E: enquiry@qilumetal.com
No. 18 Xiangfu Middle Road,Yuhua District, Changsha City
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| Quantity: | |
|---|---|
37Cr4
Country | USA | Europe |
Standard | ASTM A29 | EN10250-3 |
Grade | 5135 | 37Cr4/1.7034 |
2: Chemical composition
Grade | C | Si | Mn | P | S | Cr |
5135 | 0.33-0.38 | 0.15-0.35 | 0.60-0.80 | 0.035Max | 0.040Max | 0.80-1.05 |
37Cr4/1.7034 | 0.34-0.41 | 0.40Max | 0.60-0.90 | 0.035Max | 0.035Max | 0.90-1.20 |
3: Mechanical properties .
Mechanical properties for 37Cr4 quenching and tempering alloy steel according to EN10083-3.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤8 | 950-1150Mpa | 750Mpa Min | 11% Min | 35% Min | / |
16＜d≤40 8＜t≤20 | 850-1000Mpa | 630Mpa Min | 13% Min | 40%Min | 35J Min |
40＜d≤100 20＜t≤60 | 750-900Mpa | 510Mpa Min | 14% Min | 40%Min | 35J Min |
Sampling and preparation of test pieces for 37Cr4 quenching and tempering steel.
1): According to EN10083-1, all samples shall be taken at a distance of 12.5mm below the heat treated surface
2): As stipulated in the contract between buyer and seller.
Mechanical properties for 37Cr4 open die forgings steel according to EN10250-3
Size range | Tensile strength | Yield strength | Alongation | Impact value at RT/J | ||
d≤70 | 750Mpa Min | 510Mpa Min | 14% Min | 35J Min | ||
Sampling and preparation of test pieces for steel forging.
1: According to EN10250-1, all samples shall be taken at a distance of 4/T below the heat treated surface (with a minimum of 20mm and a maximum of 80mm), and t/2 from the end (where t is the equivalent thickness of the thickness of the ruling section of the forging at the time of heat treatment.
2: As stipulated in the contract between buyer and seller.
4: Surface hardness and hardenability.
Heat Treatment | Hardness |
| Treated to improve shearability (+S) | HB255Max |
Soft annealed (+A) | HB235Max |
Quenched and tempred (+QT) | HRC28-32(Common Range) |
Where the steel is ordered by using the symbols for normal (+H) or restricted (+HL, +HH) hardenability requirements, the hardenability values should apply below:
Distance in mm from quenched end | ||||||||||||||||
Distance | 1.5 | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | |
Hardness In HRC + H | max | 59 | 59 | 58 | 57 | 55 | 52 | 50 | 48 | 42 | 39 | 37 | 36 | 35 | 34 | 33 |
min | 51 | 50 | 48 | 44 | 39 | 36 | 33 | 31 | 26 | 24 | 22 | 20 | / | / | / | |
Hardness In HRC + HH | max | 59 | 59 | 58 | 57 | 55 | 52 | 50 | 48 | 42 | 39 | 37 | 36 | 35 | 34 | 33 |
min | 54 | 53 | 51 | 48 | 44 | 41 | 39 | 37 | 31 | 29 | 27 | 25 | 24 | 23 | 22 | |
Hardness In HRC + HL | max | 56 | 56 | 55 | 53 | 50 | 47 | 44 | 42 | 37 | 34 | 32 | 31 | 30 | 29 | 28 |
min | 51 | 50 | 48 | 44 | 39 | 36 | 33 | 31 | 26 | 24 | 22 | 20 | / | / | / | |
Scatter bands for the Rockwell - C hardness in the end quench hardenability test.
5: Supply size & Tolerance & Stock size
Product type | Size range | Length |
Hot rolled bar | Φ16-Φ300mm | 6000-9000mm |
Hot forged bar | Φ140-Φ800mm | 3000-5800mm |
Hot rolled plate/sheet | T:12-120mm; W:1500-2500mm | 2000-5800mm |
Hot Forged block | T: 80-800mm; W: 100-2500mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
Qilu steel stock hot rolled bar and forged bars more than ten thousands tons every month, below our our stock size.
1): Stock diameter for hot rolled bar
16 | 18 | 19 | 20 | 22 | 25 | 28 | 30 | 32 | 35 | 38 | 40 | 42 | 45 | 48 |
50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 105 | 110 | 115 | 120 |
125 | 130 | 140 | 150 | 160 | 170 | 180 | 190 | 200 | 210 | 220 | 230 | 240 |
Since the stocks change everyday, if you want to know our stock available information, please contact our salesman.
6：Forging processing
Preheat temperature: 700-800℃
Put the 37Cr4 ingot into the furnace and heat to 1150-1200℃
Cooling in the sand after forged
7: Heat treatment
Soft annealed:
Heat 37Cr4 steel to 850-880℃ in the furnace
Slow furnace cooling. The cooling rate must be controlled, typically recommended at ≤ 20°C/hour for slow cooling to approximately 600°C, after which the product can be removed from the furnace for air cooling
Normalized:
Heat 37Cr4 steel to 870-890℃ in the furnace
Soak at this temperature in the furnace
Cooling in the air
Quenching and tempering:
Heat 37Cr4 steel to 825-865℃ in the furnace
Soak at this temperature in the furnace
Quench in water or oil
Temper steel at 540-680℃ in the furnace
Take out of 37Cr4 steel from furnace and cool in the air.
Remark: The conditions given above are for guidance, at the temperatures at the lower end of the range are generally applicable to hardening in water and those at the upper end for hardening in oil.
8: Weldability
The weldability of 37Cr4 steel is poor, with its core limiting factor being the chemical composition. Its carbon content of 0.34–0.41% significantly exceeds the commonly accepted threshold of 0.25% for excellent weldability, while the chromium content further enhances hardenability. The combined effect of these factors makes the heat-affected zone highly susceptible to forming hard, brittle martensitic structures, rendering the joint highly sensitive to hydrogen-induced cold cracks.
9：Application
37Cr4 is a chromium alloy structural steel. Due to its excellent strength, moderate toughness, and outstanding hardenability, it is widely used in manufacturing critical mechanical components subjected to high dynamic loads, friction, or moderate impact loads after undergoing quenching and tempering heat treatment. Its primary application areas and typical components include:
1. Automotive and Commercial Vehicle Sector
Transmission Systems: Transmission gears, drive shafts, universal joints, synchronizer rings
Engine Systems: Connecting rods, piston rods, camshafts, valve rocker arms
Chassis Systems: Steering knuckles, high-strength bolts, leaf spring pins
2. General Machinery and Equipment Manufacturing
Gears and shaft components: Various gears in industrial gearboxes, drive shafts, spindles, splined shafts
Connecting and transmission components: High-strength bolts, studs, pins, connecting rods
Hydraulic and construction machinery components: Hydraulic rods, pistons, high-stress structural parts in compact excavators and tractors
3. Other Industrial Applications
Components for load-bearing parts in machine tools
Transmission and steering components for agricultural machinery
Base material for manufacturing molds (e.g., plastic molds)
Country | USA | Europe |
Standard | ASTM A29 | EN10250-3 |
Grade | 5135 | 37Cr4/1.7034 |
2: Chemical composition
Grade | C | Si | Mn | P | S | Cr |
5135 | 0.33-0.38 | 0.15-0.35 | 0.60-0.80 | 0.035Max | 0.040Max | 0.80-1.05 |
37Cr4/1.7034 | 0.34-0.41 | 0.40Max | 0.60-0.90 | 0.035Max | 0.035Max | 0.90-1.20 |
3: Mechanical properties .
Mechanical properties for 37Cr4 quenching and tempering alloy steel according to EN10083-3.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤8 | 950-1150Mpa | 750Mpa Min | 11% Min | 35% Min | / |
16＜d≤40 8＜t≤20 | 850-1000Mpa | 630Mpa Min | 13% Min | 40%Min | 35J Min |
40＜d≤100 20＜t≤60 | 750-900Mpa | 510Mpa Min | 14% Min | 40%Min | 35J Min |
Sampling and preparation of test pieces for 37Cr4 quenching and tempering steel.
1): According to EN10083-1, all samples shall be taken at a distance of 12.5mm below the heat treated surface
2): As stipulated in the contract between buyer and seller.
Mechanical properties for 37Cr4 open die forgings steel according to EN10250-3
Size range | Tensile strength | Yield strength | Alongation | Impact value at RT/J | ||
d≤70 | 750Mpa Min | 510Mpa Min | 14% Min | 35J Min | ||
Sampling and preparation of test pieces for steel forging.
1: According to EN10250-1, all samples shall be taken at a distance of 4/T below the heat treated surface (with a minimum of 20mm and a maximum of 80mm), and t/2 from the end (where t is the equivalent thickness of the thickness of the ruling section of the forging at the time of heat treatment.
2: As stipulated in the contract between buyer and seller.
4: Surface hardness and hardenability.
Heat Treatment | Hardness |
| Treated to improve shearability (+S) | HB255Max |
Soft annealed (+A) | HB235Max |
Quenched and tempred (+QT) | HRC28-32(Common Range) |
Where the steel is ordered by using the symbols for normal (+H) or restricted (+HL, +HH) hardenability requirements, the hardenability values should apply below:
Distance in mm from quenched end | ||||||||||||||||
Distance | 1.5 | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | |
Hardness In HRC + H | max | 59 | 59 | 58 | 57 | 55 | 52 | 50 | 48 | 42 | 39 | 37 | 36 | 35 | 34 | 33 |
min | 51 | 50 | 48 | 44 | 39 | 36 | 33 | 31 | 26 | 24 | 22 | 20 | / | / | / | |
Hardness In HRC + HH | max | 59 | 59 | 58 | 57 | 55 | 52 | 50 | 48 | 42 | 39 | 37 | 36 | 35 | 34 | 33 |
min | 54 | 53 | 51 | 48 | 44 | 41 | 39 | 37 | 31 | 29 | 27 | 25 | 24 | 23 | 22 | |
Hardness In HRC + HL | max | 56 | 56 | 55 | 53 | 50 | 47 | 44 | 42 | 37 | 34 | 32 | 31 | 30 | 29 | 28 |
min | 51 | 50 | 48 | 44 | 39 | 36 | 33 | 31 | 26 | 24 | 22 | 20 | / | / | / | |
Scatter bands for the Rockwell - C hardness in the end quench hardenability test.
5: Supply size & Tolerance & Stock size
Product type | Size range | Length |
Hot rolled bar | Φ16-Φ300mm | 6000-9000mm |
Hot forged bar | Φ140-Φ800mm | 3000-5800mm |
Hot rolled plate/sheet | T:12-120mm; W:1500-2500mm | 2000-5800mm |
Hot Forged block | T: 80-800mm; W: 100-2500mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
Qilu steel stock hot rolled bar and forged bars more than ten thousands tons every month, below our our stock size.
1): Stock diameter for hot rolled bar
16 | 18 | 19 | 20 | 22 | 25 | 28 | 30 | 32 | 35 | 38 | 40 | 42 | 45 | 48 |
50 | 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 105 | 110 | 115 | 120 |
125 | 130 | 140 | 150 | 160 | 170 | 180 | 190 | 200 | 210 | 220 | 230 | 240 |
Since the stocks change everyday, if you want to know our stock available information, please contact our salesman.
6：Forging processing
Preheat temperature: 700-800℃
Put the 37Cr4 ingot into the furnace and heat to 1150-1200℃
Cooling in the sand after forged
7: Heat treatment
Soft annealed:
Heat 37Cr4 steel to 850-880℃ in the furnace
Slow furnace cooling. The cooling rate must be controlled, typically recommended at ≤ 20°C/hour for slow cooling to approximately 600°C, after which the product can be removed from the furnace for air cooling
Normalized:
Heat 37Cr4 steel to 870-890℃ in the furnace
Soak at this temperature in the furnace
Cooling in the air
Quenching and tempering:
Heat 37Cr4 steel to 825-865℃ in the furnace
Soak at this temperature in the furnace
Quench in water or oil
Temper steel at 540-680℃ in the furnace
Take out of 37Cr4 steel from furnace and cool in the air.
Remark: The conditions given above are for guidance, at the temperatures at the lower end of the range are generally applicable to hardening in water and those at the upper end for hardening in oil.
8: Weldability
The weldability of 37Cr4 steel is poor, with its core limiting factor being the chemical composition. Its carbon content of 0.34–0.41% significantly exceeds the commonly accepted threshold of 0.25% for excellent weldability, while the chromium content further enhances hardenability. The combined effect of these factors makes the heat-affected zone highly susceptible to forming hard, brittle martensitic structures, rendering the joint highly sensitive to hydrogen-induced cold cracks.
9：Application
37Cr4 is a chromium alloy structural steel. Due to its excellent strength, moderate toughness, and outstanding hardenability, it is widely used in manufacturing critical mechanical components subjected to high dynamic loads, friction, or moderate impact loads after undergoing quenching and tempering heat treatment. Its primary application areas and typical components include:
1. Automotive and Commercial Vehicle Sector
Transmission Systems: Transmission gears, drive shafts, universal joints, synchronizer rings
Engine Systems: Connecting rods, piston rods, camshafts, valve rocker arms
Chassis Systems: Steering knuckles, high-strength bolts, leaf spring pins
2. General Machinery and Equipment Manufacturing
Gears and shaft components: Various gears in industrial gearboxes, drive shafts, spindles, splined shafts
Connecting and transmission components: High-strength bolts, studs, pins, connecting rods
Hydraulic and construction machinery components: Hydraulic rods, pistons, high-stress structural parts in compact excavators and tractors
3. Other Industrial Applications
Components for load-bearing parts in machine tools
Transmission and steering components for agricultural machinery
Base material for manufacturing molds (e.g., plastic molds)
