EN24 and EN24T Steel

price:
Contact customer service
Heat Treatment
Cold Processing
Hot Working

EN24 and EN24T Steel

EN24 and EN24T Steel

EN24 and EN24T Steel

EN24 is usually supplied in the finally heat treated condition (quenched and tempered to “T” properties) up to a limiting ruling section of 250mm, which is superior to grades 605M36, 708M40 or 709M40 – see properties below.  Please refer to our selection guide for comparisons.

In addition to the above, EN24T is capable of retaining good impact values at low temperatures, hence it is frequently specified for harsh offshore applications such as hydraulic bolt tensioners and shipborne mechanical handling equipment.

 

817M40 (EN24) Specification
Chemical composition
Carbon 0.36-0.44%
Silicon 0.10-0.35%
Manganese 0.45-0.70%
Sulphur 0.040 Max
Phosphorus 0.035 Max
Chromium 1.00-1.40%
Molybdenum 0.20-0.35%
Nickel 1.30-1.70%

 

EN24 is a very high strength steel alloy which is supplied hardened and tempered.

817M40 (EN24) – mechanical properties in “T” condition
Max Stress 850-1000 n/mm2
Yield Stress 680 n/mm2 Min (up to 150mm LRS)
Yield Stress 650 n/mm2 Min (over 150 to 250mm LRS)
0.2% Proof Stress 665 n/mm2 Min (up to 150mm LRS)
0.2% Proof Stress 635 n/mm2 Min (over 150 to 250mm LRS)
Elongation 13% Min (9% if cold drawn)
Impact KCV 50 Joules Min (up to 150mm LRS
Impact KCV 35 Joules Min (over 150 to 250mm LRS)
Hardness 248-302 Brinell (850-1000 n/mm2)

 

EN24 Equivalents
BS970: 1955 EN24
BS970/PD970:
1970 onwards
817M40
European 34CrNiMo6
Werkstoff No. 1.6582
US SAE (AISI) 4340

 

EN24 STEEL Delivery Condition

1.Shape:Round/Square / Flat/Shafts/Rollers/Blocks
2.Surface condition:Black surface/Bright surface
3.Heat Treatment:Normalized/Annealed/QT
4.Straightness:Max 3mm/m(Enhanced straightness may be available on request)
5.Length:3000-5800mm suitable for 20″container.  above 6000mm,suitable for 40″ container
6.Grain Size: 5-8 acc to ASTM E112-96
7.Typcial Hardness:HRC28-32
8.Ultrasonic Standard: Sep1921/ASTM A388/EN 10228-3
9.Non Metallic Inclusion: 2 max acc to ASTM E45 /K4≤20 acc to DIN 50602
10.Forging Ratio: minimum 4 : 1
11.Marking: Grade/Weight/Length/Size/Heat Number

 

EN24 STEEL Heat Treatment

Soft annealing °C Cooling Hardness HB
650-700 slowly max. 280

 

Stress-relief annealing °C Cooling
630 – 650 Furnace

 

1st pre-heating °C 2nd and 3rd Hardening °C Quenching Tempering °C Hardness after Teperature HRC
up to approx. 400 in an air-circulating furnace 780 and 1000 1190 – 1230 Saltbath, at least 520 °C Oil ,Air at least twice 530-560 64 – 66

 

EN24 STEEL Chemical Composition

EN24 steel (En24T steel) and BS970 817M40 material chemical composition is listed in the following table.

Chemical Composition (Cast Analyses ), %
Country (Region) Standard Steel Grade C Si Mn P, ≤ S, ≤ Cr Ni Mo
Britain BS 970-1955 En24 (En24T) 0.35-0.45 0.10-0.35 0.45-0.70 0.050 0.05 0.90-1.40 1.3-1.8 0.20-0.35
BS 970-1991 817M40 0.36-0.44 0.10-0.40 0.45-0.70 0.035 0.04 1.00-1.40 1.3-1.7 0.20-0.35

 

EN24 STEEL Mechanical Properties

En24 (En24T) and 817M40 steel mechanical properties are listed in the following tables including yield strength (yield stress), ultimate tensile strength, shear strength, modulus of elasticity, young’s modulus, etc.

Notes:

1 MPa = 1 N/mm2

1 GPa = 1 kN/mm2

Reference symbols for tensile strength ranges
Symbol Tensile Strength, MPa (ksi)
P 550-700 (80-100)
Q 625-775 (90-112)
R 700-850 (100-123)
S 775-925 (110-134)
T 850-1000 (123-145)
U 925-1075 (134-156)
V 1000-1150 (145-167)
W 1075-1225 (156-177)
X 1150-1300 (167-188)
Y 1225-1375 (177-199)
Z ≥ 1550 (225)

 

En24T, En24 Mechanical Properties
Standard Steel Hardened and tempered condition Limiting ruling section, in (mm) Tensile strength, tons/in2 (Mpa) [ksi], ≥ Yield stress, tons/in2 (Mpa) [ksi], ≥ Elongation, %, ≥ Izod impact, ft lb, ≥ Brinell hardness, HB
BS970-1955 En24 S 6 (152) 50 (772) [112] 38 (587) [85] 20 40 223-277
T 6 (152) 55 (850) [123] 44 (680) [98] 18 40 248-302
U 4 (101) 60 (926) [134] 48 (741) [107] 17 35 269-321
V 2.5 (63.5) 65 (104) [145] 52 (803) [116] 16 35 293-341
W 1.125 (28.5) 70 (1081) [157] 58 (895) [130] 15 30 311-375
X 1.125 (28.5) 75 (1158) [168] 63 (973) [141] 14 25 341-388
Y 1.125 (28.5) 80 (1235) [179] 68 (1050) [152] 14 22 363-415
Z 1.125 (28.5) 100 (1544) [224] 85 (1313) [190] 8 8 ≥ 444

 

BS970 817M40 Steel Mechanical Properties
Standard Steel Tensile strength, Mpa (ksi), ≥ Yield strength, Mpa (ksi), ≥ 0,2 % proof strength Elongation after fracture, 5.65 √S0 , ≥ Impact, Izod (Charpy V-notch impac) in J, ≥ Hardness, HB Diameter across flats or thickness (t), mm Condition
BS 970-1991 817M40 850-1000 (123-145) 650 (94) 635 (92) 13 40 (35) 248-302 150<t≤250 Normalized + turned or ground
850-1000 (123-145) 680 (98) 665 (96) 13 54 (50) 248-302 63<t≤150
925-1075 (134-156) 750 (109) 740 (107) 12 47 (42) 269-331 29<t≤100
1000-1150 (145-166) 850 (123) 835 (121) 12 47 (42) 293-352 13<t≤63
1075-1225 (156-177) 940 (136) 925 (134) 11 40 (35) 311-375 6≤t≤29
1150-1300 (166-188) 1020 (145) 1005 (145) 10 34 (28) 341-401 6≤t≤29
≥ 1550 (225) 1235 (179) 1125 (163) 5 10 (9) 444 ≥ 6≤t≤29
850-1000 (123-145) 700 (101) 680 (98) 9 54 (-) 248-302 63<t≤150 Hardened and tempered + cold drawn or
hardened and tempered + cold drawn + ground
925-1075 (134-156) 770 (111) 755 (109) 9 47 (-) 269-331 29<t≤100
1000-1150 (145-166) 865 (125) 850 (123) 9 47 (-) 293-352 13<t≤63
1075-1225 (156-177) 955 (138) 940 (136) 8 40 (-) 311-375 6≤t≤29
1150-1300 (166-188) 1035 (150) 1020 (150) 7 34 (-) 341-401 6≤t≤29
≥ 1550 (225) 1250 (181) 1235 (179) 3 11 (-) ≤ 444 6≤t≤29
227 Turned, ground or
cold drawn and finally softened

 

EN24 STEEL Heat Treatment

En24 material heat treatment are listed below, including normalizing, hardening and termpering.

Hardening: 830 to 860 °C (1525-1580 °F), oil quench,

Tempering temperature: 550 to 660 °C (1020-1220 °F)

 

En24 Steel Equivalent Grade

BS970 817M40 material or En24T, En24 steel equivalent to European EN (German DIN EN, French NF EN), ISO, Japanese JIS and Chinese GB standard (for reference).

En24T, En24 and 817M40 Steel Equivalent
Britain European Union ISO China US Japan
Standard Steel name Standard Steel name (Steel number) Standard Grade Standard Grade Standard Grade (UNS) Standard Grade
BS970-1955;
BS970-1991
En24;
817M40
EN 10083-3 34CrNiMo6 (1.6582) ISO 683-18 34CrNiMo6 GB/T 3077 34Cr2Ni2Mo

 

EN24 is a very popular grade of through-hardening alloy steel, which is readily machinable in the “T” condition. (Refer to our machinability guide). EN24T is most suitable for the manufacture of parts such as heavy-duty axles and shafts, gears, bolts and studs.  EN24T can be further surface-hardened typically to 58-60 HRC by induction or nitride processes, producing components with enhanced wear resistance.

EN24 sections larger than 250mm may still be available in the quenched and tempered condition, but it should be noted that a fall-off in mechanical properties may be apparent approaching the centre of the bar.

It is therefore recommended that larger sizes are supplied in the annealed (softened) condition, and that quenching and tempering is carried out after initial stock removal.  This should achieve better mechanical properties towards the core.

 

EN24 STEEL VERY HIGH STRENGTH

The grade is a nickel chromium molybdenum combination – this offers high tensile steel strength, with good ductility and wear resistance characteristics. With relatively good impact properties at low temperatures, EN24 is also suitable for a variety of elevated temperature applications.

 

EN24 STEEL SUITABILITY

EN24 engineering steel is easy to treat and temper and is supplied hardened and tempered. The alloy offers a good combination of strength, ductility and wear resistance. It is a very high strength alloy engineering steel.

 

EN24 STEEL TYPICAL APPLICATIONS

For all metal-cutting tools for roughing or finishing such as twist drills, diverse milling cutters, thread dies, broaches, reamers, countersinks, thread chasers, circular saw segments, shaping tools and woodworking tools. Also highly suitable for cold-forming tools such as cold extrusion rams and dies, as well as cutting and precision cutting tools, plastic moulds with elevated wear resistance and screws.Commercial applications for this engineering material include:

High strength shafts

Punches & dies

Drill bushings

Retaining rings

Gears

 

EN24 Steel Quality Certification

A material test report(Inspection Certificate EN 10204 3.1) will be provided, documenting the following:
1.Chemical analysis
2.Mechanical properties
3.Surface hardness
4.Non Metallic Inclusion
5.Heat Treatment Process
6.Grain size
7.Forging ratio
8.NDE test method/criteria