EN24T & EN 24 Bright Bar Material Properties
| Hardening EN24 | 823/850°C |
|---|---|
| Tempering | 250-375°C |
| Stress Relieving | Heat slowly to 650-670°C |
| Machineability | Excellent |
| Forgeability | Poor |
| Heat Treatment Ability | Poor |
| Surface Condition |
|
| Weldability | Poor |
Hardened and Tempered EN24T Flat Bar For Gears
| Annealing | Heat slowly to 840-860°C (Soak well and allow to cool) |
|---|---|
| Tempering | Tempering between 250-375°C (Heat carefully to a suitable temperature selected by reference to the tempering chart ) |
| Stress Relieving | Heat carefully to 650-670°C (Stress relieving will be beneficial prior to hardening) |
| Hardening | Heat to 830-850°C (Neutral salt bath will reduce the possibility of scaling or decarburisation) |
Table of contents
- BS 970 EN24 Round Bar Specification
- Types of EN 24 Round Bar
- 817M40 Flat Bar Equivalent Grades
- EN24 Steel Bright Bar HSN Code
- Mechanical Properties of EN24T Steel Black Bar
- EN24 Mild Steel Round Bar Thermal Properties
- EN 24 Flat Bright Finish Bar Electrical Properties
- Welding Materials of 817M40T EN24T Steel Bar
- EN 24 Round Bar Surface Finish
- 34CrNiMo6 Steel Bright Bar Stress Tests
- 34CrNiMo6 Round Bar Quenched & Tempered Condition Properties
- Heat Treatment of EN24 Round Bar
BS 970 EN24 Round Bar Specification
| Specification Parameter | Allowed values |
|---|---|
| Item Description | Carbon Steel |
| Tolerances | Not specified, shall be as per relevant standards. |
| Other details and supply conditions | Forged and annealed. |
| Supply length | Standard length for supply: 3-5 mtrs. |
| Conformity to relevant standard | Equivalent grade as 817M40 confirming to BS 970-3 |
| Dimensions | Round Section: 230mm Nom. Dia. |
BS 970 EN24 Round Bar
EN24 Flat Bar
EN24T Steel square bar
EN 24 Rod
EN24T Bright Bar
817M40T EN24T Rectangular Bar
817M40 Flat Bar Equivalent Grades
| Internal Standard | BS | DIN | SAE/AISI | IS | EN |
|---|---|---|---|---|---|
| EN18 | 530A40 | 37Cr4 | 5140 | 40Cr1 | EN18 |
| EN24 | 817M40 | 34CrNiMo6 | 4340 | 40NiCr4Mo3 | EN24 |
| EN19 | 709M40 | 42Cr4Mo2 | 4140,4142 | 40Cr4Mo3 | EN19 |
EN24 Steel Bright Bar HSN Code
| HSN Code | Product Description |
|---|---|
| 7228301 | Bright bars |
| 722830 | Hot-rolled, Hot-drawn or Extruded |
| 722850 | Cold-formed |
Mechanical Properties of EN24T Steel Black Bar
| Mechanical Properties | Annealed | Hardened | Q&T | Spheroidized |
|---|---|---|---|---|
| Brinell Hardness | 190 to 300 | |||
| Elastic Modulus | 190 GPa | |||
| Poisson’s Ratio | 0.29 | |||
| Shear Modulus | 73 GPa | |||
| Tensile Strength | 620 to 1750 MPa | |||
EN24 Mild Steel Round Bar Thermal Properties
| Thermal Properties | Annealed | Hardened | Q&T | Spheroidized |
|---|---|---|---|---|
| Latent Heat of Fusion | 250J/g | |||
| Maximum Temperature | 440°C (820 °F) | |||
| Melting Completion | 1460°C (2660 °F) | |||
| Melting Onset | 1420°C (2580 °F) | |||
| Specific Heat Capacity | 470 J/kg-K (0.11 BTU/lb-°F) | |||
| Thermal Conductivity | 40 W/m-K (23 BTU/h-ft-°F) | |||
| Thermal Expansion | 13 µm/m-K | |||
EN 24 Flat Bright Finish Bar Electrical Properties
| Electrical Properties | Annealed | Hardened | Q&T | Spheroidized |
|---|---|---|---|---|
| Equal Volume | 7.6% IACS | |||
| Equal Weight | 8.7% IACS | |||
Welding Materials of 817M40T EN24T Steel Bar
| Levels | Arc Voltage (V) | Welding Current (A) | Gas Pressure (Bar) |
|---|---|---|---|
| 3 | 22 | 180 | 6 |
| 2 | 20 | 160 | 5 |
| 1 | 18 | 140 | 4 |
34CrNiMo6 Steel Bright Bar Stress Tests
| Property | T | V | W | S | U | X | Y | Z |
|---|---|---|---|---|---|---|---|---|
| Proof Stress(0.2%) Mpa,Min | 635 | 775 | 850 | 555 | 710 | 910 | 990 | 1235 |
34CrNiMo6 Round Bar Quenched & Tempered Condition Properties
| Diameter,mm | Tensile Strength MPa | Yield Strength MPa | Elongation % | Reduction % | Impact,J | Hardness,HB |
|---|---|---|---|---|---|---|
| Φ430 | 960 | 795 | 14 | 48.5 | 86/68/68 | 299 |
| Φ420 | 960 | 790 | 15 | 42.5 | 76/52/50 | 291 |
| Φ450 | 940 | 750 | 18 | 50 | 95/90/110 | 302 |
Heat Treatment of EN24 Round Bar
| Normalizing | 850℃-880℃ (Cool in still air.) |
|---|---|
| Tempering | 660ºC (Tempering process should be followed after quenching immediately) |
| Hardening | 820-850ºC (Heated, Oil quenching is recommended.) |
| Annealing | Soft Annealing : Temperaure 650℃-680℃ |
| Full Annealing : Temperaure 820-850℃ |
EN 24 Round Bar Surface Finish
| Straightness | standard: – wave ≤ 1,5‰ for C content=> 0,25 % and ≤ 1‰ for C content < 0,25 % |
|---|---|
| out of standard : – Ra ≤ 1µm | |
| Surface Defence | defects depth : ≤ 0,01 Ø, equivalent to class 3 EN 10277-1 standard and class 1 UNI 10233-1 standard |
| Surface Finish | standard : – Ra ≤ 3.2 µm |
| out of standard : – wave ≤ 1% | |
| Ends Appearance | Cold Shearing |
Chemical Composition of T Condition Treated EN24T Round Bar For Bolts, Studs And Shafts
| Chemical Composition (weight %) | max. | min |
|---|---|---|
| C | 0.44 | 0.36 |
| Si | 0.4 | 0.1 |
| Mo | 1.4 | 0.2 |
| Mn | 0.7 | 0.45 |
| S | 0.04 | |
| P | 0.035 | |
| Cr | 0.35 | 1 |
| Ni | 1.4 | 1.3 |
Bright Drawn And Hot Rolled EN24T Steel Bar Specification
| BS 970:1955 | EN24T |
|---|---|
| European Standard | EN10277-5 |
| German / DIN | 34CrNiMo6 |
| French AFNOR | 35NCD6 |
| American AISI / SAE 4340 G | 4340 |
| BS 970:1991 | 817M40T |
| German Werkstoff No. | 1.6582 |
UK Standard EN24 Mild Steel Round Bar Stock Sizes From 10mm -115mm Diameter
