1. Combinations of delivery conditions
Table 1 Combinations of delivery conditions, product shapes, and conformity requirements
Table 2 Surface quality in delivery condition
| Oberflächenbeschaffenheit im Lieferzustand | Symbol | Bar | Rolled wire | Wire | |
|---|---|---|---|---|---|
| Falls nicht anders vereinbart | hot-rolled | none or +AR | X | X | - |
| Besonderer Oberflachenzustand,der nach Vereinbarung geliefert wird | cold-drawn | +C | - | - | X |
| after-drawn | +LC | X | - | X | |
| rolled peeled | +PE | X | X | X | |
2. Chemical composition
Table 3 Chemical composition of non-boron steel grades, cast analysis, mass fraction (%)
| Steel grade | C b | Si max.a | Mn | P max | S | Cr | Mo | CNi max. | Cu Max. | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Abbreviated name | Material number | |||||||||||
| 25CrMo4 25CrMoS4 34CrMo4 37CrMo4 42CrMo4 42CrMoS4 | 1.7218 1.7213 1.7220 1.7202 1.7225 1.7227 | 0,22 bis 0,29 0,22 bis 0,29 0,30 bis 0.37 0,35 bis 0,40 0,38 bis 0,45 0,38 bis 0,45 | 0,30 0,30 0,30 0,30 0,30 0,30 | 0,60 bis 0,90 0,60 bis 0,90 0,60 bis 0,90 0,60 bis 0,90 | 0,025 0,025 0,025 0,025 0,025 0,025 | 0,025 max. 0,020 bis 0,040 0,025 max 0,025 max. 0,025 max. 0,020 bis 0,040 | 0,90 bis 1,20 0,90 bis 1,20 0,90 bis 1,20 0,90 bis 1,20 | 0.15 to 0.30 0.15 to 0.30 0.15 to 0.30 0.15 to 0.30 0.15 to 0.30 0.15 to 0.30 | 0,25 0,25 0,25 0,25 0,25 0,25 | 0,25 0,25 0,25 0,25 0,25 0,25 | ||
| NOTE 1 Elements not listed in this table should not be intentionally added to the steel, except for final refining of the melt, without the purchaser’s approval. All precautions must be taken to prevent the introduction of such elements from scrap and other materials used in production that could impair hardenability, mechanical properties, and serviceability. NOTE 2 For steels with hardenability requirements [see Tables 9 to 11], smaller deviations from the specified limits are permissible (with the exception of sulfur and phosphorus), provided that, for carbon, they do not exceed 01 %, and for the other elements, they do not surpass the values given in Table 5. NOTE 3 To enhance the efficiency of cold heading, it is possible to add 0.020 % up to 0.050 % of aluminum. | ||||||||||||
Table 4 Chemical composition of boron-alloyed steels. Cast analysis, mass fraction %
Table 5 Permissible deviations between product analysis and the cast analysis limits specified in Tables 3 and 4
3. Mechanical properties
Table 7 - Mechanical properties of boron-free alloy steels
| Steel grade | Diameter | Delivery condition | |||||||
|---|---|---|---|---|---|---|---|---|---|
| +AC or +AC+PE | +AC+C+AC | +AC+C+AC+LC | |||||||
| Abbreviated name | Material number | Over mm | bis mm | Rm max MPa | Z min % | Rm max MPa | Z min % | Rm max MPa | Z min % |
| 25CrMo4 25CrMoS4 | 1.7218 1.7213 | 2 | 5 | 570 | 62 | 610 | 60 | ||
| 5 | 40 | 580 | 60 | 560 | 62 | 600 | 60 | ||
4. Hardenability requirements
Table 9 - Hardness limits for boron-free steel grades with (normal) hardenability requirements (H grade; see 6.4.1)
| Steel short name | rte Material number | symbol | Austenitizing temperature C+5°℃ | Range limit | Hardness in HRC Distance from the quenched end face in mm | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 13 | 15 | 20 | 25 | 30 | |||||
| 25CrMo4 25CrMoS4 | 1.7218 | +H | 850 | max. | 52 | 52 | 51 | 50 | 48 | 46 | 43 | 41 | 37 | 35 | 33 | 32 | 31 | 31 | 31 | |
| 1.7213 | min. | 44 | 43 | 40 | 37 | 34 | 32 | 29 | 27 | 23 | 21 | 20 | ||||||||
| min. | 54 | 54 | 54 | 54 | 54 | 54 | 54 | 54 | 53 | 52 | 52 | 50 | ||||||||
Table 10 - Hardness limits for boron-free steel grades with narrow hardenability requirements (HH and HL grades; see 6.4.2)
| Steel grade | Symbol | austenitizing temperature °C ± 5℃ | Range limit | hardenability in HRC, distance from the quenched end face in mm | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Abbreviated name | Material number | ||||||||||||||||||
| 1,5 | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 20 | 25 | 30 | 35 | 40 | A | 50 | |||||
| 25CrMo4 25CrMoS4 | 1.7218 | +HH | 850 | max. | 52 | 52 | 51 | 50 | 48 | 46 | 43 | 41 | 37 | 35 | 33 | 32 | 31 | 31 | 31 |
| 1.7213 | min | 47 | 46 | 44 | 41 | 39 | 37 | 34 | 32 | 28 | 26 | 24 | 23 | 22 | 22 | 22 | |||
| min | 49 | 49 | 48 | 45 | 42 | 39 | 36 | 34 | 30 | 28 | 27 | 26 | 25 | 24 | 24 | ||||
Table 12 Maximum diameter to achieve at least 90% martensite in core hardness testing (+ CH variety)
| Steel grade | Symbol | austenitizing temperature in the core hardness test °C ± 5℃ | minimum core hardness (90 % martensitic structure) HRC | maximum diameter to ensure 90% martensite in the core [mm] | |
|---|---|---|---|---|---|
| Abbreviated name | Material number | ||||
| 25CrMo4 25CrMoS4 34CrMo4 37CrMo4 42CrMo4 42CrMoS4 | 1.7218 1.7213 1.7220 1.7202 1.7225 1.7227 | +CH +CH +CH +CH +CH +CH | 850 850 850 850 850 850 | 41 41 45 48 50 50 | 13 13 18 18 21 21 |
| a As a guideline, an austenitizing time of at least 30 minutes is recommended. b The specified maximum diameters are those achievable with the lowest hardenability for the respective steel grade, given the minimum carbon content. When using +HH steel grades, the maximum diameter may be increased | |||||