24 July 2021 Gear Steel Bar
18CrNiMo7-6 Gear Steel Bar
18CrNiMo7-6 is a German standard alloy steel grade. It has high bending strength, contact fatigue strength, high hardness and wear resistance, high hardness and toughness at the core, and high comprehensive mechanical properties. Widely used in transmission gears, etc.
Equivalent to DIN 1.6587, 17CrNiMo6 , 18CrNiMo7-6 is alloyed case hardening steel for heavy and high strained gear parts with high demands on toughness at core tensile strength of 1050 - 1350 N/mm2.
18CrNiMo7-6 grade steel is an alloyed case hardening steel for heavy and high strained gear parts with high demands on toughness at core.
It has tensile strength of 1050 - 1350 N/mm².
Chemical Composition:
| C | Si | Mn | Ni | P | S | Cr | Mo |
|---|---|---|---|---|---|---|---|
| 0.15~0.21 | ≤0.4 | 0.5~0.9 | 1.4~1.7 | ≤0.025 | ≤0.025 | 1.5~1.8 | 0.25~0.35 |
Mechanical Properties:
18CrNiMo7-6 has many grade, with different heat treatment process, different grade will have different performance on mechanical properties.
Grade 159A - Variant with low sulphur content and high cleanliness demands
Grade 159B - Variant with controlled sulphur content for consistent machinability and +H hardenability
Grade 159Q - Isotropic properties (IQ) and better fatigue strength due to higher cleanliness levels, and a finer size and distribution of non-metallic inclusions
Grade 159X - Variant with controlled sulphur content for consistent machinability and +H hardenability
Grade 159S - Variant with increased sulphur content.
Grade 4761(MoCN216) - Low sulphur variant of Imatra
| Variant | Condition | Format | Dimension [mm] | Yield strength min [MPa] | Tensile strength [MPa] | Elongation A5 [%] | Reduction of area Zmin [%] | Hardness |
|---|---|---|---|---|---|---|---|---|
159A | +QT | Round bar | 30 typical | 780 | 1080-1320 | 8 | - | - |
| Round bar | 63 typical | 690 | 980-1270 | 8 | - | - | - | - |
| 159B | +QT | Round bar | 30 typical | 780 | 1080-1320 | 8 | - | - |
| Round bar | 63 typical | 690 | 980-1270 | 8 | - | - | - | - |
| 159Q | +QT | Round bar | 30 typical | 780 | 1080-1320 | 8 | - | - |
| Round bar | 63 typical | 690 | 980-1270 | 8 | - | - | - | - |
| 159X | +QT | Round bar | 30 typical | 780 | 1080-1320 | 8 | - | - |
| Round bar | 63 typical | 690 | 980-1270 | 8 | - | - | - | - |
| 159S | +QT | Round bar | 30 typical | 780 | 1080-1320 | 8 | - | - |
| Round bar | 63 typical | 690 | 980-1270 | 8 | 0 | - | - | - |
| 4761, MoCN 216 | +AR | Round bar | 25 < 160 | - | - | - | - | < 320 HB |
| +A | Round bar | 25 < 160 | - | - | - | - | < 229 HB | - |
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