34CrAlMo5-10, 41CrAlMo7-10, 1.8509, 1.8507 - structural steel for nitriding according to PN-H-84030-03, EN 10085.
| Standard | Steel Grade | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | |||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Mo: | Ni: | Al: | |
| EN/DIN | 41CrAlMo7-10 - 41CrAlMo7 - 1.8509 | ||||||||
| 0.38 - 0.45 | 0.4 - 0.7 | <0.4 | <0.025 | <0.035 | 1.5 - 1.8 | 0.20 - 0.35 | - | 0.8 - 1.2 | |
| EN/DIN | 34CrAlMo5-10 - 34CrAlMo5 - 1.8507 | ||||||||
| 0.30 - 0.37 | 0.4 - 0.7 | <0.4 | <0.025 | <0.035 | 1.0 - 1.3 | 0.15 - 0.25 | - | 0.8 - 1.2 | |
| PN | 38HMJ | ||||||||
| 0.35 - 0.42 | 0.3 - 0.6 | 0.17 - 0.37 | <0.025 | <0.025 | 1.35 - 1.65 | 0.15 - 0.25 | <0.25 | 0.7 - 1.1 | |
| NF | 40CAD612 | ||||||||
| 0.38 - 0.45 | 0.5 - 0.8 | <0.4 | <0.030 | <0.035 | 1.5 - 1.8 | 0.25 - 0.40 | - | 0.8 - 1.2 | |
| GOST | 38Х2МЮА | ||||||||
| 0.35 - 0.42 | 0.3 - 0.6 | 0.20 - 0.45 | <0.025 | <0.015 | 1.35 - 1.65 | 0.15 - 0.25 | <0.30 | 0.7 - 1.1 | |
| BS | 905M39 - EN41B | ||||||||
| 0.35 - 0.43 | 0.40 - 0.65 | 0.10 - 0.35 | <0.025 | <0.025 | 1.4 - 1.8 | 0.15 - 0.25 | - | 0.9 - 1.3 | |
38HMJ - specifications and applications
Chrome-aluminium structural steel with addition of molybdenum and high hardenability intended for nitriding, achieving hardness after thermo-chemical treatment above 900 HV. The best mechanical properties after machining are achieved in cross-sections of up to approx. 80 mm.
38HMJ is used to manufacture parts or components that require surface sliding properties, high core hardness, heat resistance, relaxation, and corrosion.
The steel is used in the automotive and machine industries for diesel engine fuel pump parts, camshafts and crankshafts, cylinders, bushings, valve plates, moulds for pressing plastics, crankpins, grinding and milling spindles, piston rods, valve parts in superheated steam operation, e.g. flanges, gear wheels, pushers, bushings and cylinders of pneumatic machines.
The steel is not weldable, brittle and has limited impact resistance. The predecessor of 38HMJ steel grade was the 38HJ grade, which did not contain molybdenum in its chemical composition. The introduction of molybdenum has improved hardenability and resistance against tempering brittleness.
Mechanical properties of 41CrAlMo7-10, 1.8509 according to EN 10085
- Annealed condition +A - Hardness: <248 HB
- Heat-treated condition +QT:
- dimensions 16 - 40mm:
- Tensile strength, Rm: 950 - 1150 MPa
- Yield strength, Rp0,2: >750 MPa
- Elongation, A: >11%
- Impact resistance, KV: >25J
- dimensions 40 - 100mm:
- Tensile strength, Rm: 900 - 1100 MPa
- Yield strength, Rp0,2: >720 MPa
- Elongation, A: >13%
- Impact resistance, KV: >25J
- dimensions 100 - 160mm:
- Tensile strength, Rm: 850 - 1050 MPa
- Yield strength, Rp0,2: >670 MPa
- Elongation, A: >14%
- Impact resistance, KV: >30J
- dimensions 160 - 250mm:
- Tensile strength, Rm: 800 - 1000 MPa
- Yield strength, Rp0,2: >625 MPa
- Elongation, A: >15%
- Impact resistance, KV: >30J
- dimensions 16 - 40mm:
- Surface hardness after nitriding - HV1: 950
Mechanical properties of 34CrAlMo5-10, 1.8507 according to EN 10085
- Annealed condition +A - Hardness: <248 HB
- Heat-treated condition +QT - dimensions 16 - 70mm
- Tensile strength, Rm: 800 - 1000 MPa
- Yield strength, Re: >600 MPa
- Elongation, A: >14%
- Impact resistance, KV: >35J
- Surface hardness after nitriding - HV1: 950
Mechanical properties of 38HMJ according to PN-89/H-84030/03
- Hardness in softened condition +M: <229 HB
- Heat-treated condition +T:
- Tensile strength, Rm: >980 MPa
- Yield strength, Rp0,2: >830 MPa
- Elongation, A: >14%
- Necking, Z: >50%
- Impact energy, KU2: >72J
- Surface hardness after nitriding - HV: >900
Heat treatment processes:
- 38HMJ
- Softening annealing at 700 - 730℃
- Carburizing at 900 - 940℃
- Hardening in water or oil at 880 - 940℃
- Tempering at 570 - 650℃
- Nitriding at 500 - 520℃
- 41CrAlMo7-10, 1.8509
- Softening annealing at 650 - 700℃
- Hardening in water or oil at 870 - 930℃
- Tempering at 580 - 700℃
- Nitriding at 480 - 570℃
- 34CrAlMo5-10, 1.8507
- Softening annealing at 650 - 750℃
- Hardening in water or oil at 870 - 930℃
- Tempering at 580 - 700℃
- Nitriding at 480 - 570℃
In the above mentioned grades the company provides:
- Hot-rolled bars 38HMJ, 34CrAlMo5, 1.8507, 41CrAlMo7, 1.8509
- Forgings, rings and forged bars 38HMJ, 34CrAlMo5, 41CrAlMo7
Other designations, replacements for the grades:
38CrMoAl, CSN 15340, SS 2940, SACM 645, 41 CrAlMo 7, 41 CrAlMo 7-10, 34 CrAlMo 5, 34 CrAlMo 5-10, 34CrAlMo7-10, 41CrAlMo7-4, 905 M 39, 905M39, 1.8509, 1.8507, 38Kh2MUA, 38Kh2MJuA, 38H2MUA, 38H2MJuA, 38Ch2MUA, 38Ch2MJuA, 38Х2МЮА, 41-A, 35CrAl6, 34CrAlMo54, 38MoCrAl09X, 40CAD612, 41CrAlMo74, 40Cr7Al10Mo2, F-174, 38HJ.