38CrMoAl Alloy Structure Steel (Nitride Steel) Round Bar DIN 1.8509
41CrAlMo7-10 Forged Steel Rod
38CrMoAl is an alloy structural steel characterized by high
aluminum composition, which is generally used after quenching and
nitriding.After nitriding, 38CrMoAl has high surface hardness, wear
resistance and fatigue strength, and has good heat resistance and
corrosion.
The characteristic of 38CrMoAl nitriding is that the speed is fast
and the depth of nitriding layer can be obtained. However, the
brittleness of the nitriding layer is relatively large, so it is
not suitable for making parts that bear great impact.
CHEMICAL COMPOSITION(%)
| STANDARD | GB/T 3077 | SAE 6470 | JIS G4053 | DIN EN 10085 |
| GRADE | 38CrMoAl | 135 Mod UNS K24065 | SACM645 (SACM1) | 1.8509 41CrAlMo7-10 |
| C | 0.35~0.42 | 0.38~0.43 | 0.40~0.50 | 0.38~0.45 |
| Si | 0.20~0.45 | 0.20~0.40 | 0.15~0.50 | ≤0.40 |
| Mn | 0.30~0.60 | 0.50~0.80 | ≤0.60 | 0.40~0.70 |
| P | ≤0.035 | ≤0.025 | ≤0.030 | ≤0.025 |
| S | ≤0.035 | ≤0.025 | ≤0.030 | ≤0.035 |
| Cr | 1.35~1.65 | 1.40~1.80 | 1.30~1.70 | 1.50~1.80 |
| Mo | 0.15~0.25 | 0.30~0.40 | 0.15~0.35 | 0.20~0.35 |
| Al | 0.70~1.10 | 0.95~1.30 | 0.70~1.20 | 0.80~1.20 |
HEAT TREATMENT
| TYPES | TEM ℃ | COOLING | HRC |
| ANNEALING | 840~870 | FURNACE COOLING | ≤229HB |
| NORMALIZING | 930~970 | AIR COOLING | — |
| QUENCHING | 940 | OIL | ＞56 |
| TEMPERING | 150~200 | WATER OR OIL | 51~56 |
| 300~400 | WATER OR OIL | 45~51 |
| 500~550 | WATER OR OIL | 35~39 |
| 600~650 | WATER OR OIL | 28~31 |
TRIDING TREATMENT
The process flow of nitriding parts is generally: forging →
normalizing (annealing) → rough machining → tempering and tempering
→ finishing machining → de-stress → fine grinding → nitriding →
fine grinding → assembly.
The purpose of 38CrMoAl nitriding treatment is mainly for wear
resistance.After nitriding, its hardness is as high as HV800, the
hardened layer can reach 0.30mm ~ 0.5mm.
APPLICATION
38CrMoAl is mainly used in the manufacture of parts with precise
size, requiring high wear resistance and fatigue strength, and not
subjected to large impact load, such as cylinder liner, bottom
sleeve, gear, bolts, shaft and rotor, etc.
In addition, because Al and Cr elements can form a dense
passivation film on the surface of steel, so 38CrMoAl is also a
kind of seawater corrosion resistant steel.Its seamless steel pipe
is the most ideal pipeline and processing material for transporting
water, oil and gas and seawater containing medium in coastal power
plants, coastal oil fields, coastal natural gas and petrochemical
plants.
