42MnMo7
42MnMo7 is a material in the category Heat-resistant structural steels, held under material number 1.5432. Its recorded composition includes C 0.38–0.45%, Si 0.2–0.35%, P 0.04%, Mn 1.55–1.85% and Mo 0.15–0.25%. We list one designation recorded for this grade, in the standard UNS. Its recorded density is 7.85 g/cm³.
If you came for one of these
The most-used names for this grade.About Heat-resistant structural steels
Heat-resistant structural steels are structural steels designed to retain useful strength and dimensional stability at elevated temperatures. They are used for load-bearing components in hot-service equipment where mechanical performance must be maintained during heating.
This describes the material class as a whole. Always confirm the individual grade against the standard before ordering.
Also known as
2 designations · 2 standards · nothing hidden- 42MnMo7This grade’s own name
Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here.
Chemical composition
6 elements on file · weight %What this alloy is
Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade.
| Element | % by weight |
|---|---|
0.38–0.45 — | |
0.2–0.35 | |
1.55–1.85 — | |
0.04 | |
0.04 | |
0.15–0.25 |
The scale is logarithmic, not the element’s raw share of the alloy — the only honest way to fit 0.01 % and 100 % in one picture, and it means every value here can be compared with every other.
| Element | As publishedsource text, verbatim | Min% by weight | Max% by weight | Bound |
|---|---|---|---|---|
| C | 0,38-0,45 | 0.380 | 0.450 | Range |
| Si | 0,20-0,35 | 0.200 | 0.350 | Range |
| P | 0,04 | 0.040 | 0.040 | Exact |
| S | 0,04 | 0.040 | 0.040 | Exact |
| Mn | 1,55-1,85 | 1.550 | 1.850 | Range |
| Mo | 0,15-0,25 | 0.150 | 0.250 | Range |
The published column is the source string byte-for-byte, decimal comma and all; Min and Max are the parsed bounds. Elements not listed have no value on file — they are omitted, never inferred.
Predicted transformation temperatures
Not enough recorded composition to predict a transformation temperature for this grade — missing: Ni, Cr.
Physical & mechanical properties
An absent property means we hold no value for it — it is left out rather than estimated, interpolated from a neighbouring grade, or filled from a handbook. It does not mean the property is undefined for the material.
Similar grades — and why
Selection rule, stated so you can disagree with it: same number class 1.5, a shared category, and a published range for Mn / Si that overlaps this grade’s. These are neighbours in composition space — they are not equivalents, and none is claimed to be interchangeable with this grade.
Mn 1,50-1,80 · Si ≤0,60
- ΔMn 0.05
- ΔSi 0.02
- 2 designations
Mn 1,50-1,80 · Si ≤0,60
- ΔMn 0.05
- ΔSi 0.02
- 1 designations
Mn 1,20-1,80 · Si ≤0,60
- ΔMn 0.20
- ΔSi 0.02
- 1 designations
Mn 1,40-1,70 · Si 0,20-0,50
- ΔMn 0.15
- ΔSi 0.07
- 8 designations
Mn 1,35-1,65 · Si 0,08-0,22
- ΔMn 0.20
- ΔSi 0.13
- 2 designations
Mn 1,80-2,20 · Si 0,08-0,22
- ΔMn 0.30
- ΔSi 0.13
- 3 designations
Looking for this grade under another name?
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