Cast iron ЧМ1,8
Designation
| Name |
The value |
| Designation GOST Cyrillic |
ЧМ1,8 |
| Designation GOST Latin |
ChM1,8 |
| Transliteration |
ChM18 |
| The chemical elements |
ZrMo1,8 |
Description
Cast iron ЧМ1,8 is used: for the production of castings for aircraft.
Standards
| Name |
Code |
Standards |
| Castings with special properties (cast iron and steel) |
В83 |
OST 1 90077-72 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Fe |
Cu |
| OST 1 90077-72 |
2.8-3.6 |
≤0.1 |
≤0.3 |
0.6-1.2 |
0.2-0.4 |
1.3-1.9 |
The rest |
1.5-2 |
Fe is the basis.
According to OST 1 90077-72, with the following mechanical properties and microstructure satisfactory, the following deviations in chemical composition are acceptable: for carbon ± 0.10%, for chromium, silicon, molybdenum, nickel and copper + 0.2% for each.
Mechanical characteristics
| Brinell hardness number, MPa |
| Castings on OST 1 90077-72 |
| 207-262 |
Technological properties
| Name |
The value |
| Macrostructure and contamination |
The appearance of the fracture of castings on OST 1 90077-72 should be dense, fine-grained, light-gray, with no signs of chill. Surface of castings shall be cleaned of sand and metal penetration. Sprues, heaving, bays, growths and veining must be cut or polished by abrasive material in the tolerances on the drawing. Nikitina, crack and end-to-end sinks are not allowed. |
| Microstructure |
According to OST 1 90077-72 microstructure of castings shall consist of lamellar pearlite and sarbatoarea, phosphides in the form of sharp inclusions of lamellar graphite and twists medium size of ferrite in the field of vision is not more than 10% of the eutectic graphite is not more than 10%. |
| Features of heat treatment |
According to OST 1 90077-72 castings are supplied without heat treatment. |
