Steel 60Г17ХН2Ф (MML-2)

Designation

Name The value
Designation GOST Cyrillic 60Г17ХН2Ф
Designation GOST Latin 60G17XH2F
Transliteration 60G17HN2F
By chemical elements 60Mn17CrН2V
Name The value
Designation GOST Cyrillic ММЛ-2
Designation GOST Latin MML-2
Transliteration MML-2
By chemical elements MoMoBe-2

Description

60Г17ХН2Ф steel is used: for the manufacture of castings by sand casting parts, buildings, machinery and equipment of the Navy ships of all classes, types and appointments, as well as ballast, which is required of namagnichennosti μ≤ 1,262·10-6 G/m (1,005 GS/e) group I (ballasts, keys, on-Board mooring fairleads, etc.), group II (mortars, bearing housings of the spindles, the hubs of rudder blades, covers, housings, levers, sprockets windlasses, the plates and drums are the base of the spires, etc.) and group III (propeller shaft brackets, stem, glasses of end and intermediate brackets, post rudder, spinners, anchors, mortars, etc.).

Note

Vysokoorganizovannaja low austenitic steel.
Difficult the production of thin-walled complicated castings because of the tendency of steel to the formation of oxide captivity.
Magnetic permeability μ ≤ 1,005 GS/e and is almost constant in any thermal and thermomechanical processing. The magnetic field of the casting is increased in the presence of penetration and in particular the ferromagnetic oxides.
Do not use steel grades for cast metal parts, running on friction (bushings, worm wheels, gear) or requiring surface hardening by nitriding, as well as parts of valves and similar parts. Unacceptable use of steel for the manufacture of parts without cathodic protection, operating in seawater and other environments that cause intense General corrosion.
Steel has low frictional properties and surface hardening (nitriding and carburizing) is not exposed.
Steel is not prone to intergranular corrosion and acquires a tendency only after a long vacation at a temperature of 650−700° C and this is due to the precipitation of carbides along the grain boundaries of austenite. Steel is prone to General corrosion. Therefore, it is recommended to use protectors in conjunction with paint coatings.

Standards

Name Code Standards
Castings, non-ferrous metals and alloys В84 OST 9261-76, RD 9257-76

Chemical composition

Standard C S P Mn Cr Si Ni Fe V
OST 9261-76 0.55-0.63 ≤0.025 ≤0.025 16-18 1.6-1.9 0.6-1 2-2.5 Rest 0.5-0.8
RD 9257-76 0.55-0.63 ≤0.025 ≤0.025 16-18 1.6-1.9 0.6-1 2-2.5 Rest 0.5-0.8
Fe is the basis.
According to OST 9261-76, when steel is smelted for ballast production, it is allowed to increase the carbon content to 0.75% and manganese to 19.0%, and to reduce the nickel content to zero.

Mechanical properties

sT|s0,2, MPa σU, MPa d5, % KCU, kJ/m2
Casting as supplied. Without heat treatment (thickness of wall up to 20 mm) or normalizing at 1100 °C (wall thickness > 20 mm)
≥343 ≥490.5 ≥14 ≥980

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture
KCU Toughness

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) R, Mr. · m a, 10-6 1/°C С, J/(kg · °C)
20 1896 7800 - 750 - 473
100 - - 1633 - 1585 -
200 - - 1884 - 1948 -
300 - - 2093 - 2037 -
400 - - 2345 - 2120 -
500 - - 2596 - 2180 -
600 - - 2428 - 2225 -
700 - - - - 2277 -
800 - - - - 2280 -
900 - - - - 2450 -
1000 - - - - 2471 -

A description of the physical symbols

Name Description
r Density
l Coefficient of thermal conductivity
R UD. the resistivity

Technological properties

Name The value
Weldability good weldability. The castings are subjected to welding, as between themselves, and with low sheet steel and other structural steels. It is also possible welding defects.
Machinability reduced workability is close in parameters to the machinability of steel 45Г17Ю3 (Yu3).