AISI 440C STAINLESS STEEL BALLS

Martensitic hardened stainless steel balls, they feature remarkable hardness, wear resistance, surface finishing, narrow dimensional tolerances.
For that reason this type of steel is frequently used in precision devices. Balls are provided in the passivated condition.
Applications
Precision bearings, anti-friction bearings, special valves, conveyor belts and rollers, ballpoint pens. They are used in foodstuff, medical instruments, quick couplings, recirculating ball bearings, knotting devices, oil refinery devices.
Chemical composition
%C
%Si
%Mn
%P
%S
%Cr
%Mo
-
-
-
-
-
0.95-1.20
1.00 max
1.00 max
0.040 max
0.030 max
16.00-18.00
0.75 max
-
-
-
-
-
International standards
ITA
USA
GER
FRA
UK
RUS
CHN
JAP
X 105CrMo17
440C
1.4125
Z100CD17
-
95X18
9Cr18Mo
SUS440C
Physical / mechanical / thermal / electric / magnetic properties
Property
Symbol
U.o.M.
Type
Notes
Values
Density
δ
[g/cm3]
Physical
Room temp.
7.70
Young's modulus
E
[GPa]
Mechanical
-
210
Specific heat
c
[J/kg-K]
Thermal
Room temp.
450
Coefficient of linear thermal expansion
α
[10^-6/ºC]
Thermal
(ΔT=0-100°C)
10.2
Thermal conductivity
λ
[W/(m·K)]
Thermal
Room temp.
19.6
Electric resistivity
ρ
[Ω*m*10^-9]
Electric
-
680
Relative magnetic permeability
µ
-
Magnetic
Not hardened
> 700
Technical data
Property
Type
U.o.M.
Values
U.o.M.
Values
Hardness
Mechanical
[HRC]
57 - 65
-
-
Ultimate tensile strength
Mechanical
[MPa]
1900 - 2000
[psix10^3]
275 - 290
Service temperature
Thermal
[ºC]
0 / 400
[ºF]
32 - 752
Range
Diameters (min/max)
U.o.M.
Diameters (min/max)
U.o.M.
Precision grades (ISO 3290-1 / DIN 5401 / AFBMA)
0.300 - 300.000
[mm]
1/64 - 12
["]
See section International Standards: ISO 3290-1 / DIN 5401 / AFBMA
Corrosion Resistance
The material resists to corrosion in contact with freshwater, steam, oil, petrol, alcohol. They are subjected to pitting corrosion in sea water environments. Poor corrosion resistance in acid environments.
Revision n.8