iglidur® F - Material data

Materials table

General features Unit iglidur® F test method
Density g/cm³ 1,25
Colour black
Max. humidity absorption at 23°C/50% R. H. % weight 1,8 DIN 53495
Max. water absorption % weight 8,4
Coefficient of surface friction, dynamic, against steel µ 0,1 - 0,39
PV values max. (dry) MPa x m/s 0,34

Mechanical properties
Bending E-module MPa 11.600 DIN 53457
Tensile strength at +20 °C MPa 260 DIN 53452
compressive strength MPa 98
Maximum recommended surface pressure (20° C) MPa 105
Shore D hardness 84 DIN 53505

Physical and thermal properties
Max. long term application temperature °C +140
Max. short term application temperature °C +180
Lower application temperature °C -40
Heat conductivity [W/m x K] 0,65 ASTM C 177
Coefficient of thermal expansion (at 23° C) [K-1 x 10-5] 12 DIN 53752

Electrical properties
Specific forward resistance Ωcm < 103 DIN IEC 93
Surface resistance Ω < 102 DIN 53482
'Table 01: Material Data




Figure 01: Permitted PV values for iglidur® F bearings with 1 mm wall thickness in dry operation against a steel shaft, at 20°C, installed in a steel housing.

X = Surface speed [m/s]
Y = Load [MPa]

 
When bearings need to be electrically conductive, especially in applications that should keep out static, the iglidur® F is the right choice. Moreover, the iglidur® F bearings are extremely pressure resistant. At room temperature, they could be statically loaded up to 100 MPa.

Figure 02: Maximum recommended surface pressure dependent on the temperature (105 MPa to +20 °C)
 
X = Temperature [°C]
Y = Load [MPa]
Figure 03: Deformation under load and temperatures

X = Load [MPa]
Y = Deformation [m/s]

Mechanical properties

Maximum recommended surface pressure represents a mechanical material parameter. Tribological conclusions cannot be drawn from it. The pressure resistance of iglidur® F plain bearings declines with increasing temperatures. Fig. 02 clarifies this connection. With the long-term permitted application temperature of +140°C, the permitted surface pressure still amounts to 50 MPa.
 
Diagram 03 shows the elastic deformation of iglidur® F during radial loading. Under the maximum recommended surface pressure of 105 MPa, the deformation amounts to less than 3,0%. A plastic deformation can be negligible up to this pressure load. It is however also dependent on the period of exposure.

Maximum surface speed

m/s Rotary oscillating Linear
Constant 0,8 0,6 3
Short-term 1,5 1,1 6
Table 02: Maximum surface speeds

Permitted surface speeds

The maximum permitted surface speeds are based on the operation period and the type of motion. A bearing is the most stressed in long-term rotating motions. Here the maximum speed for the iglidur® F bearing is 0.8 m/s. The maximum values specified in Table 02 are attained only at minimum pressure loads. In practice these limit values are not often attained due to interactions.

iglidur® F Application temperature
Lower - 40 °C
Upper, long-term + 140 °C
Upper, short-term + 180 °C
Secure axially in addition + 105 °C
Table 03: Temperature limits for iglidur® F

Temperatures

The ambient temperatures strongly influence the properties of bearings. The pressure resistance of iglidur® F bearings declines with increasing temperatures. The wear also increases. Additional safety is required at temperatures over +105°C.

Figure 04: Coefficients of friction dependent on the surface speed, p = 0,75 MPa

X = Surface speed [m/s]
Y = Coefficient of friction μ
Figure 05: Coefficients of friction dependent on the load, v = 0,01 m/s

X = Load [MPa]
Y = Coefficient of friction μ

Friction and wear

The coefficients of friction in the dry operation are not so favorable in iglidur® F bearings like in many other iglidur® materials. However iglidur® bearings can be lubricated without any problems, and iglidur® F bearings attain excellent results compared among the lubricated iglidur® bearings.
iglidur® F dry Grease Oil Water
Coefficients of friction µ 0,1 - 0,39 0,09 0,04 0,04

Table 04: Coefficients of friction for iglidur® G against steel (Ra = 1 μm, 50 HRC)

Wear, rotating application with various shaft materials Fig. 06: Wear, rotating application with various shaft materials p = 1 MPa, v = 0.3 m/s
 
X = shaft materials
Y = wear [μm/km]
 
A = Aluminum, hard-anodized
B = machining steel
C = Cf53
D = Cf53, hard chrome-plated
E = St37
F = V2A
G = X90

Shaft materials

Figures 06 and 07 show an excerpt of the results of tests with different shaft materials conducted with bearings made of iglidur® F. In the lowest load range, the hard-chromed shafts prove to be the most suitable counter partner in rotating applications with iglidur® F bearings.
Wear in oscillating and rotating Fig. 07: Wear in oscillating and rotating applications with various shaft materials, p = 2 MPa
 
Y = wear [μm/km]
 
A= Cf53
B= hard chrome-plated
C= V2A
D= St37
 
blue= rotating
pink= oscillating

Medium Resistance
Alcohols + to 0
Hydrocarbons +
Greases, oils without additives +
Fuels +
Diluted acids 0 to -
Strong acids -
Diluted bases +
Strong bases + to 0
+ resistant      0 limited resistance      - not resistant
All specifications at room temperature[+20 °C]
Table 05: Chemical resistance of the iglidur® bearings F


Electrical properties

Specific forward resistance < 103 Ωcm
Surface resistance < 102 Ω

Chemical resistance

iglidur® F bearings have a good resistance against chemicals. The particularly high resistance to lubricants is to be highlighted, even at high temperatures (around +120°C). Hence the iglidur® F bearings are particularly suitable for applications that call for lubrication necessitated by other parts. The iglidur® F is not affected by most weak organic and inorganic acids.

Radioactive rays

iglidur® F bearings are radiation resistant up to a radiation intensity of 3 x 102 Gy.

UV-resistant

iglidur® F bearings are permanently resistant against UV rays.

Vacuum

In application in vacuum, the potentially existent moisture content is degassed. For this reason only the dry iglidur® F bearings are suitable for vacuum.

Electrical properties

iglidur® F bearings are electrically conductive..

Maximum moisture absorption
by +23 °C/50 % r. F. 1,8 weight-%
Max. water absorption 8,4 weight-%
Table 06: Moisture absorption of iglidur® F
Effect of moisture absorption on plain bearings Diagram 10: Effect of moisture absorption
 
X = Moisture absorption [weight %]
Y = Reduction of inside diameter [%]

humidity absorption / moisture absorption

The humidity absorption of iglidur® 200 bearings amounts to about 1,8% in standard climatic conditions. The saturation limit in water is 8,4 %. This should be considered according to application conditions.

Diameter
d1 [mm]
Shaft h9
[mm]
iglidur® F
D11 [mm]
Housing H7
[mm]
Up to 3 0 - 0,025 +0,020 +0,080 0 +0,010
> 3 to 6 0 - 0,030 +0,030 +0,105 0 +0,012
> 6 to 10 0 - 0,036 +0,040 +0,130 0 +0,015
> 10 to 18 0 - 0,043 +0,050 +0,160 0 +0,018
> 18 to 30 0 - 0,052 +0,065 +0,195 0 +0,021
> 30 to 50 0 - 0,062 +0,080 +0,240 0 +0,025
> 50 to 80 0 - 0,074 +0,100 +0,290 0 +0,030

Table 07: Important tolerances for iglidur® F bearings according to ISO 3547-1 after the press-fit.

Installation tolerances

iglidur® F bearings are standard bearings for shafts with h-tolerance (recommended minimum h9). The bearings are designed for press-fit in a housing with h7 tolerance. After the installation in a housing with nominal diameter, the inner diameter of the bearing automatically adjusts to the D11 tolerance. On certain dimensions, the tolerance varies from this as a function of the wall-thickness (see product range).