iglidur® AB – material data

Diagram 02: Recommended maximum surface pressure as a function of temperature (60 MPa at +20 °C)
 
X = Temperature [°C]
Y = Load [MPa]

Diagram 03: Deformation under pressure load and temperatures
 
X = Load [MPa]
Y = Deformation [%]

Mechanical properties

With increasing temperatures, the compressive strength of iglidur® AB plain bearings decreases. The recommended maximum surface pressure is a mechanical material parameter. No con­clusions regarding the tribological properties can be drawn from this.

 

 

 
Diagram 03 shows the elastic deformation of iglidur® AB at radial loads. A possible deformation could be, among others, dependant on the duty cycle of the load.

Maximum running speed

m/s	Rotating	Oscillating	Linear
Continuous	0,7	0,5	1,0
Short-term	1,0	0,7	1,8

Table 03: Maximum surface speeds

Permissible surface speeds

iglidur® AB is mainly suitable for low speeds in dry running, but the specified values shown in table 03 can only be achieved at low pressures. At the given speeds, friction can cause a temperature increase to maximum permissible levels. In practice, though, this temperature level is rarely reached due to varying application conditions.

Temperatures

The temperatures prevailing in the bearing system also have an influence on the bearing wear. With increasing temperatures, the wear increases and this effect is significant when temperatures rise over +60 °C. At temperatures over +50 °C an additional securing is required.

iglidur® AB	Dry	Greases	Oil	Water
C. o. f. µ	0,11 - 0,21	0,09	0,04	0,04

Table 04: Coefficient of friction against steel (Ra = 1 μm, 50 HRC)

Friction and wear

Coefficient of friction and wear resistance are dependent on the application parameters (diagrams 04 and 05).

Diagram 06: Wear with various shaft materials, p = 1 MPa, v = 0.3 m/s
 
X = Shaft material
Y = Wear [μm/km]
 
A = Aluminium, hard-anodised
B = Automatic screw steel
C = Cf53
D = Cf53, hard-chromed
E = HR carbon steel
F = 304 stainless steel
G = High grade steel

Shaft materials

The friction and wear are also dependent, to a large degree, on the shaft material. Shafts that are too smooth, increase both the coefficient of friction and the wear of the bearing. Diagram 06 shows a summary of the results of tests with different shaft materials. When rotating at a load of 1 MPa, the wear on all tested shafts is very similar. Only the hard-anodised aluminium shafts cause a noticeable increase in the wear. As illustrated in diagram 07, the wear rate from pivoting and rotating movements at loads in increasing levels is also quite similar if the remaining parameters are identical.

Medium	Resistance
Alcohol	+ to 0
Hydrocarbons	+
Greases, oils without additives	+
Fuels	+
Diluted acids	0 to -
Strong acids	-
Diluted alkalines	+
Strong alkalines	0

+ resistant      0 limited resistance      – not resistant
All information given at room temperature [+20 °C] Table 05: Chemical resistance of iglidur® W300

Electrical properties

Specific contact resistance	> 1013 Ω cm
Surface resistance	> 1012 Ω

Radiation resistance

Plain bearings made from iglidur® AB are resistant to radiation up to an intensity of 3 · 102 Gy.

UV resistance

iglidur® AB bearings change colour under the influence of UV rays. However, hardness, compressive strength and the wear resistance of the material do not change.

Vacuum

In vacuum applications, any absorbed moisture content is outgassed. Use in a vacuum environment is only possible with dehumidified bearings.

Maximum moisture absorption

At +23 °C/50 % r.h.	0,2 % weight
Max. water absorption	0,4 % weight

Table 06: Moisture absorption

Diagram 10: Effect of moisture absorption
 
X = Moisture absorption [weight %]
Y = Reduction of inside diameter [%]

Moisture absorption

The humidity absorption of iglidur® AB bearings amounts to about 0.8  % weight in standard climatic conditions. The saturation limit submerged in water is 1.6 % weight.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® AB E10 [mm]	Housing H7 [mm]
to 3	0 - 0,025	+0,014 +0,054	0 +0,010
> 3 bis 6	0 - 0,030	+0,020 +0,068	0 +0,012
> 6 bis 10	0 - 0,036	+0,025 +0,083	0 +0,015
> 10 bis 18	0 - 0,043	+0,032 +0,102	0 +0,018
> 18 bis 30	0 - 0,052	+0,040 +0,124	0 +0,021
> 30 bis 50	0 - 0,062	+0,050 +0,150	0 +0,025
> 50 bis 80	0 - 0,074	+0,060 +0,180	0 +0,030

Table 07: Important tolerances for plain bearings according to ISO 3547-1 after being pressed in

Installation tolerances

iglidur® AB plain bearings are standard bearings for shafts with h-tolerance (recommended minimum h9). The bearings are designed for pressfit into a housing machined to a H7 tolerance. After being assembled into a nominal size housing, the inner diameter automatically adjusts to the E10 tolerances. In relation to the installation tolerance, the inner diameter changes with the absorption of humidity. For particular dimensions the tolerance differs depending on the wall thickness (please see product range table).