iglidur® D - Material data

Materials table

General features	Unit	iglidur® D	test method
Density	g/cm³	1,40
Colour		green
Max. humidity absorption at 23°C/50% R. H.	% weight	0,3	DIN 53495
Max. water absorption	% weight	1,1
Coefficient of surface friction, dynamic, against steel	µ	0,08 - 0,26
PV values max. (dry)	MPa x m/s	0,27
Mechanical properties
Bending E-module	MPa	2.000	DIN 53457
Tensile strength at +20 °C	MPa	72	DIN 53452
compressive strength	MPa	70
Maximum recommended surface pressure (20° C)	MPa	23
Shore D hardness		78	DIN 53505
Physical and thermal properties
Max. long term application temperature	°C	+90
Max. short term application temperature	°C	+110
Lower application temperature	°C	-50
Heat conductivity	W/m x K	0,25	ASTM C 177
Coefficient of thermal expansion (at 23° C)	K^-1 x 10^-5	11	DIN 53752
Electrical properties
Specific forward resistance	Ωcm	> 10¹⁴	DIN IEC 93
Surface resistance	Ω	> 10¹⁴	DIN 53482

'Table 01: Material Data

Fig. 01: Permissible pv values for iglidur® D plain bearings

Figure 01: Permitted PV values for iglidur® D 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]

The development of the iglidur® D as a plain bearing material placed high performances and very low cost high up on the application profile. In addition it should achieve low coefficients of friction in the dry operation especially at high speeds. The material containing silicon moreover achieves extremely low coefficients of friction in dry operation and runs largely free of stick-slip effects.

Figure 02: Maximum recommended surface pressure dependent on the temperature (23 MPa to +20 °C)

X = Temperature [°C]
Y = Load [MPa]

Figure 03: Deformation under load and temperatures

X = Load [MPa]
Y = Deformation [%]

Mechanical properties

Maximum recommended surface pressure represents a mechanical material parameter. Tribological conclusions cannot be drawn from it. With increasing temperatures, the compressive strength of iglidur® D plain bearings decreases. Fig. 02 clarifies this connection.

iglidur® D bearings were developed mainly for low to medium radial loads. Figure 03 shows the elastic deformation of iglidur® D with radial loads. The deformation amounts to about 3% at the maximum recommended surface pressure of 23 MPa. A plastic deformation can be negligible up to this value. It is however also dependent on the period of exposure.

m/s	Rotary	oscillating	Linear
Constant	1,5	1,1	8
Short-term	3	2,1	10

Table 02: Maximum surface speeds

Permitted surface speeds

iglidur® D bearings are suitable for high surface speeds. Speeds of up to 10 m/s are permitted in linear motions! Here too the specified maximum values can be achieved only with minimum pressure loads. The specified values show the speed at which an increase in temperature up to the long-term permitted value can occur due to friction.

Surface speed

p x v value and lubrication

iglidur® D	Application temperature
Lower	- 50 °C
Upper, long-term	+ 90 °C
Upper, short-term	+ 110 °C
Secure axially in addition	+ 50 °C

Table 03: Temperature limits

Temperatures

With increasing temperatures, the compressive strength of iglidur® D plain bearings decreases. Fig. 02 clarifies this connection. The temperatures prevailing in the bearing system also have an influence on the bearing wear. An additional securing is recommended at temperatures higher than +50°C.

Temperatures, coefficient of thermal expansion

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 = Coefficient of friction μ
Y = Load [MPa]

Friction and wear

The coefficient of friction declines like the wear resistance with increasing load. In the Ra range between 0.4 and 0.6 µm, the coefficient of friction attains its optimum value.

iglidur® D	Dry	Grease	Oil	Water
Coefficients of friction µ	0,08 - 0,26	0,09	0,04	0,04

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

Coefficients of friction

Wear resistance

Fig. 06: Wear, rotating application with various

Figure 06: Wear, rotating application with different 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 display a summary of the results of tests with different shaft materials conducted with bearings made of iglidur® D.

Please contact us in case the shaft material scheduled by you is not included in this list.

Figure 07: Wear in pivoting 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	+
Hydrocarbons	+
Greases, oils without additives	+
Fuels	+
Diluted acids	0 to -
Strong acids	-
Diluted bases	+
Strong bases	+ to 0

+ resistant 0 conditionally resistant - non-resistant

All specifications at room temperature[+20 °C]
Table 05: Chemical resistance of the iglidur® bearings D

Electrical properties

Specific forward resistance	> 10¹⁴ Ωcm
Surface resistance	> 10¹⁴ Ω

Chemical resistance

iglidur® D bearings are resistant to very weak acids, diluted alkalis as well as to fuels and all kinds of lubricants.

Radioactive rays

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

UV-resistant

iglidur® D bearings are resistant to UV radiation, but the tribological properties deteriorate with continuous exposure.

Vacuum

In vacuum, iglidur® D degases. The use in vacuum is possible only limitedly.

Electrical properties

iglidur® D bearings are electrically insulating.

Delivery program

The iglidur® D bearings are manufactured according to order specifications. Please contact us for applications with large numbers of bearings made of iglidur® D as alternative to iglidur® J.

Maximum moisture absorption
by +23 °C/50 % r. F.	0,3 weight-%
Max. water absorption	1,1 weight-%

Table 06: Humidity absorption of iglidur® D

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® J bearings amounts to about 0.3 Wt.-% in standard climatic conditions. The saturation limit in water is 1,1 %. This low humidity absorption also allows the use in wet environment.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® D E10 [mm]	Housing H7 [mm]
Up to 3	0 - 0,025	+0,014 +0,054	0 +0,010
> 3 to 6	0 - 0,030	+0,020 +0,068	0 +0,012
> 6 to 10	0 - 0,036	+0,025 +0,083	0 +0,015
> 10 to 18	0 - 0,043	+0,032 +0,102	0 +0,018
> 18 to 30	0 - 0,052	+0,040 +0,124	0 +0,021
> 30 to 50	0 - 0,062	+0,050 +0,150	0 +0,025
> 50 to 80	0 - 0,074	+0,060 +0,180	0 +0,030
> 80 to 120	0 - 0,087	+0,072 +0,212	0 +0,035
> 120 to 180	0 - 0,100	+0,085 +0,245	0 +0,040

Table 07: Important tolerances iaw. ISO 3547-1 after press-fitting.

Installation tolerances

iglidur® D- 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 E10 tolerance.