iglidur® A180 - Material data

Figure 02: Maximum recommended surface pressure dependent on the temperature (20 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. With increasing temperatures, the compressive strength of iglidur® A180 bearings decreases. Fig. 02 clarifies this connection.
 
Figure 03 shows the elastic deformation of iglidur® A180 with radial loads. Under the maximum recommended surface pressure of 20 MPa, the deformation amounts to less than 2.5%. A plastic deformation is negligible up to this radial load. It is however also dependent on the period of exposure.

Maximum surface speed

m/s	Rotating	Oscillating	Linear
Constant	0,8	0,6	3,5
Short-term	1,2	1	5

Permitted surface speeds

iglidur® A180 is developed for low surface speeds. Maximum speeds up to 0.8 m/s (rotating) and 3.5 m/s (linear) respectively are permitted for continuous application in dry operation. These specified values state the limits to which the long-term permitted temperature rises due to frictional heat. In practice these limit values are not always reached due to interactions.

Figure 7.3: Maximum recommended surface pressure dependent on the temperature

Temperatures

The upper short-term application temperature is +110℃. With increasing temperatures, the compressive strength of iglidur® A180 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 +60°C.
 

Figure 2.4: Coefficients of friction dependent on the surface speed, p = 0.75 MPa

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

Coefficient of friction and wear resistance alter with the application parameters. With increasing load, the coefficient of friction however sinks markedly (Fig. 04 and 05).

Coefficients of friction for iglidur® A180 against steel
(Ra = 1 µm, 50 HRC)

iglidur® A180	Dry	Fat	Oil	Water
Coefficients of friction µ	0,05 - 0,23	0,09	0,04	0,04

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

The Fig. 06 displays the results of tests with different shaft materials conducted with plain bearings made of iglidur® A180. The combination "iglidur® A180/hard anodized aluminum" clearly stands out. It attains good to excellent wear rates also with other shafts. With Cf53 shafts, the higher wear in swivelling applications is exemplary compared to rotating applications (Fig. 07).

Medium	Resistance
Alcohols	+
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 iglidur® A180

Electrical properties

Specific forward resistance	> 1012 Ωcm
Surface resistance	> 1011 Ω

Chemical resistance

iglidur® A180 bearings can be used under various environmental conditions and in contact with numerous chemicals. Table 7.6 gives an overview of the chemical resistance of iglidur® A180 bearings at room temperature.

The iglidur® A180 bearings are not chemically altered by humidity absorption. However alteration of the features can occur according to water content. The iglidur® A180 bearings absorb up to 0.2% water through atmospheric humidity (23° C, 50% relative atmospheric humidity).

Radioactive rays

iglidur® A180 bearings are radiation resistant up to a radioactive intensity of 3 x 10² Gy. Higher radiations affect the material and can lead to the loss of important mechanical properties.

UV-resistant

iglidur® A180 bearings are resistant to UV radiation, but the tribological properties deteriorate with continuous exposure.

Vacuum

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

Maximum moisture absorption
by +23 °C/50 % r. F.	0,2 weight-%
Max. water absorption	1,3 weight-%

Table 06: Humidity absorption of iglidur® A180

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

humidity absorption / moisture absorption

The iglidur® A180 bearings absorb up to 0.2% water through atmospheric humidity (+23°C, 50% relative atmospheric humidity), when saturated with water they absorb 1.3%.

Important tolerances for iglidur® A180 bearings according to ISO 3547-1 after the press-fit.

Diameter d1 [mm]	Shaft h9 [mm]	iglidur® A180 F10 [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

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

Installation tolerances

iglidur® A180 bearings are standard bearings for shafts with h-tolerance (recommended minimum h9).

After the installation in a housing bore with H7 tolerance, the inner diameter of the bearing automatically adjusts to the E10 tolerance.