iglidur® A180 - Material data

Materials table

General features Unit iglidur® A180 test method
Density g/cm³ 1,46
Colour white
Max. humidity absorption at 23°C/50% R. H. % weight 0,2 DIN 53495
Max. water absorption % weight 1,3
Coefficient of surface friction, dynamic, against steel µ 0,05 - 0,23
PV values max. (dry) MPa x m/s 0,31

Mechanical properties
Bending E-module MPa 2.300 DIN 53457
Tensile strength at +20 °C MPa 88 DIN 53452
compressive strength MPa 78
Maximum recommended surface pressure (20° C) MPa 28
Shore D hardness 76 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 > 1012 DIN IEC 93
Surface resistance Ω > 1011 DIN 53482
'Table 01: Material Data

Fig. 01: Permissible pv values for iglidur® A180 plain bearings


Figure 01: Permitted PV values for iglidur® A180 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]

 
Bearings made of iglidur® A180 are suitable for application in direct contact with foodstuffs. Hence they are the ideal solution for bearing positions on machines for the food and packaging industries, the medical equipment manufacturing, for small equipment for households, etc. The iglidur® A180 distinguishes itself also in wet cleaning or where process-dependent contact with wet media is the business of the day by its extremely low humidity absorption

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.

m/s Rotary oscillating Linear
Constant 0,8 0,6 3,5
Short-term 1,2 1 5
Table 02: Maximum surface speeds

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. The values specified in Table 02 state the limits to which the long-term permitted temperature rises due to friction heat. In practice these limit values are not always reached due to interactions.

iglidur® A180 Operating temperature
Lower - 50 °C
Upper, long-term + 90 °C
Upper, short-term + 110 °C
Secure axially in addition + 60 °C
Table 03: Temperature limits for iglidur® A180

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 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

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).
iglidur® A180 Dry Grease Oil Water
Coefficients of friction µ 0,05 - 0,23 0,09 0,04 0,04
Table 04: Coefficients of friction for iglidur® A180 against steel (Ra = 1 µm, 50 HRC)

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

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).
Fig. 07: Wear in oscillating and rotating Fig. 07: Wear in oscillating and rotating applications with Cf53 dependent on the load
 
X = Load [MPa]
Y = Wear [μm/km]
 
A= rotary
B= oscillating

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
iglidur® A180 bearings are electrically insulating.

Chemical resistance

iglidur® A180 bearings can be used under various environmental conditions and in contact with numerous chemicals. Table 05 gives an overview of the chemical resistance of iglidur® A180 bearings at room temperature.

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
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 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%.

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). 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.