Nylon CF Slide has been compared to 9 other materials to search for the best candidate to replace POM components with a PFAS free material. Specific focus was put in wear and friction coefficients against steel and stainless steel.
Test description
Two types of test being performed
Bearing test (wear rotating, this is a tough test on any material)
Taber test (wear rotating) H-10 abrasive wheel (intermediate abrasiveness) 1000 revolutions, assessment every 100 revolutions. 1kg load
Measurement outcomes
Bearing: Wear + friction against two steel types (Cf53 and V2A) and two time intervals (2h and 8h)
Taber: wear (material loss) after maximum 10 points
Test results
Bearing tests
The material experienced a low coefficient of friction (measured at 1 MPa, rotations 0.3 m/s, after 2 and 8 hours against Cf53 (steel) and V2A (Stainless Steel): all between 0,18 and 0,26. Our requirement was similar friction as POM (<0.3) and only 4 out of 10 materials accomplished this of which 2 PFAS containing commercial materials.
The wear resistance was good. It survived in rotation for 8 hours at 0.3 m/s, 1 MPa against Cf53 (steel) and V2A (Stainless Steel), and unlike many other materials (with lower HDT) the wear was same against steel and stainless steel (13,3 um/km). The prints even survived for 48 hours against stainless steel. No other material except for PFAS containing samples survived this.
Taber test
Also in the Taber test, Nylon CF Slide showed the least wear after PFAS containing commercial materials. H-10 abrasive wheel (intermediate abrasiveness), 1000 revolutions, assessment every 100 revolutions and 1kg load was applied. Weight loss was less than 0,05 gram.
Test details
Bearing results – Nylon CF Slide detailed and long term results
Rotation
Shaft
p in MPa
v in m/s
rpm
temperature in °C
duration in min
Inside diameter before [mm]
Inside diameter after [mm]
Wear rate µm/km
Nylon CF Slide
Cf53
1
0,3
573
23
4830
10,30
10,80
5,75
Nylon CF Slide
Cf53
1
0,3
573
23
5820
10,30
10,76
4,39
Nylon CF Slide
V2A
1
0,3
573
23
5820
10,33
10,83
4,77
Nylon CF Slide
V2A
1
0,3
573
23
2135
10,36
10,65
7,55
Linear
Bearing
Shaft
p [MPa]
speed [rpm]
v [m/s] with 5mm stroke length
Time [h]
Inside diameter before [mm]
Inside diameter after [mm]
Wear rate [µm/km]
Nylon CF Slide
Cf53
1
600
0,1
77,75
10,50
10,77
9,646
Nylon CF Slide
Cf53
1
600
0,1
77,75
10,56
10,78
7,860
Nylon CF Slide
V2A
1
600
0,1
48
10,50
10,88
21,991
Nylon CF Slide
V2A
1
600
0,1
48
10,54
10,90
20,833
Summary
Wear rate [µm/km]
Friction 1 MPa
Oscillating 60°; 0,01 m/s; 1 MPa
Linear; 0,1 m/s; 1 Mpa
Rotation (long); 0,3 m/s; 1 Mpa
Rotation; 8h (short) 0,3 m/s; 1 Mpa
Rotation; 2 h 0,3 m/s
Rotation; 8 h 0,3 m/s
Cf53
V2A
Cf53
V2A
Cf53
V2A
Cf53
V2A
Cf53
V2A
Cf53
V2A
Nylon CF Slide
7,0
9,4
8,8
21,4
5,1
6,2
13,3
13,3
0,26
0,21
0,26
0,18
Taber test (weight loss in gram after 1000 cycles), 3 measurements.
