Table 1
Main properties of PI (GCTPTM).
| Density (kg/m3) | 1350 | Impact strength (kJ/m2) | 25 |
| Tensile Strength (MPa) | 95 | Thermal expansion coefficient (°C−1) | 4.8 × 10−5 |
| Elongation at break (%) | 7 | Tg (°C) | 260 |
| Flexural strength (MPa) | 150 | Thermal decomposition temperature (°C) | 240 |
Fig. 1
The schematic diagram of the friction pair.
Table 2
Chemical composition of GCr15 steel (wt %).
| C | Si | Mn | Cr | P | S | Fe |
|---|---|---|---|---|---|---|
| 0.95–1.05 | 0.15–0.35 | 0.2–0.4 | 1.30–1.65 | ⩽ 0.027 | ⩽ 0.02 | Remainder |
Fig. 2
Scanning electron micrograph of CF (a: untreated, b: 1wt% silane coating, c: 2wt% silane coating, and d: 3wt% silane coating).
Table 3
Surface elementary composition of carbon fibers.
| Surface treatment | Elementary composition / % | Atom ratio / % | ||||
|---|---|---|---|---|---|---|
| C | O | N | Si2p | O/C | N/C | |
| Untreated | 82.3 | 10.2 | 7.5 | – | 12.4 | 8.9 |
| 0.1% coating | 77.7 | 13.1 | 8.4 | 0.8 | 16.9 | 10.7 |
| 0.2% coating | 75.3 | 14.4 | 9.1 | 1.2 | 19.1 | 12.1 |
| 0.3% coating | 76.9 | 13.2 | 8.47 | 1.42 | 17.2 | 11.0 |
Fig. 3
Cross-sectional scanning electron micrographs of CF/PI (a: untreated, b: 1wt% silane coating, c: 2wt% silane coating, and d: 3wt% silane coating).
Fig. 4
The tensile strength of the composites (a: untreated, b: 1wt% silane coating, c: 2wt% silane coating, and d: 3wt% silane coating).
Fig. 5
SEM photographs of the composite after wear (a: untreated, b: 1wt% silane coating, c: 2wt% silane coating, and d: 3wt% silane coating).
Fig. 6
The coefficient of friction and wear rate of the composite (a: untreated, b: 1wt% silane coating, c: 2wt% silane coating, and d: 3wt% silane coating).
Fig. 7
SEM micrographs of transfer film on the coupling surface (a: untreated and b: 3wt% silane coating).