| Polyamide 66 (PA66) is commonly used machine parts manufacturer of engineering plastics. As the PA66 molecular structure of regular and high-crystalline, compared with other engineering plastics, having highlighted the self-lubricating, wear-resistant, PA66 is a better material. But PA66 can not be used as high-speed friction material, restricted the expansion of its applications. It's imperative to make the in-depth study on the friction and wear behavior of PA66 composites and to prepare the outstanding performance of integrated PA66-based composite. Discussion and analysis of the friction and wear mechanism has a practical significance.The friction and wear properties as well as the mechanical properties of PA66 composites which filled with GB, PTFE, PPS and GF were studied by melt blending in this paper. To analyze the mechanism of wear and the dispersion of fillers,the worn suifaces and fracture surfaces of PA66 composites and the transfer film were observed by means of scanning electron microscope(SEM) and stereomicroscope. using DSC discussed GB filling modifier of the impact of crystal materials. The effect of GB on crystallization property of composites was preliminary studied by DSC; For PA66/GF composites used for automotive engine periphery providing valuable reference datas, the effect of antioxidant system on thermal-oxidative aging properties of PA66/GF composite was researched. Simultaneously, the friction and wear behavior of different thermal-oxidative aging properties PA66/GF composites was inspected.The following concusions can be drawn from the paper: (1) PA66/GB composite tensile strength, hardness could be significantly increased with the addition of the rigid hollow glass bead particles, but its content should less than 6%.The addition of GB promoted crystallization temperature about 10℃, increased crystallinity what was favorable to improve mechanical property. As the content GB was less than 8%,the rate of wear of composites was smaller than the net, especially when its content was 2%, the rate of wear reduced by a half. With the increment of the concentration of GB, wear mode of composite deposit is gradually shifted from adhesion wear to abrasive wear. When the concentration of GB reached 2 wt%, composite had a smooth surface and only exhibites slight abrasive wear. In short, filling modification of PA66 with GB, not only improved the system of the tensile strength, hardness, wear resistance, and maintained the impact strength, but also effectively reduce the cost, had a good prospect and practical value.(2) With filling PTFE on the basis of PA66/2%GB,the friction coefficient could be reduced,as the content was 2% and 3%,the rate of wear was also decreased, fatigue wear was improved. PTFE showed as fiber-forming in composite, and PTFE in PA66/2% GB/ PTFE composite focused on the distribution of around GB.(3) With filling PPS on the basis of PA66/2%GB, mechanical property was reduced,but it was better than PA66/PPS composite under the same content PPS. The friction coefficient and wear could be reduced. In comparison to PA66/PPS composite,the existence of GB decreased the thickness of transfer film, inhibited adhesive wear,reduced wear.(4) The mechanical properties of PA66/GF had a greater increase than PA66, but it depended on the length of GF. Copper salt antioxidant H3336 on PA66/GF composite had best long-term thermal-oxidative stability, 1098 (blocked phenol), 168 (phosphite antioxidant category), H3336 played the role of anti-synergy. The sample which had better thermal-oxidative stability showed better friction and wear property,that explained the fit antioxidants could improve the friction and wear property. It provided a new perspective of the study to tribological research.
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