With the rapid development of modern science and technology, the requirements for the performance of polymer materials are getting higher and higher. Among polymer materials, PEEK materials have been widely recognized by the medical, electronic semiconductor and other industries due to their high strength, high modulus and wear resistance. The improvement of wear resistance has been a hot topic for customers to focus on PEEK and its modified materials in recent years.

Blending PEEK with other materials can improve its heat resistance and friction and wear resistance. The main modification methods of PEEK are as follows: 1) Inorganic filler modification; 2) Fiber reinforcement modification; 3) Polymer blending modification and surface modification. Next, the research on the above three categories will be shared.

1. Modification with inorganic fillers

Wang Qihua et al. [1] used nano-SiC to modify the wear resistance of PEEK. The results showed that this composite material would produce slight adhesion transfer and fatigue wear when it was worn against metal. Different nanoparticle sizes will cause different friction effects. Smaller particles will form a transfer film with excellent performance and better wear resistance.

Appropriate use of inorganic fillers to modify PEEK materials can not only improve the thermal stability of the material but also improve the polymer transfer film effect on the friction surface. However, the gradual increase of inorganic fillers will show a trend of first increasing and then decreasing wear resistance. At the same time, too much inorganic filler will make the PEEK modified material more brittle, which will have certain limitations in use. Friction and wear experiment

2. Fiber-reinforced modification

Carbon fiber and glass fiber have excellent affinity with PEEK, becoming the representative of fiber-reinforced PEEK. Fiber-reinforced PEEK can not only improve the mechanical properties of the material, but also improve the tribological properties of the material.

Wu Xinxin from Nanjing University of Science and Technology[2] studied the thermodynamic properties and friction and wear properties of carbon fiber reinforced PEEK materials. The results show that adding different amounts and types of carbon fiber (unoxidized or oxidized) to PEEK powder can effectively improve the wear resistance of the composite material, and the change trend of the wear rate of the CF/PEEK composite material is basically the same as the increase in the amount of addition, which is gradually decreasing first and then increasing, but the magnitude of the change is different.

3. Polymer blending and surface modification

Organic material blending is an important method for developing new materials. Organic material blends can be obtained by a simple method, and the resulting materials have comprehensive properties that the mixed components do not have.

Compared with pure PEEK material, the friction coefficient of PEEKFE20 material (PTFE and PEEK are mixed and modified in a ratio of 2:8) is more stable during the friction process, and the wear resistance is increased by 5-8 times.

Citation:

[1] Wang Qihua, Xue Qunji, Shen Weichang. Study on the wear mechanism of polyetheretherketone filled with nano-SiC and micro-SiC [J]. Functional Materials, 1999, 29(5): 558-560.

[2] Wu Xinxin. Study on carbon fiber reinforced polyetheretherketone composites and their friction and wear properties [D]. Nanjing University of Science and Technology, 2012