Wear and failure of polyoxymethylene/calcium carbonate nanocomposite gears

Abstract

Nanocomposite gears and standard mechanical testing specimens based on polyoxymethylene containing different fractions (0, 3, 6, and 9 wt%) of nanosized precipitated calcium carbonate particles were produced by using twin-screw extruder and injection molding machine. The wear and temperature of gears teeth were measured by a gear test rig. The morphologies of fractured gears teeth were analyzed by using scanning electron microscopy. Results of experiments indicate that the incorporation of CaCO3 nanoparticles into polyoxymethylene increases the flexural and heat resistance and reduces the magnitudes of wear and temperature of gears noticeably. The maximum flexural resistance is achieved by employing 3 wt% of CaCO3 nanoparticles. Gears containing 3 wt% of CaCO3 nanoparticles present the lowest wear rate, which is 61% smaller than that of neat polyoxymethylene gear. The life time (durability till failure) of nanocomposite gear was twofold as compared to neat polyoxymethylene gear. The nanocomposite gear showed abrasive-wear and brittle-fracture, yet the neat polyoxymethylene gear demonstrated prevailing cohesive wear and ductile failure.

Flame retardancy and physical-mechanical properties of poplar veneers impregnated by calcium carbonate

“…The reason is that sodium carbonate reacts with calcium chloride to form CaCO3. The ability of calcium carbonate to improve wear resistance has also been verified in plastics, rubber, and other materials (Chen et al 2005;Wen et al 2017;Mohsenzadeh et al 2019). An important reason is the high wear resistance of CaCO3 itself (Zeng 2010).…”

Effect of carbon fiber addition on the tribological properties of polyoxymethylene composites

“…POM is an engineering thermoplastic, which has been utilized in tribological applications as gears and bearing in the areas of electronics, automotive, and precision instruments. [ 33,34 ] In previous studies, [ 35,36 ] we reported that the addition of aramid fibers and CFs greatly improved the mechanical and tribological properties of POM and PPS/PTFE blends. We also found that the addition of PTFE particles was more advantageous to reduce the friction coefficient, and the presence of PTFE fibers significantly improved the impact strength of POM.…”

Synergetic impacts of two rigid nano‐scale inclusions on the mechanical and thermal performance of POM/carbon black/CaCO3 ternary nanocomposite systems

“…However, poor impact strength, high UV sensitivity, and low thermal resistances may restrict its further application. [1][2][3][4] To tailor the functionality of POM and extend its applications, several studies were conducted to achieve a higher toughness for POM composites reinforced by elastomers [5,6] and mineral fillers. [7,8] The toughening of POM by incorporating elastomers was reported in many studies.…”