Investigation on the Wear Regime of Plastic Gears Sliding Against Metal Gears

<div class="section abstract"><div class="htmlview paragraph">The use of plastic gears has expanded due to their lightweight properties, low noise emission, and cost-effective manufacturing. For instance, in the transportation equipment industry, some metal gears are being replaced with plastic gears. To achieve further size and weight reduction, gears must be able to withstand higher loads without damage. Gears have various modes of damage. Since there are different types of wear, each with different factors, it is important to identify the factors and take appropriate countermeasures. In gear meshing, there are many factors that affect wear, so restricted-factor tests are required to confirm the effectiveness of countermeasures.</div><div class="htmlview paragraph">The purpose of this study is to elucidate the wear regime in high-load gear meshing and then to establish a simplified evaluation method replicating the meshing of gears for wear resistance focusing on the relative sliding between the two surfaces of metal and plastic.</div><div class="htmlview paragraph">In the evaluation, changes in wear morphology over time were investigated to attempt to elucidate the wear mechanism. The reciprocating sliding test was selected as the evaluation method for wear resistance. The lubrication environment, sliding speed, and surface pressure of the gear test were matched with those of actual gear contact condition to simulate the relative sliding between metal and plastic in the gear test. The test was also performed with different roughness on the metal side to partially reproduce the wear morphology seen in the gear test.</div></div>