For decades, scientists and engineers have focused on improving the materials used for gears while attempting to overcome several challenges, such as gear teeth breaking at the root due to fatigue, wear of the teeth at the flank, local overheating, too much noise, shock loading or hard stops, and noise vibration issues.
Today sintered metal gears are being replaced with high-performance plastic gears in automobiles because the demand to lightweight vehicles and increase fuel efficiency is far from just a trend—it is driven by meeting new and upcoming legislation to reduce emissions, and this must be met with cost-effective solutions—so the research and testing to improve gear design continues.
One of the cost-effective solutions to lightweight an automobile is the start-stop motor in which gears are made out of plastics that have excellent mechanical and tribological properties. These plastic gears reduce weight and cost. Plastic gears are also used in other automotive applications, including engine management actuators and power boosting systems, such as electric power steering and electric brake boosting—but for this blog we will focus on the start-stop motor application and DSM's gear testing capabilities.