WEAR CHARACTERISTICS OF 3D PRINTED PLASTIC GEAR WITH DIFFERENT INFILL PERCENTAGES

Abstract

Polymer gears have great potential in motion and power transmission since they offer many advantages over conventional metal gears. However, the use of polymer gears in industrial applications has been limited due to inadequate information with respect to their performance and designs. In this research work, our goal was to study and analyze the characteristics of a polymer gear produced from polylactic acid through the a three-dimensional (3D) printing process. Experiments involving polymer test gears were carried out on a test rig at three rotational speeds. The parameters studied during the investigation were the infill percentage, rotational speed, and load attendance. Four types of failure characteristics-namely, the formation of debris, micro-surface condition monitoring, weight loss, and thermal damage-were analyzed in the experiments. The investigation showed that the weight reduction wear rate was related to the development of debris and the condition of the gear. The test gear wear rate from the weight reduction through material scratching and breakage increased progressively under extreme wear conditions. Further thermal analysis and microstructure observations also revealed the impact of temperature from frictional heat on the amount of wear on the polymer gear. The higher the operating temperature, the higher was the amount of wear seen in the polymer gear.