Experimental study of temperature erosion tests on bidirectional coated and uncoated composites materials

Abstract

In this research work, temperature erosion wear tests, on composites materials (carbon fiber and glass fiber), were carried out. The tests were made on uncoated and coated materials using a polyester resin (Gelcoat), which is used to protect the leading edge of wind turbine blades against the weather and UV rays and is of interest, in this study, to know the behaviour of this coating subjected to hard particles erosion. The tests were performed at 50 °C, in order to simulate de extreme temperature in the coast of Oaxaca, Mexico, where some wind turbines are installed using blades made of fiberglass coated with gelcoat. Erosion tests were performed in a platform that was developed from the ASTM G76 standard. The rectangular samples had 25 × 18 mm and thickness of 4 mm. Sea sand from coast of Oaxaca was utilized as erosive particle. Three different impact angles were used 75°, 85° and 90°. The particle velocity was adjusted at 12 m s-1. To determine the mass loss, the samples were weighed before the test and reweighed every 2 min to measure the amount of mass loss until complete the 6 min of the test. In order to identify the wear mechanisms, Scanning Electron Microscopy was used. The average roughness (Ra) and profiles of the samples tested were determined with a 3D optical profilometer. The results showed that Carbon fiber composite material had 3 times more resistance to erosive wear than fiberglass.