Authors: W Tillmann P S Hollingsworth G Fischer J Nellesen F Beckmann
Publish Date: 2013/11/08
Volume: 23, Issue: 3, Pages: 289-295
Abstract
Because of their excellent properties aluminum and its alloys cover a wide range of applications especially in the lightweight construction sector In order to reach a higher strength and wear resistance metal matrix composites MMCs are used Typically Al MMCs are manufactured by casting or extrusion processes The disadvantage of these production routes is a costintensive and timeconsuming finishing in terms of grinding and milling The technique of thermal spraying provides the possibility to coat aluminum parts with MMCs close to their final shape In addition to the shape accuracy the ductility and toughness of the coated parts are generally higher compared to extruded or casted parts This study describes the development of detonationsprayed boron carbide reinforced aluminum coatings on aluminum EN AW 5754 substrates The optimization of the coatings was focused on a homogeneous coating structure a low coating porosity a high deposition efficiency a high number of embedded carbides and a small percentage of oxides In continuous tensile tests the influence of the MMC coating on the tensile strength was determined Furthermore the tensile strength was investigated in a discontinuous tensile test step by step The different stages of deformation were analyzed by using micro computed tomography This method enables the observation of tensile specimens in 3D and consequently the site and moment of crack formation
Keywords: