Experimental investigation on microstructure, mechanical properties and dust emission when milling Al-20Mg2Si-2Cu metal matrix composite with modifier elements

Sustainable manufacturing regulations are pushing manufacturing towards decreasing of manufacturing hazards including microparticles and ultrafine particles. Machining process such as milling produces dust that can be harmful for operators' health. The emission of this dust depends on workpiece materials (microstructure, mechanical properties) and machining conditions. The aim of this paper is to determine the effect of the microstructure and machining conditions on dust emission during dry milling of Al-20Mg(2)Si-2Cu metal matrix composite with addition of bismuth (Bi) and barium (Ba). Experiments were carried out using dry CNC milling by uncoated carbide tools. An aerodynamic particle sizer (APS) and a scanning mobility particle sizer (SMPS) were used to measure microparticles and ultrafine particles emission, respectively. It was found that the addition of 0.4wt% Bi and 0.2wt% Ba changed Mg2Si particle size and improved the hardness of composite. In addition, ultrafine particle number concentration, specific area concentration and mass concentration decreased with the addition of modifiers. It is also confirmed that cutting conditions and microstructure of workpieces have a direct effect on dust emission during the milling process.