An investigation of machinability of magnesium alloys

In this study, influence of aluminium (Al) content on the machinability of AS series magnesium (Mg) alloys (AS11, AS21, AS41, AS61, AS91) was investigated. Microstructural characterizations were performed by microscopic examination and xray diffraction analysis (XRD). Room temperature mechanical properties of the alloys were determined by hardness measurements and tensile tests. Machinability characteristics of the alloy were investigated by selecting different processing parameters. The results of machinability were evaluated by surfaces roughness and cutting force values, chips, wear and flank built-up (FBU) at the tip of the cutting tool during machining. Microscopic examination, mechanical test results and machinability of the alloys are evaluated in the light of the literature data. In the results, the amount of intermetallic phases observed in the microstructure of AS series Mg alloys increased with an increase of Al content in the alloy. Intermetallic phase in the microstructure with an increase of Al content have an effect on the machinability and mechanical properties of alloys. Yield and tensile strengths and hardness of the alloy increased by addition of Al, but elongation % decreased with increasing Al content. The machinability of the alloy decreased depending on both the increase in Al content and cutting speed. In addition, at all alloys, cutting force and surface roughness increased with an increase of cutting speed.