China Foundry (May 2015)
Effect of excitation current intensity on mechanical properties of ZL205A castings solidified under a traveling magnetic field
Abstract
The effect of excitation current intensity on the mechanical properties of ZL205A castings solidified under a traveling magnetic field was studied. The results of the experiment indicate that the excitation current intensity of the traveling magnetic field has a great influence on the mechanical properties of the ZL205A castings. When the excitation current intensity is 15 A, the tensile strength and elongation of ZL205A alloy castings increase 27.2% and 67.7%, respectively, compared with those of the same alloy solidified under gravity. The improvement of mechanical properties is attributed to the decrease of micro-porosity in the alloy. Under the traveling magnetic field, the feeding pressure in the alloy melt before solidification can be enhanced due to the electromagnetic force. Moreover, the melt flow induced by the traveling magnetic field can decrease the temperature gradient. The feeding resistance will be increased because the temperature gradient decrease. So traveling magnetic field has an optimum effect on feeding.
