| Casting numerical simulation technology can predict the defect location and its causes in the casting,which is beneficial to the more reasonable design of the casting process.Due to the complex shape of propeller blades and harsh working environment,it is more stringent for its casting process and corrosion resistance.In this paper,casting simulation software ProCAST was used to optimize the simulation process of propeller casting,and the effect of rare earth elements on the corrosion resistance of AlMg5Si1 alloy was studied.The results are as follows:?1?The casting system of the propeller is created by 3D-CAD software,including the entities of the propeller casting,the gating system,the overflows,the metal collectors and the exhaust passages.Then,the casting numerical simulation is carried out by the casting simulation software.According to the production experience,the pouring temperature,pouring velocity,filling pressure and die temperature affect the casting quality greatly.Therefore,the orthogonal experiment L9?34?of four factors and three levels was designed,and the best casting process parameters were obtained:the pouring temperature of 720°C,the gate velocity of 35m/s,intensification pressure of 110 MPa and the die temperature of 220°C.?2?The simulation results show that there is almost no shrinkage and looseness in the casting body.At the same time,the microstructure analysis shows that the blade structure of the propeller is dense,which indicates that the casting process can be effectively improved casting qualityby the simulation of the optimized process parameters.?3?The effects of different rare earth additions on the microstructure and corrosion resistance of AlMg5Si1 alloy were studied.The results show that the AlMg5Si1 alloy is mainly?-Al and Mg2Si,and a small amount of AlCe3,Al11La3 and La5Si4 appear.When the amount of mixed rare earth is 0.6%0.9%,the grain of AlMg5Si1 alloy is obviously refined and the distribution of Mg2Si phase is more uniform.?4?The intergranular corrosion results show that AlMg5Si1Re0.9 alloy has the best intergranular corrosion resistance,and its maximum intergranular corrosion depth and average corrosion depth are 77.0?m and 64.3?m,respectively.?5?The electrochemical corrosion test results show that the corrosion current density of AlMg5Si1Re0.9 alloy is the smallest,its value is 2.89*10-6A·cm-2,the corrosion rate of AlMg5Si1Re0.9 alloy is the smallest in seawater and the corrosion resistance is the best.?6?The corrosion potential of AlMg5Si1Re0.9 alloy was greatly changed from-1.29V to-0.75V during the whole immersion process.The corrosion current density of AlMg5Si1Re0.9 alloy increased to the maximum,and then begins to decrease tends to be stable. |
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