Influence of pouring methods on filling process, microstructure and mechanical properties of AZ91 Mg alloy pipe by horizontal centrifugal casting
Tóm tắt
Pouring position as the input heat source has great influence on the temperature field evolution. In this study, the Flow3D simulation software was applied to investigate the influence of pouring methods (with fixed or moving pouring channel) on AZ91 Mg alloy horizontal centrifugal casting (HCC) process. The simulation results show that the moving pouring channel method can effectively increase the cooling rate and formability of casting pipe. The casting experiment shows that an AZ91 Mg alloy casting pipe with homogeneous microstructure and clear contour was obtained by the moving pouring channel method, and the grain size of the casting pipe is significantly decreased. Meanwhile, serious macro-segregation appeared in the AZ91 casting pipe by the fixed pouring channel HCC process. Compared with the fixed pouring channel, the moving pouring channel can remarkably improve the ultimate tensile strength and elongation of the AZ91 HCC pipe from 142.2 MPa to 201.5 MPa and 6.2% to 6.7%, respectively.
Tài liệu tham khảo
Pollock T M. Weight loss with magnesium alloys. Science, 2010(328): 986–987.
Xu Jun, Liu Guojun, Zhang Shaoming, et al. Rheo-diecasting of AZ91D magnesium alloy. Rare Metals, 2010, 29(5): 542–546.
Kaneko T and Suzuki M. Automotive applications of magnesium alloys. Materials Science Forum, 2003, 419–422.
Zhang Baiming. Centrifugal Casting. Beijing: China Machine Press, 2004. (In Chinese).
Teng Haitao, Zhang Xiaoli, Qi Kai, et al. Microstructure and Mechanical Properties of Centrifugal Casting AZ61A Magnesium Alloy Tube. Rare Metal Materials and Engineering, 2008, 28(3): 464–467. (In Chinese).
Zeng Xingwang, Cheng Liliang, Liu Ruixiang. Study of the Numerical Simulation of the Centrifugal Casting. Foundry, 2004, 53(4): 310–313. (In Chinese)
Zeng Xingwang. Solution to Practical Flowing Process of Centrifugal Casting. Huazhong University of Technology, 2004, 7–8. (In Chinese)
Xu Zhian, Song Nannan, Tol Rob Vol, et al. Modelling of horizontal centrifugal casting of work roll. Material Science and Engineering, 2012, 33(1):1–5.
Wang Cao. Study on Forming Technology of AZ91 Magnesium Alloy Sheet by Centrifugal Casting and Rolling. Shenyang: Shenyang University of Technology, 2017. (In Chinese).
Geng Xingming. Guide for production of permanent mould casting. Beijing: Chemical Industry Press, 2008. (In Chinese).
Geng Haoran, Teng Xinying, Wang Yan, et al. Casting aluminum and magnesium alloy. Chemical Industry Press, 2008. (In Chinese).
Song Nannan, Wu Shiping, Luan Yikun, et al. Numerical simulation and hydraulic experiment of horizontal centrifugal casting. Acta Physica Sinica, 2009, 58(s1): 112–117.
Du X H and Zhang E L. Microstructure and mechanical behavior of semi-solid die-casting AZ91D magnesium alloy. Materials Letters, 2007, 61: 2333–2337.