Wang J.-J.,Ningbo Powerway Alloy Materials Co. |
Liu Q.,Ningbo Powerway Alloy Materials Co. |
Cao A.-Q.,Dalian University of Technology |
Wang T.-M.,Dalian University of Technology |
And 2 more authors.
Zhuzao/Foundry | Year: 2014
The macrostructure, microstructure and hardness of horizontal continuously cast billets of C3604 brass alloy were investigated, which was solidified under the actions of no electromagnetic stirring and with electromagnetic stirring, separately. The experimental results show that the structure of C3604 brass alloy with electromagnetic stirring is refined effectively and the distribution of Pb element and the hardness over the cross-section tends to uniform. Among the used currents and frequencies, the stirring effect of 35 Hz and 100A is the best. The touching waterlines appearing on ingot surface change from a certain angle with the horizontal to vertical after the application of electromagnetic stirring. It illustrates that the solidification interface of upper and bottom locates at the same place in the crystallizer, which is helpful to eliminate the phenomenon of terminal solidification zone drifting upward the geometrical center without stirring resulting from the differential cooling effect between bottom and top. With the application of electromagnetic stirring, the size of copper drilling scraps is uniform and the machinability is good. The effect of straightening is stable with homogeneous straightness, not bending and the strip product qualified rate is higher than before.
Cao Z.,Dalian University of Technology |
Chen F.,Dalian University of Technology |
Li X.,Dalian University of Technology |
Guo J.,Ningbo Powerway Alloy Materials Co. |
And 2 more authors.
Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering | Year: 2015
The paper studied the change rule of the forepart of initial solidified shell, cross-section structure and elements distribution of horizontal continuous casting Zn-Cu alloy billets under electromagnetic field. The results show that the forepart position changes with the casting speed, pouring temperature and current intensity. Among these parameters, casting speed plays the most important role. It is only adjusting the corresponding casting speed according to the current strength and the pouring temperature that can improve the structure and reduce segregation. The forepart moves backwards by enhancing the current and the casting speeds. When the liquid-solid interface locates in the interspace between the cooling water jacket and the electromagnetic stirrer, the inverse segregation of Cu can be effectively suppressed. Electromagnetic field removes the nonuniform cross-section structures and the difference between the final solidification area and billet geometric center, and refines the dendrite structure. Stirring does not completely eliminate the deep gray dendritic copper rich phases in the edge or center of the billets, instead of slightly larger dendrite sizes and the small edge-center structure difference. When casting speed and current intensity is 3 m/h and 100 A, respectively, the most uniform and refined structure is obtained, while no obvious change can be seen for other currents and frequencies. The addition of Ti cannot refine the billet structure or eliminate the inverse segregation, but make the melt sticky with poor fluidity. ©, 2015, Rare Metals Materials and Engineering Press. All right reserved.