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| Mechanical disturbance on cracks formation in mushy zone of oscillating mold |
| LIN Ren-gan，MENG Xiang-ning，ZHU Miao-yong |
| School of Materials and Metallurgy， Northeastern University， Shenyang 110819， Liaoning， China |
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Abstract The formation of initial cracks on continuous casting slabs is greatly effected by the vibration of the mold. The initial solidifying shell in the meniscus was considered as simple beam in this study， and the stress states under the non-uniform loads by ferrostatic pressure and flux channel pressure was expatiated in solidification front at representative oscillation time based on the material mechanics theory and non-sinusoidal oscillation waveform， the possibility of generating initial cracks were discussed quantitatively， and the measures for controlling initial cracks were proposed in combination with the rule of influence of oscillation parameters on bending stress. The results show that the maximum bending stress in initial solidifying shell can reach to 148.4 kPa in vertical direction， the initial cracks generated easily because of the critical fracture stress is 14.7 kPa when the solid fraction increased to 0.9. The maximum bending stress decreases about 36.3，24.6，16.4 kPa when the vibration frequency and the amplitude have a reduction of 75 min-1， 1.5 mm， and the oscillation factor increases by 0.15. The initial cracks formation can be restrained by decreasing oscillation frequency and amplitude and increasing non-sinusoidal oscillation factor properly.
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Received: 17 July 2014
Published: 13 April 2015
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2015, Vol. 34 
