论文部分内容阅读
研究了在670℃下,振荡磁场双棍铸轧对7075铝合金成型板材微观形貌和硬度影响。结果表明,同传统方式铸轧相比,采用振荡电磁场铸轧板材的枝晶被严重碎断、细化和等轴化。在此条件下7075板材的表面及中心的偏析程度大幅减轻,并且在交变振荡场的作用下偏析完全消失。普通铸轧条件下板坯横向和轧向的HV硬度值分别为1104和1356 MPa;采用电磁场后,在交变振荡场下获得最大硬度为1615 MPa;除此之外,当磁场强度增加,板材性能会进一步提高。另外发现,无论在何种磁场条件下,升高浇注温度后,外加电磁场的细化作用效果增强。
The effect of oscillating magnetic double-stick casting on microstructure and hardness of 7075 aluminum alloy plate was studied at 670 ℃. The results show that, compared with the traditional way of casting, the dendrites of the sheet cast by the oscillating electromagnetic field are severely broken, refined and equiaxed. In this condition, the degree of segregation on the surface and center of 7075 slab is greatly reduced, and the segregation disappears completely under the action of alternating oscillating field. Under the condition of normal casting and rolling, the HV values of the slab in the transverse direction and the rolling direction are 1104 and 1356 MPa, respectively. After the electromagnetic field is applied, the maximum hardness is 1615 MPa under the alternating oscillation field. Besides, when the magnetic field intensity increases, Performance will be further improved. In addition, it was found that the refining effect of the applied electromagnetic field is enhanced no matter what magnetic field conditions are raised.