论文部分内容阅读
研究了脉冲磁场下不同励磁电流和脉冲频率对Al-12.5Mg-6.7Si合金中Mg2Si组织的影响,通过扫描电镜(SEM)对组织进行了分析并进行了硬度测试。结果表明,随着励磁电流和脉冲频率的增加,组织中的初生Mg2Si和共晶Mg2Si相得到细化,与重力场时相比,初生Mg2Si的晶粒尺寸减小了36%,硬度也有所提高。但当频率超过2Hz时,会导致初生Mg2Si明显粗化,共晶Mg2Si由蠕点状变成针状,硬度也有所下降。励磁电流为15~18A,脉冲频率为1~2Hz的脉冲磁场可以显著改善Al-12.5Mg-6.7Si合金的显微组织和性能。
The influence of different excitation current and pulse frequency on the microstructure of Mg2Si in Al-12.5Mg-6.7Si alloy was studied. The microstructure was analyzed by scanning electron microscopy (SEM) and the hardness was tested. The results show that the primary Mg2Si and eutectic Mg2Si phase are refined with the increase of magnetizing current and pulse frequency. Compared with the gravitational field, the primary Mg2Si grain size is reduced by 36% and the hardness is also increased . However, when the frequency exceeds 2Hz, the primary Mg2Si will be obviously coarsened, and the eutectic Mg2Si will change from a creep point to an acicular point and the hardness will also decrease. Excitation current of 15 ~ 18A, pulse frequency of 1 ~ 2Hz pulsed magnetic field can significantly improve the Al-12.5Mg-6.7Si alloy microstructure and properties.