Li Jiadong

不同Mg/Si比对含Zn的Al-Mg-Si合金再结晶组织及性能的影响

为改善Al-Mg-Si系合金汽车板综合性能，通过浇铸法制备出3组合金成分铸锭，并经过均匀化、热轧、中间退火、冷轧，获得1 mm厚的合金板材.合金板材经560 ℃固溶30 min后，立即在100 ℃条件下预时效8 h，室温停放14天，模拟铝板转运存储过程，并拉伸变形2%，再在185 ℃下进行20 min烘烤处理，实现烘烤硬化.采用金相显微镜、装备电子背散射衍射的扫描电镜对合金进行显微组织观察及织构分析，通过万能电子试验机进行力学性能测定，研究不同Mg/Si比和高Zn元素对合金再结晶组织及织构、烘烤硬化性以及腐蚀敏感性的影响.结果表明，Mg/Si比相等合金再结晶组织更加均匀细小，平均晶粒尺寸190 μm，存在相对较少的Cube织构{001} 和较多的P型织构{011} ；高Mg合金、高Si合金局部晶粒粗大，Cube织构{001} 较多，P型织构{011} 较少；预时效后，Mg/Si比相等合金强度较高，且烘烤硬化性优异，烤漆硬化增量达到107 MPa；烤漆后，更多的Zn原子扩散到晶界上，强化晶界微电流反应，欠时效态Mg/Si比相等合金较高Mg合金、高Si合金抗腐蚀敏感性降低，被腐蚀深度为121 μm.

Camera mathematic model of the molten steel level detection in the strip casting process

A CCD system was designed to detect the molten steel level in the strip casting process. According to the image computing method, camera mathematic model of the molten steel level detection was established. Then an experiment was carried out to calibrate the model parameters and the precision of the mathematic model was tested. The result illustrates that the camera mathematic model and calibrate method of the molten steel level are feasible, which show high levels of precision and can be applied in the industrial line for the strip casting.