Forming limits of nickel coating on right region

• Published in: Transactions of Nonferrous Metals Society of China 2007-10, Vol.17 (5), p.913-918
• Main Author: 周里群 李玉平 周益春
• Format: Article
• Language: English
• Subjects: forming limit diagram; instability criterion; nickel coating; sheet metal forming; 不稳定性; 薄金属; 金属成形; 镍覆盖层
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(07)60199-X

The forming limits of nickel coating on the right region were studied, so as to direct the preparation of the material and help the production of workpieces. The electrodeposited nickel coating was prepared on steel substrate to form advanced structures, and its plastic instability was investigated by the Swift Plastic Instability Theory. By using the compound law for laminated sheet metals, explicit equations for the calculation of the instable eigen values were deduced. The forming limit diagrams of the nickel coating on the right region were plotted. It is exhibited that the forming limit of the coating sheet is between the forming limits of the individual nickel coating and steel substrate. The forming limit of the nickel coating is not so good as that of the steel substrate, and the forming limit strain of the coating sheet tends to diminish with the increase of thickness of the coating. The greater the normal anisotropic coefficient of the materials is, the better the forming limit is.