锌层对不同强度级别热镀锌板成形性能的影响  

Influence of galvanized layer on formability of hot-dipped galvanized sheet steel with different strength levels

作　　者：李涛[1] 王宝川[1] 姚野[1] 郑学斌[1] 金茹[1] 

机构地区：[1]首钢技术研究院,北京100043

出　　处：《锻压技术》2016年第1期48-51,共4页Forging & Stamping Technology

摘　　要：针对CR3,CR340LA,CR590DP,CR780DP四种不同强度热镀锌板,利用单向拉伸试验及极限拱高试验,对比分析了锌层对热镀锌板的力学性能指标和极限拱高的影响规律。结果表明,锌层与基板的变形能力不一致导致了热镀锌板与去除锌层基板的力学性能的差异,当基板变形能力高于锌层时,锌层的存在会引起热镀锌板强度提高,伸长率、n值、r值降低,当基板变形能力低于锌层时,锌层的存在会引起热镀锌板强度降低,伸长率、n值、r值提高;热镀锌板的变形能力不仅和本身的力学性能有关,也和板料与模具的接触摩擦状态有关,由于锌层的存在,在成形过程中会导致接触面摩擦恶化,影响热镀锌板的成形能力,后续的成形工艺设计应考虑锌层的影响。For the hot-dipped galvanized sheet steel CR3, CR340LA, CR590DP, CR780DP with different strength levels, the influence of galvanized layer on mechanical properties and limiting dome height were analyzed comparatively by uniaxial tensile test and limiting dome height test. The research results show that the difference between the formability of the galvanized layer and the uncoated substrate causes the different mechanical properties. When the formability of the uncoated substrate is higher than that of the galvanized layer, the strength of hot-dipped galvanized sheet steel increases, and values of elongation, n value, and r value decrease due to galvanized layer in existence, vice versa. The deformation ability of the hot-dipped galvanized sheet steel is not only related to its mechanical properties, but also to the contact state of the sheet metal and the die. Because of the existence of the galvanized layer, the friction of the contact surface becomes deterioration in forming, and the formability of the hot-dipped galvanized sheet is affected. As a result, the influence of the gal- vanized layer should be taken into consideration in the subsequent forming process design.

关 键 词：锌层 热镀锌板 力学性能 成形性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]