大步长静力隐式有限元方法具有快速的计算速度和较高的计算精度，在金属板 料的成形模拟领域中得到了广泛的应用． 在接触搜寻阶段，由大步长引起的大量历史接触 信息改变的特点使接触搜寻问题变得更困难，因此有必要针对该问题设计一种高效稳健 的搜寻算法． 基于主从面法的思想，提出了一种结合位置码法和 ADT(Alternating Ditigal Tree，交替数字二叉树)法的改进接触搜寻算法，并集成到自主研发的 QuickForm 软件中; 通过数值算例对该方法的计算性能进行了测试． 结果表明:改进算法具有良好的搜寻性 能，平均搜寻效率提升了 20% 左右．

The large step implicit FEMs have been widely used in the field of sheet metal forming due to its fast calculation speed and highly accuracy． Many historical contact information may be changed for the current time step in implicit FEMs which makes the contact searching problem more difficult，and a robust contact searching al- gorithm is necessary． Combining location code algorithm and Alternating Ditigal Tree (ADT) structure，an algo- rithm based on master-slave method was proposed for large step implicit FEMs，and it was integrated into the QuickForm software． The experimental results show that the algorithm has good search performance． For many complex forming parts，the average search efficiency is up to about 20%．