Kim Dae Woong, Lee Dong Ho, Kim Jung-Su, Sohn Seok Su, Kim Hyoung Seop, Lee Sunghak
Center for Advanced Aerospace Materials, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Sci Rep. 2017 Aug 14;7(1):8110. doi: 10.1038/s41598-017-08681-9.
Pure Ti or Ti alloys are recently spot-lighted in construction industries because they have excellent resistance to corrosions, chemicals, and climates as well as various coloring characteristics, but their wide applications are postponed by their expensiveness and poor formability. We present a new fabrication process of Ti/Al clad sheets by bonding a thin Ti sheet on to a 5052 Al alloy melt during vertical-twin-roll casting. This process has merits of reduced production costs as well as improved tensile properties. In the as-twin-roll-cast clad sheet, the homogeneously cast microstructure existed in the Al alloy substrate side, while the Ti/Al interface did not contain any reaction products, pores, cracks, or lateral delamination, which indicated the successful twin-roll casting. When this sheet was annealed at 350 °C~600 °C, the metallurgical bonding was expanded by interfacial diffusion, thereby leading to improvement in tensile properties over those calculated by a rule of mixtures. The ductility was also improved over that of 5052-O Al alloy (25%) or pure Ti (25%) by synergic effect of homogeneous deformation due to excellent Ti/Al bonding. This work provides new applications of Ti/Al clad sheets to lightweight-alloy clad sheets requiring excellent formability and corrosion resistance as well as alloy cost saving.
纯钛或钛合金最近在建筑行业备受关注，因为它们具有出色的耐腐蚀性、耐化学性和耐候性以及各种着色特性，但由于成本高昂且成型性差，其广泛应用被推迟。我们提出了一种新的钛/铝复合板制造工艺，即在垂直双辊铸造过程中将薄钛板与5052铝合金熔体结合。该工艺具有降低生产成本以及改善拉伸性能的优点。在双辊铸造的复合板中，铝合金基体一侧存在均匀铸造的微观结构，而钛/铝界面没有任何反应产物、气孔、裂纹或横向分层，这表明双辊铸造成功。当该板材在350°C至600°C退火时，通过界面扩散扩大了冶金结合，从而使拉伸性能比按混合法则计算的性能有所提高。由于优异的钛/铝结合导致均匀变形的协同效应，其延展性也比5052-O铝合金（25%）或纯钛（25%）有所提高。这项工作为钛/铝复合板在需要优异成型性、耐腐蚀性以及节省合金成本的轻质合金复合板方面提供了新的应用。
