Adamiak Marcin, Appiah Augustine Nana Sekyi, Woźniak Anna, Nuckowski Paweł M, Nazarov Shuhratjon Abdugulomovich, Ganiev Izatullo Navruzovich
Materials Research Laboratory, Faculty of Mechanical Engineering, Silesian University of Technology, 18A Konarskiego Street, 44-100 Gliwice, Poland.
Department of Machinery and Devices, Engineering and Technological Faculty, Technological University of Tajikistan, Dushanbe 734061, Tajikistan.
Materials (Basel). 2023 Mar 27;16(7):2671. doi: 10.3390/ma16072671.
Aluminum-lithium alloys have the potential for use in aerospace applications, and improving their physical, mechanical, and operational characteristics through alloying is a pressing task. Lithium, with a density of 0.54 g/cm, enhances the elastic modulus of aluminum while reducing the weight of the resulting alloys, making them increasingly attractive. Adding transition metal additives to aluminum alloys enhances their strength, heat resistance, and corrosion resistance, due to their modifying effect and grain refinement. The study aimed to investigate the impact of titanium content on the microstructure, corrosion resistance, and hardness of Al-Li alloys. Four alloys were prepared with varying amounts of titanium at 0.05 wt%, 0.1 wt%, 0.5 wt%, and 1.0 wt%. The results showed that the microstructure of the alloy was modified after adding Ti, resulting in a decrease in average grain size to about 60% with the best refinement at 0.05 wt% Ti content. SEM and EDS analysis revealed an irregular net-shaped interdendritic microstructure with an observed microsegregation of AlLi compounds and other trace elements at the grain boundaries. The samples showed casting defects due to the high content of Li in the alloy, which absorbed air during casting, resulting in casting defects such as shrinkage holes. The corrosion resistance test results were low for the samples with casting defects, with the least resistance recorded for a sample containing 0.1 wt% Ti content, with more casting defects. The addition of Ti increased the microhardness of the alloy to an average of 91.8 ± 2.8 HV.
铝锂合金在航空航天应用方面具有潜力，通过合金化改善其物理、机械和使用特性是一项紧迫任务。锂的密度为0.54 g/cm，可提高铝的弹性模量，同时降低所得合金的重量，使其越来越具有吸引力。向铝合金中添加过渡金属添加剂可增强其强度、耐热性和耐腐蚀性，这归因于它们的变质作用和细化晶粒。该研究旨在探究钛含量对铝锂合金微观结构、耐腐蚀性和硬度的影响。制备了四种含钛量分别为0.05 wt%、0.1 wt%、0.5 wt%和1.0 wt%的合金。结果表明，添加钛后合金的微观结构发生了改变，平均晶粒尺寸减小至约60%，在钛含量为0.05 wt%时细化效果最佳。扫描电子显微镜（SEM）和能谱分析（EDS）显示，枝晶间存在不规则网状微观结构，在晶界处观察到AlLi化合物和其他微量元素的微观偏析。由于合金中锂含量高，样品出现铸造缺陷，铸造过程中吸收了空气，导致出现缩孔等铸造缺陷。有铸造缺陷的样品耐腐蚀性测试结果较低，含0.1 wt%钛且铸造缺陷较多的样品耐腐蚀性最差。添加钛使合金的显微硬度平均提高到91.8±2.8 HV。
