Impact of Unit Cell Size on the Mechanical Performance of Ti-6Al-4V Lattice Structure

doi:10.3969/j.issn.1674-0696.2025.12.03

Abstract

Abstract: Focusing on the Ti-6Al-4V lattice structures formed by laser powder bed fusion (LPBF) technology, the impact of various unit cell sizes on the mechanical properties of additive manufacturing titanium alloy lattice structures was investigated. Initially, four types of lattice structures composed of varying sizes of body-centered cubic (BCC) and face-centered cubic (FCC) unit cells were designed and additively manufactured via LPBF. Secondly, the surface morphology, geometric characteristics and manufacturing defects of the additively manufactured Ti-6Al-4V lattice structures were characterized by use of scanning electron microscope (SEM). Thirdly, a universal mechanical testing machine was employed to conduct quasi-static uniaxial compression tests on the four types of LPBF-fabricated lattice structures, and the impact of different unit cell sizes on the mechanical properties of the lattice structures were compared. Finally, the deformation modes of lattice structures with different unit cell sizes were analyzed by combining with the fracture morphology characteristics. The results indicate that compared to lattice structures with larger unit cell sizes, the specific elastic modulus and specific compressive strength of the RBCC lattice structure have increased by 34% and 32.7% respectively, compared to BCC; while the specific elastic modulus and specific compressive strength of the RFCC lattice structure have increased by 45.6% and 32% respectively, compared to FCC.

Key words: vehicle and mechatronics engineering; unit cell size; additive manufacturing; titanium alloy; lattice structure; mechanical properties

摘要： 以激光粉末床熔融技术（LPBF）成形的Ti-6Al-4V点阵结构为对象，研究不同晶胞尺寸对增材制造钛合金点阵结构力学性能的影响。首先，设计了不同尺寸的体心立方（BCC）和面心立方（FCC）晶胞组成的4种点阵结构，并采用LPBF对其进行了增材制造；其次，利用扫描电子显微镜（SEM）对增材制造Ti-6Al-4V点阵结构的表面形貌、几何特征和制造缺陷等进行了表征；再次，采用万能力学试验机对LPBF制备的4种点阵结构进行了准静态单轴压缩试验，比较了不同晶胞尺寸对点阵结构力学性能的影响；最后，结合断口形貌特征，分析了不同晶胞尺寸的点阵结构的变形模式。结果表明：与较大晶胞尺寸的点阵结构相比，RBCC点阵结构的比弹性模量和比抗压强度对比BCC分别提高了34%和32.7%，RFCC点阵结构的比弹性模量和比抗压强度对比FCC分别提高了45.6%和32%。

关键词: 车辆与机电工程；晶胞尺寸；增材制造；钛合金；点阵结构；力学性能

CLC Number:

REN Yi1,2，CAI Siyang1，LIU Zhuofan1, ZHAO Yucheng1, GAO Zehao1. Impact of Unit Cell Size on the Mechanical Performance of Ti-6Al-4V Lattice Structure[J]. Journal of Chongqing Jiaotong University(Natural Science), 2025, 44(12): 18-23.

任毅1，2，蔡锶杨1，刘卓凡 1，赵宇成1，高浩泽1. 晶胞尺寸对Ti-6Al-4V点阵结构力学性能的影响研究[J]. 重庆交通大学学报（自然科学版）, 2025, 44(12): 18-23.

References

［1］张卫红, 唐长红. 航空航天装备的轻量化: 挑战与未来［J］. 航空学报, 2024,45(5): 529965.
ZHANG Weihong, TANG Changhong. Lightweighting of aerospace and aeronautical equipment: challenges and perspectives［J］. Acta Aeronautica et Astronautica Sinica, 2024, 45(5): 529965.
［2］梁祖磊, 孟岩松, 赵嘉喜, 等. 增材制造点阵结构设计、制备及性能研究进展［J］. 中国有色金属学报, 2025,35(1): 34-56.
LIANG Zulei, MENG Yansong, ZHAO Jiaxi, et al. Research progress on design, preparation and properties of additive manufacturing lattice structures［J］. The Chinese Journal of Nonferrous Metals, 2025, 35(1): 34-56.
［3］吴文旺, 夏热. 轻质点阵超结构设计及多功能力学性能调控方法［J］. 力学进展, 2022,52(3): 673-718.
WU Wenwang, XIA Re. Design of lightweight lattice meta-structures and approaches to manipulate their multi-functional mechanical properties［J］. Advances in Mechanics, 2022, 52(3): 673-718.
［4］杨鑫, 马文君, 王岩, 等. 增材制造金属点阵多孔材料研究进展［J］. 材料导报, 2021,35(7): 7114-7120.
YANG Xin, MA Wenjun, WANG Yan, et al. Research progress of metal lattice porous materials for additive manufacturing［J］. Materials Reports, 2021, 35(7): 7114-7120.
［5］任毅, 冉威, 蒲林, 等. SLM成形Ti-6Al-4V层状混合点阵结构的力学性能和吸能特性研究［J］. 重庆交通大学学报(自然科学版), 2024,43(6): 118-126.
REN Yi, RAN Wei, PU Lin, et al. Mechanical properties and energy absorption characteristics of SLM-formed Ti-6Al-4V layered hybrid lattice structure［J］. Journal of Chongqing Jiaotong University (Natural Science), 2024, 43(6): 118-126.
［6］徐聪, 张越, 马小敏, 等. 仿金刚石晶格构型点阵材料的变形机制及力学性能［J］. 复合材料学报, 2025,42(7): 4185-4197.
XU Cong, ZHANG Yue, MA Xiaomin, et al. Deformation mechanism and mechanical properties of diamond-like lattice materials［J］. Acta Materiae Compositae Sinica, 2025, 42(7): 4185-4197.
［7］段晟昱, 王潘丁, 刘畅, 等. 增材制造三维点阵结构设计、优化与性能表征方法研究进展［J］. 航空制造技术, 2022,65(14): 36-48.
DUAN Shengyu, WANG Panding, LIU Chang, et al. Research progress on design, optimization and performance characterization of additive manufactured 3D lattice structures［J］. Aeronautical Manufacturing Technology, 2022, 65(14): 36-48.
［8］ PARK K M, ROH Y S, LEE B C. Effects of the unit-cell size and arrangement on the compressive behaviors of lattice structures in powder bed fusion additive manufacturing［J］.Results in Materials, 2024, 22: 100587.
［9］ YANG Lei, HAN Changjun, WU Hongzhi, et al. Insights into unit cell size effect on mechanical responses and energy absorption capability of titanium graded porous structures manufactured by laser powder bed fusion［J］.Journal of the Mechanical Behavior of Biomedical Materials, 2020, 109: 103843.
［10］徐仰立, 张冬云, 胡松涛, 等. 结构尺寸对多孔Ti6Al4V力学性能的影响［J］. 稀有金属材料与工程, 2020, 49(5): 1736-1742.
XU Yangli, ZHANG Dongyun, HU Songtao, et al. Unit cell size effect on mechanical properties of Ti6Al4V porous structure［J］. Rare Metal Materials and Engineering, 2020, 49(5): 1736-1742.
［11］ REN Yi, NIE Yu, RAN Wei, et al. Mechanical properties and energy absorption of soft-hard dual phase lattice structures manufactured via selective laser melting［J］. Metals and Materials International, 2024, 30(2): 303-314.
［12］ BAI Long, XU Yue, CHEN Xiaohong, et al. Improved mechanical properties and energy absorption of Ti6Al4V laser powder bed fusion lattice structures using curving lattice struts［J］. Materials & Design, 2021, 211: 110140.
［13］ ZHANG Bi, LI Yongtao, BAI Qian. Defect formation mechanisms in selective laser melting: A review［J］.Chinese Journal of Mechanical Engineering, 2017, 30(3): 515-527.
［14］ ECHETA I, FENG Xiaobing, DUTTON B, et al. Review of defects in lattice structures manufactured by powder bed fusion［J］.The International Journal of Advanced Manufacturing Technology, 2020, 106(5): 2649-2668.
［15］ ZHAO Miao, LIU Fei, FU Guang, et al. Improved mechanical properties and energy absorption of BCC lattice structures with triply periodic minimal surfaces fabricated by SLM［J］.Materials, 2018, 11(12): 2411.
［16］ SOKOLLU B, GULCAN O, KONUKSEVEN E I. Mechanical properties comparison of strut-based and triply periodic minimal surface lattice structures produced by electron beam melting［J］.Additive Manufacturing, 2022, 60: 103199.

[1]	GU Runping, LI Rui. Route Network Based on Strict Hub Improvement [J]. Journal of Chongqing Jiaotong University(Natural Science), 2025, 44(7): 110-117.
[2]	WANG Chang1,2, CHENG Meng3, MA Shuai2. Case Study on Accident Caused by Loss of Tail-Rotor Effectiveness [J]. Journal of Chongqing Jiaotong University(Natural Science), 2022, 41(04): 126-132.
[3]	ZHU Jinfu1, MA Ruixin1,2, PENG Anna1, YAN Chen1. Flight Schedule Optimization in Multi-airport System Based on Particle Swarm Optimization Algorithm [J]. Journal of Chongqing Jiaotong University(Natural Science), 2021, 40(09): 1-8.
[4]	CAO Jianqiu, XU Peng,ZHANG Guangyan. Path Planning of UAV Based on Hybrid Ant Colony Algorithm under Greedy Strategy [J]. Journal of Chongqing Jiaotong University(Natural Science), 2021, 40(09): 9-16.
[5]	JIN Huibin1, HU Zhanyao2, YU Guihua2. Pilots Attention Allocation Behavior in Single-Engine Failure Scenario [J]. Journal of Chongqing Jiaotong University(Natural Science), 2021, 40(04): 1-5.
[6]	LI Nan1, JIAO Qingyu1, ZHANG Liandong2, FAN Rui1. Taxi Time Prediction of Departure Aircraft [J]. Journal of Chongqing Jiaotong University(Natural Science), 2021, 40(03): 1-6.
[7]	LI Nan, QIANG Yigeng, FAN Rui. Aircraft Flight Trajectory Clustering Based on Trajectory Compression [J]. Journal of Chongqing Jiaotong University(Natural Science), 2021, 40(01): 1-6.
[8]	ZHAO Guihong1, QIN Zhen1, LI Jianfu2. Optimization Algorithm and Implementation of Dispatched Vehicles between Several Flights in Condition of Flights Delay [J]. Journal of Chongqing Jiaotong University(Natural Science), 2020, 39(10): 5-9.
[9]	CHU Yanchang, CHEN Feichao, HOU Yunyan. Coordinated Development of Civil Aviation in Beijing, Tianjin and Hebei Based on the Synergy Model of Composite System [J]. Journal of Chongqing Jiaotong University(Natural Science), 2020, 39(10): 18-23.
[10]	LIU Lingli1, YU Meichen1, WANG Yue1, YUN Tianyu2. Applicability of Revised SCQ-MD Scale in Airport Pilots [J]. Journal of Chongqing Jiaotong University(Natural Science), 2020, 39(09): 46-46.
[11]	WANG Lili, LIU Ziang. Reroute Planning for Parallel Route [J]. Journal of Chongqing Jiaotong University(Natural Science), 2020, 39(08): 45-50.
[12]	CHU Yanchang, CHEN Feichao. Evaluation of Operation Efficiency of China’s Airport Industry Based on Super-efficiency DEA-Malmquist Model [J]. Journal of Chongqing Jiaotong University(Natural Science), 2019, 38(12): 115-122.
[13]	ZHANG Zhaoning,CHEN Weibo. Evaluation of Terminal Area Utilization Rate Based on Entropy Method [J]. Journal of Chongqing Jiaotong University(Natural Science), 2019, 38(11): 98-103.
[14]	WANG Jiening1,2, ZHANG Congjun1,2, FANG Xiaodan1,2 , SUN Xiaomeng1,2. LEADSTO Dynamic Simulation Analysis on ATC Pressure Generation Process [J]. Journal of Chongqing Jiaotong University(Natural Science), 2019, 38(10): 116-120.
[15]	LIU Jixin, ZENG Xiaoyu, YIN Minjia, ZHU Xuehua. Stress Level Prediction of Controller Based on Cumulative Logistic Regression Model [J]. Journal of Chongqing Jiaotong University(Natural Science), 2019, 38(03): 97-102.