摘要
铝/钢复合结构结合了铝合金的低密度和钢的高强度、低成本等优良特性，在汽车轻量化制造领域具有良好的应用前景。利用焊接方法和增材制造可以实现铝/钢复合构件的快速制造，但铝和钢的物理性能差异较大且二者之间极易反应形成连续分布的脆硬Fe-Al金属间化合物，严重降低铝/钢异种金属界面及整个构件的力学性能。本文论述了铝/钢异种金属的焊接性，介绍了铝/钢异种金属焊接技术的发展现状及一些前沿的金属间化合物调控和消除策略，重点阐述了电弧增材制造和激光增材制造在铝/钢复合结构制备方面的应用及其与铝/钢电弧焊、激光焊的异同之处，最后对铝/钢异种金属焊接及增材制造的发展方向进行了展望。
随着“碳达峰、碳中和”战略目标纳入国家发展规划中，我国持续推进汽车产业结构和能源结构转型。在大力发展新能源汽车的同时，也希冀通过车身材料和结构轻量化的方法来降低能耗，实现节能减排。钢具有优异的力学性能和机械加工性能，且成本低，是汽车制造最常用的结构材料，但其较大的密度给车身轻量化带来了一定的挑
目前，常规的铝/钢复合结构件主要通过铝/钢异种金属的焊接进行连接成
本文总结了铝/钢异种金属的焊接性，介绍了一些前沿的金属间化合物调控和消除策略，阐述了电弧增材制造及激光增材制造铝/钢复合构件的发展现状，对比分析了增材制造技术与焊接方法在制备铝/钢复合结构方面的异同之处，并对铝/钢异种金属焊接及增材制造的发展方向提出了展望，旨在为铝/钢复合结构在汽车轻量化领域的实际应用提供理论和技术参考。
由于铝合金与钢的物理和化学性质存在明显差异，使得铝/钢异种金属的高质量焊接和增材制造存在一定的困难和挑战，具体表现在以下几个方面。
| Material | Density/ g·c | Melting point/ ℃ | Thermal expansion coefficient/×1 | Thermal conductivity/ W·(m·K | Specific heat capacity/J·(kg·K |
|---|---|---|---|---|---|
| Al | 2.7 | 660 | 24 | 237 | 1080 |
| Fe | 7.8 | 1536 | 11 | 80 | 795 |
图1 Al-Fe二元合金相图
Fig.1 Phase diagram of Al-Fe binary allo
图2 采用不同电弧焊接方法获得的铝/钢接头中焊缝/钢界面的微观形貌
Fig.2 Microstructures of the braze bead-steel interface in Al/steel joints obtained by TIG (a) and CMT (b) technologie
图3 不同啃削量下铝/钢电弧焊接头的界面组织形貌
Fig.3 Interface microstructures of Al/steel joint under different offset values: (a–b) 0 mm; (c–d) 0.1 mm; (e–f) 0.2 mm; (g–h) 0.3 m
图4 电弧增材制造SS316L/ER4043双金属结构表征
Fig.4 Characterization of the fabricated Al/steel bimetallic structure: (a) as-deposited component, (b) interfacial morphology; (c) inverse pole figure map and (d) phase map along the build directio
图5 电弧增材制造SS316L/ER4043双金属结构的形貌、反极图和相分布图
Fig.5 SEM images (a, d), inverse pole figure maps (b, e), and phase maps (c, f) of the SS316L/ER4043 bimetallic structure fabricated under low heat input and (a–c) high heat input (d–f
图6 电弧增材制造铝/钢构件的界面结构
Fig.6 Interfacial microstructures of the initial (a, c) and subsequent (b, d) Al/steel interface in additive manufactured Al/steel components under magnetic field (a–b) and without magnetic field (c–d
图7 铝/钢异种金属激光熔钎焊
Fig.7 Laser welding-brazing of 5754 aluminium and CRRA 1000 steel: (a) schematic of Al/steel laps, (b–c) microstructures of the interface between weld metal (WM) and steel for the specimens fabricated with welding parameter #1 (the spot location containing 1/2 aluminum and 1/2 steel) and parameter #2 (the spot location containing 1/3 aluminum and 2/3 steel
图8 添加钛中间层的铝/钢激光焊接过程示意图
Fig.8 Schematic illustration of the laser welding of 6022 aluminum alloy to DP590 dual-phase steel by adding Ti foi
图9 激光增材制造铝/钢构件的界面组织结构
Fig.9 Al-Cu-Ce-Zr alloy/316L stainless steel component fabricated by LPBF and powder LDED: (a) X-ray CT image of the interface, (b) phase map and inverse pole figure map of the interface corresponding to the region shown in the inset in Fig.9
图10 采用激光增材+真空辅助熔渗铸造技术制造的铝/钢构件
Fig.10 Al/steel components fabricated by laser additive manufacturing and vacuum-assisted melt infiltration castin
铁、铝两种元素的低固溶性是导致铝/钢焊缝冶金相容性差的根本原因。铝/钢焊接过程中会在界面附近生成多种脆硬的Fe-Al金属间化合物，造成铝/钢界面的脆性大幅增加，强度明显降低，使铝/钢异种金属的焊接成为一大难题。铝/钢焊缝凝固过程中，生成的IMCs的种类主要取决于实际的焊接温度和合金的化学成分，同时也受到扩散时间的影
异种金属焊接技术已发展较为成熟，常用的有激光焊（laser welding，LW
电弧焊具有设备成本低、效率高、操作灵活等优点，在车、船用铝/钢构件的焊接领域应用十分广泛。铝/钢电弧焊通常采用熔钎焊模式，即利用电弧对铝/钢界面加热时，高熔点的钢材不熔化，低熔点的铝合金母材及填充金属发生熔化并铺展在钢表面形成钎焊接头，而焊缝与铝之间形成熔化焊连
Sravanthi
对于具有复杂结构、特殊形状和尺寸的铝/钢构件，采用电弧焊方法很难实现其精确成形。突破传统电弧焊在铝/钢复杂结构生产方面的局限性，是推动航空航天、船舶和汽车轻量化行业发展亟需解决的问题之一。WAAM以焊接电弧为热源，可将同种或不同金属丝材熔化并进行逐层堆积，能够实现复杂结构件的一体化成形及可控制备，为解决上述难题提供了新方法。与电弧焊相比，WAAM过程不仅包含了相邻金属层之间的焊接，还涉及了熔融金属沉积过程的结晶行为以及增材热循环对已成形层和层间界面的多重热影响，其组织结构演变过程比电弧焊更为复杂，构件力学性能的调控难度更大。当然，现有的铝/钢电弧焊相关理论和工艺优化策略对WAAM仍具有一定的指导作用。
孔乐
在铝/钢之间添加中间层或通过给母材施加镀层能够有效改善铝/钢之间的冶金性能，抑制金属间化合物的产生，是目前改善铝/钢界面力学性能的重要途
铝/钢异种金属的激光焊是采用激光作为热源来实现铝合金与钢之间形成有效连接的方法，具有焊接速度快、能量密度高、热输入控制精确、焊接变形小等优点，被广泛用于汽车、船舶等工业领域铝/钢复合构件的连接成
王晓虹
激光增材制造技术是以激光束为热源，通过将加热熔化的金属材料逐层堆积成形来制取三维构件的方法，根据原材料形态（丝材或粉末）和成形方式的不同，可分为激光定向能量沉积和激光粉末床熔合技术。相比于电弧增材制造方法，激光增材制造的成形精度更高、工艺更稳定，是制备复杂结构金属构件的重要手段之一。但目前针对铝/钢复合结构激光增材制造的研究报道较少，仍处于初步探索阶段。
Kannan
此外，将激光增材制造与其他成形方法相结合，可以进一步发挥增材制造技术在多材料复杂结构件制备方面的独特优势。例如，Ghasri-Khouzani
铝/钢复合结构的高质量、可控制造是实现汽车轻量化的重要途径。本文回顾了铝/钢异种金属焊接及增材制造的研究现状，针对其发展趋势提出如下展望：
（1）异种金属增材制造技术能够克服传统焊接方法在复杂结构、特殊形状和尺寸多材料复合构件成形方面的局限性，具有广阔的应用前景。但目前对增材制造工艺和材料体系的开发十分有限，且缺乏对异种金属增材制造界面组织演变规律的认识，这些难题需要研究人员在未来去逐步攻克。
（2）采用电弧或激光作为热源进行铝/钢复合构件增材制造时，二者之间总是不可避免地形成大量以Fe-Al金属间化合物为主的脆性相，使界面成为裂纹萌生和扩展的主要路径，造成构件性能无法充分发挥。搅拌摩擦增材制造具有固相成形、工艺简单、节能环保等优势，将成为铝/钢复合结构制造的重要方法之一。另外，基于增材制造技术的复合成形方法、以及增减材混合制造、外场辅助增材制造技术也有独到优势，是重要发展方向。
（3）开发合适的中间层材料，使增材制造或焊接过程中铝/钢界面中形成韧性化合物或固溶体，而非脆硬的金属间化合物，降低界面脆性，提升界面结合强度。
（4）借助人工智能和数值模拟方法进行铝/钢复合结构增材制造的仿真、预测，优化制造工艺参数，减少试错成本，提升制造的成功率，节省工艺研发周期。
参考文献 References
Suski C A, Filho J F S, Cortez A et al. Journal of Cleaner Production[J], 2024, 449: 141833 [百度学术]
Ni Yang(倪 炀), Dong Xuefeng(董学锋). Automobile Technology & Material(汽车工艺与材料)[J], 2023, 7: 11 [百度学术]
Yang Y, Luo Z, Zhang Y X et al. Journal of Manufacturing Processes[J], 2024, 110: 376 [百度学术]
Silvayeh Z, Domitner J, Sommitsch C et al. Journal of Manufacturing Processes[J], 2020, 59: 456 [百度学术]
Peng Chen(彭 晨), Tan Guanhua(谭观华), Wang Shanlin(王善林) et al. Special Casting & Nonferrous Alloys(特种铸造及有色合金)[J], 2023, 43(2): 211 [百度学术]
Du M, Wang W Q, Zhang X G et al. Materials Science & Engineering A[J], 2022, 853: 143746 [百度学术]
Liu Aiguo(刘爱国), Guo Xiaomeng(郭效盟). Welding & Jointing (焊接)[J], 2023(11): 53 [百度学术]
Chen J, Feng Z L, Wang H P et al. Materials Science & Engineering A[J], 2018, 735: 145 [百度学术]
Shu X, Liang X Y, Liu J L et al. Materials Letters[J], 2024, 354: 135328 [百度学术]
Gotawala N, Shrivastava A. Materials Science & Engineering A [J], 2021, 825: 141900 [百度学术]
Zhang W C, Wang J, Zhu X L et al. Journal of Materials Research and Technology[J], 2024, 28: 3566 [百度学术]
Kannan R, Lee Y, Pierce D et al. Materials & Design[J], 2023, 231: 112003 [百度学术]
Ghasri-Khouzani M, Li X, Bogno A A et al. Journal of Manufacturing Processes[J], 2021, 69: 320 [百度学术]
Liu F C, Zhang Y M, Dong P S. Journal of Manufacturing Processes[J], 2022, 73: 725 [百度学术]
Liu F C, Dong P, Khan A S et al. Journal of Materials Processing Technology[J], 2022, 308: 117721 [百度学术]
Matsuda T, Hatano R, Ogura T et al. Materials Science & Engineering A[J], 2020, 786: 139437 [百度学术]
Huang J K, He J, Yu X Q et al. Journal of Manufacturing Processes[J], 2017, 25: 126 [百度学术]
Dang Z Y, Qin G L, Ma H. Materials Science & Engineering A [J], 2021, 822: 141689 [百度学术]
Yang J, Oliveira J P, Li Y L et al. Journal of Materials Processing Technology[J], 2022, 301: 117443 [百度学术]
Zhang Liping(张丽萍), Xie Jilin(谢吉林), Yu Xi(余 曦) et al. Aeronautical Manufacturing Technology(航空制造技术)[J], 2022, 65(21): 78 [百度学术]
Mahto R P, Bhoje R, Pal S K et al. Materials Science & Engineering A[J], 2016, 652: 136 [百度学术]
Ghari H, Taherizadeh A, Sadeghian B et al. Journal of Materials Research and Technology[J], 2024, 30: 2520 [百度学术]
Dang Z Y, Qin G L, Guo X Y. Journal of Materials Research and Technology[J], 2023, 27: 35 [百度学术]
Pourali M, Abdollah-zadeh A, Saeid T et al. Journal of Alloys and Compounds[J], 2017, 715: 1 [百度学术]
Li H, Zhang C X, Deng Y H et al. Journal of Materials Research and Technology[J], 2023, 26: 328 [百度学术]
Matsuda T, Hayashi K, Iwamoto C et al. Materials & Design[J], 2023, 235: 112420 [百度学术]
Dang Z Y, Qin G L, Zhao Y H et al. Journal of Materials Research and Technology[J], 2022, 21: 2215 [百度学术]
Hatano R, Ogura T, Matsuda T et al. Materials Science & Engineering A[J], 2018, 735: 361 [百度学术]
Jabar S, Barenji A B, Franciosa P et al. Materials & Design[J], 2023, 227: 111774 [百度学术]
Liu Tao, Gao Song, Ye Weicheng et al. Journal of Materials Research and Technology[J], 2023, 25: 5096 [百度学术]
Wang Yuanyi(王元一), Qiao Ke(乔 柯), Zhang Ting(张 婷) et al. Journal of Plasticity Engineering(塑性工程学报)[J], 2024, 31(3): 214 [百度学术]
Coroado J, Ganguly S, Williams S et al. The International Journal of Advanced Manufacturing Technology[J], 2022, 119: 367 [百度学术]
Shu F Y, Niu S C, Zhu B H et al. Optics & Laser Technology[J], 2021, 143: 107355 [百度学术]
Liu Y Q, Li Y X, Chen H et al. International Journal of Fatigue [J], 2024, 183: 108261 [百度学术]
Liu Y Q, Liu R L, Liu B et al. Materials Characterization[J], 2022, 186: 111811 [百度学术]
Hasanniah A, Movahedi M. Marine Structures[J], 2019, 64: 295 [百度学术]
Ma Y T, Dong H G, Li P et al. Materials & Design[J], 2023, 230: 111971 [百度学术]
Huda N, Chen J, Gerlich A P. Forces in Mechanics[J], 2023, 11:100192 [百度学术]
Chen Yajun(陈亚军), Li Siwei(李思伟), Meng Xianming(孟宪明) et al. Materials Reports(材料导报)[J], 2023, 37(13): 21080153 [百度学术]
Cai W Y, Chen Q, Wang Y J et al. Composites and Advanced Materials[J], 2022, 31: 1 [百度学术]
Li Shaowei(李绍伟), Wang Fuxin(王付鑫), Wu Kaiwei(吴恺威) et al. Special Casting & Nonferrous Alloys(特种铸造及有色合金)[J], 2020, 40(7): 723 [百度学术]
Liu J, Wu B T, Wang Z R et al. Materials & Design[J], 2023, 225: 111520 [百度学术]
Beygi R, Carbas R J C, Barbosa A Q et al. Materials Science & Engineering A[J], 2021, 824: 141812 [百度学术]
Ma L H, Xu Z Y, Zhang T et al. Journal of Advanced Joining Processes[J], 2024, 9: 100220 [百度学术]
Wang J, Ling X, Zhang W T et al. Journal of Materials Research and Technology[J], 2022, 21: 3086 [百度学术]
Joshani E, Beidokhti B, Davodi A et al. Journal of Alloys and Metallurgical Systems[J], 2023, 3: 100017 [百度学术]
Liu Y Q, Li F, Li Y X et al. Journal of Materials Research and Technology[J], 2024, 29: 933 [百度学术]
Wang D S, Dong Y C, Liu L M et al. Journal of Materials Research and Technology[J], 2022, 17: 1043 [百度学术]
Yang T, Dai W, Chen L et al. Journal of Materials Processing Technology[J], 2022, 299: 117372 [百度学术]
Li M F, Tao W, Zhang J Z et al. Materials & Design[J], 2022, 221: 111022 [百度学术]
Argumedo J L G, Mahmoudiniya M, Reinton T E et al. Journal of Materials Processing Technology[J], 2024, 325: 118305 [百度学术]
Squires L, Roberts E, Bandyopadhyay A. Nature Communications[J], 2023, 14: 3544 [百度学术]
Amiri V, Naffakh-Moosavy H. Journal of Advanced Joining Processes[J], 2024, 9: 100194 [百度学术]
Wen Y J, Zhang B C, Narayan R L et al. Additive Manufacturing [J], 2021, 40: 101926 [百度学术]
Wen Y J, Wu X K, Huang A K et al. Acta Materialia[J], 2024, 264: 119572 [百度学术]
Ning J S, Zhu L D, Wang S H et al. International Journal of Extreme Manufacturing[J], 2024, 6: 025001 [百度学术]
Sravanthi S S, Acharyya S G, Chapala P. Materials Today: Proceedings[J], 2019, 18: 2708 [百度学术]
Yagati K P, Bathe R N, Rajulapati K V et al. Journal of Materials Processing Technology[J], 2014, 214: 2949 [百度学术]
Yu Tengyi(余腾义), Li Wei(李 伟), Yu Gaoyang(喻高扬) et al. Iron Steel Vanadium Titanium(钢铁钒钛)[J], 2023, 44(5): 188 [百度学术]
Tan Pan(谭 攀), Sheng Chen(盛 陈), Qiu Chengguo(邱成果) et al. Transaction of the China Welding Institution(焊接学报)[J], 2023, 44(4): 98 [百度学术]
Kong Lele(孔乐乐). Research on Arc Additive Manufacturing Technology of 5083 Aluminum Alloy-Low Carbon Steel Heterogeneous Material Structure(5083铝合金-低碳钢异种材料结构电弧增材制造工艺研究)[D]. Dalian: Dalian University of Technology, 2020 [百度学术]
Miao Yugang(苗玉刚), Zeng Yang(曾 阳), Wang Teng(王 腾) et al. Transaction of the China Welding Institution(焊接学报)[J], 2015, 36(7): 5 [百度学术]
Miao Yugang(苗玉刚), Li Chunwang(李春旺), Yin Chenhao(尹晨豪) et al. Transaction of the China Welding Institution(焊接学报)[J], 2019, 40(12): 129 [百度学术]
Li Mingkun(李明琨), Chen Minchang(陈民昌), He Zizhi(何资帜). China Plant Engineering(中国设备工程)[J], 2019, 5: 151 [百度学术]
Kannan R, Pierce D, Nayir S et al. Journal of Materials Research and Technology[J], 2024, 29: 4537 [百度学术]
Karim M A, Jadhav S, Kannan R et al. Additive Manufacturing [J], 2024, 81: 104015 [百度学术]
Jiang Shuying(蒋淑英), Cai Chang(蔡 畅), Zhao Ming(赵 明) et al. Transaction of the China Welding Institution(焊接学报)[J], 2023, 44(7): 72 [百度学术]
Arghavani M R, Movahedi M, Kokabi A H. Materials and Design[J], 2016, 102: 106 [百度学术]
Liu Yibo(刘一搏). Research on Interface Jointing Behavior of Al/Steel Additive Manufacturing Structure and the Effect Mechanism of Magnetic Field(铝/钢结构增材连接界面行为及磁场作用机制研究)[D]. Harbin: Harbin Institute of Technology, 2016 [百度学术]
Wang Yaxin(王亚欣). Research on the Interface Structure Evolution and Control Mechanism of Al/Steel in Arc Additive Manufacturing under Magnetic Field(磁场作用下铝/钢电弧增材界面结构演化与调控机制研究)[D]. Harbin: Harbin Institute of Technology, 2019 [百度学术]
Ding K, Hu T H, Wu Ti H et al. Materials Science & Engineering A[J], 2023, 880: 145314 [百度学术]
Wang Xiaohong(王晓虹), Gu Xiaoyan(谷晓燕), Sun Daqian(孙大千). Journal of Mechanical Engineering(机械工程学报)[J], 2017, 53(4): 26 [百度学术]
Li T, Zhou D W, Yan Y L et al. Materials Science & Engineering A[J], 2020, 796: 139929 [百度学术]
Xie Yong(谢 勇). Design and Microstructure Control of Transition Layer of Steel/Aluminum Heterointerface Prepared by Laser Additive Manufacturing(激光增材制造钢/铝异质界面过渡层设计及组织调控)[D]. Suzhou: Soochow University, 2022 [百度学术]