The use of multi-materials structures is nowadays one of the most sought solutions to decrease weight and reduce both emission of greenhouse gases and fuel consumption in the automotive industry. Dissimilar joining of aluminum (Al) alloys to steels by fusion-based welding technologies is often difficult to achieve as a result of the significant mismatch in these materials’ physical and chemical properties. Moreover, when mixed in the liquid state, hard and brittle intermetallic compounds are easily formed. Due to characteristics that include high processing speed, flexibility and energy density, multiple attempts have been made to join Al to steel using laser-based processes. This thorough review article provides a comprehensive and exhausting analysis of the recent achievements and progress on joining of Al alloys to steel by various laser-based joining processes, including laser keyhole welding, laser welding-brazing, laser-arc welding, laser-assisted friction stir welding, laser roll pressure welding and joining based on laser additive manufacturing. This paper also evaluates the joining conditions, filler materials, phase constitution, microstructure, mechanical properties and joining mechanisms associated to each process. Furthermore, special emphasis is given to factors affecting the joint strength such as welding defects, joint geometry, intermetallic compounds formation and interfacial strength. The review is then concluded with an outlook providing the summary and future trends of this field.

多材料结构的使用是当今汽车行业最受追捧的减轻重量和减少温室气体排放和燃料消耗的解决方案之一。由于这些材料的物理和化学性能显着不匹配，因此通过基于熔合的焊接技术将铝 (Al) 合金与钢进行异种连接通常很难实现。此外，当以液态混合时，容易形成硬而脆的金属间化合物。由于具有高加工速度、灵活性和能量密度等特性，人们多次尝试使用基于激光的工艺将铝与钢连接起来。这篇全面而详尽的综述文章对通过各种基于激光的连接工艺（包括激光锁孔焊、激光焊接-钎焊、激光弧焊、激光辅助摩擦）在铝合金与钢的连接方面取得的最新成果和进展进行了全面而详尽的分析。基于激光增材制造的搅拌焊、激光辊压焊和连接。本文还评估了与每个过程相关的连接条件、填充材料、相构成、微观结构、机械性能和连接机制。此外，特别强调了影响接头强度的因素，如焊接缺陷、接头几何形状、金属间化合物的形成和界面强度。然后，审查结束时提供了该领域的摘要和未来趋势的展望。包括激光锁孔焊、激光焊-钎焊、激光-电弧焊、激光辅助搅拌摩擦焊、激光滚压焊和基于激光增材制造的连接。本文还评估了与每个过程相关的连接条件、填充材料、相构成、微观结构、机械性能和连接机制。此外，特别强调了影响接头强度的因素，如焊接缺陷、接头几何形状、金属间化合物的形成和界面强度。然后，审查结束时提供了该领域的摘要和未来趋势的展望。包括激光锁孔焊、激光焊-钎焊、激光-电弧焊、激光辅助搅拌摩擦焊、激光滚压焊和基于激光增材制造的连接。本文还评估了与每个过程相关的连接条件、填充材料、相构成、微观结构、机械性能和连接机制。此外，特别强调了影响接头强度的因素，如焊接缺陷、接头几何形状、金属间化合物的形成和界面强度。然后，审查结束时提供了该领域的摘要和未来趋势的展望。本文还评估了与每个过程相关的连接条件、填充材料、相构成、微观结构、机械性能和连接机制。此外，特别强调了影响接头强度的因素，如焊接缺陷、接头几何形状、金属间化合物的形成和界面强度。然后，审查结束时提供了该领域的摘要和未来趋势的展望。本文还评估了与每个过程相关的连接条件、填充材料、相构成、微观结构、机械性能和连接机制。此外，特别强调了影响接头强度的因素，如焊接缺陷、接头几何形状、金属间化合物的形成和界面强度。然后，审查结束时提供了该领域的摘要和未来趋势的展望。