金属增材制造质量控制及复合制造技术研究现状

Review on Quality Control and Relevant Hybrid Technology in Additive Manufacturing of Metallic Materials

相比传统制造工艺,增材制造能够实现复杂结构金属部件的近净成形。然而,增材制造具有冷却速度快、热梯度大、非平衡凝固与往复热循环历史等特点,容易存在孔洞、残余拉应力、各向异性等缺陷,极大限制增材制造的进一步应用。复合增材制造技术是将传统制造方法与增材制造有机结合,充分发挥传统制造工艺在性能调控与尺寸精度等方面的优势,抑制单纯增材制造引起的各类缺陷,获得高质量、无缺陷的增材制造部件。本文首先揭示增材制造工艺缺陷的形成机理,明确工艺参数优化方法在缺陷改善方面的局限性,进而阐明复合增材制造的内涵,综述近年来增材制造与轧制、激光冲击强化、热等静压、热处理等复合制造技术的研究现状与工艺原理,探讨复合增材制造技术对不同缺陷的适用性,并对增材制造未来发展方向进行了展望。

Compared with conventional manufacturing processes,additive manufacturing is a technique used to produce near-net-shape and complex metal components.However,owing to the high cooling rates,high temperature gradients,non-equilibrium solidification,and multiple transient thermal cycles,defects such as porosities,residual tensile stress,and anisotropy are created during additive manufacturing,significantly restricting further applications.Hybrid additive manufacturing technology,which combines the conventional manufacturing method with additive manufacturing,exploits the conventional manufacturing method in terms of its performance control and dimensional accuracy.Therefore,defects created during metal additive manufacturing are eliminated,and defect-free additive manufactured components with high qualities are produced.With this background,this paper first reveals the formation mechanism of defects in the additive manufacturing process,and we discover that merely using the process parameter optimization method is inadequate to improve mechanical properties.The definition and classification of hybrid additive manufacturing are then discussed.The current research status and technical principles of hybrid manufacturing processes(i.e.,rolling,laser shock peening,hot isostatic pressing,and heat treatment)are analyzed.Moreover,the application range of various hybrid additive manufacturing technologies is discussed.Finally,the future development trend of the additive manufacturing process is predicted.