难熔金属材料增材制造工艺研究进展

难熔金属材料具有良好的高温力学性能和高温稳定性，常用于制备耐热部件，被广泛应用于航空航天、国防工业等领域。然而，难熔金属的熔点比较高，室温塑性延展性能不佳，使用传统的加工方式制备复杂结构件时存在加工困难等问题。增材制造作为一项新兴的技术，基于三维模型数据，以激光、电子束、特殊波长光源、电弧及其多种组合作为能量源，利用“离散-堆积”成形原理制造实体部件，制备零件的尺寸可以从微米级到米级，为难熔金属复杂结构件的制备提供了新的途径。本文首先概述了增材制造技术的分类、特点及其应用，然后介绍了增材制造技术制备难熔金属的现状以及目前存在的主要问题，最后综述了增材制造工艺调控难熔金属材料微观组织和力学性能的研究进展，并对增材制造技术在难熔金属领域应用的发展方向进行了展望。

Advances in Additive Manufacturing Processes for Refractory Metal Materials

Refractory metal materials exhibit outstanding high-temperature mechanical properties and high-temperature stability. It is often used in the preparation of heat-resistant parts, and is widely used in aerospace, defense industry and other fields. However, refractory metals have a relatively high melting point and poor plastic ductility at room temperature. Therefore, there are problems such as processing difficulties when using traditional processing methods to prepare complex structural parts. Additive manufacturing is an emerging technology based on three-dimensional (3D) model data, using lasers, electron beams, special wavelength light sources, arcs and their various combinations as energy sources. The "discrete-stacking" forming principle is used to fabricate solid parts, and the size of the prepared parts can be from microns to meters, which provides a new way for the preparation of complex structural parts of refractory metals. Firstly, the classification, characteristics, and applications of additive manufacturing technology were summarized in this article. Then, the current status of additive manufacturing technology for preparing refractory metals was introduced. The major challenges in additive manufacturing of refractory metal materials were discussed. Finally, the research progress of additive manufacturing technology in regulating the microstructure and mechanical properties of refractory metal materials were summarized. And the future development direction of additive manufacturing technology of refractory metals was prospected.