多种倾角类比SLM成形TC4复杂曲面构件性能

Performance of TC4 Complex Surface Components Formed by SLM with Various Inclination Angles

为探究SLM成形TC4钛合金高性能复杂曲面构件,选择激光束垂直基板扫描,成形与Y轴成0°、30°、45°、60°四个典型倾角结构作类比分析,探讨倾斜角度对SLM成形件表面形貌、内部组织及力学性能的影响。为提高SLM成形复杂构件的综合性能,对45°倾斜角试样进行固溶处理和完全退火处理分析,讨论热处理对45°倾斜角试样的拉伸性能及断口形貌的影响。结果表明:不同倾角的TC4试样表面存在球化、沟壑、沟脊和未溶粉末粘连等缺陷,且倾斜角度越大,表面沟壑和沟脊缺陷越明显;而试样倾角变化对其内部组织和显微硬度影响较小。经950℃固溶处理后的试样,α相溶解,强度明显下降;固溶处理试样断口形貌韧窝面积大且深,试样塑性增加,与强度分布特征相符。由此可推测,SLM成形复杂曲面构件的表面缺陷较多,但内部组织性能相对均衡,且固溶处理能够减少内部缺陷,提高构件综合性能。

In order to explore the SLM forming of TC4 titanium alloy high-performance and complex curved components, the laser beam was selected to scan in the perpendicular substrate direction, and the forming and Y-axis were formed at four typical inclination angles of 0°, 30°, 45°, and 60°, to investigate the influence of the tilt angle on the surface morphology, internal structure and mechanical properties of the formed parts. In order to improve the comprehensive properties of the complex components formed by the SLM, the solution treatment and complete annealing treatment of 45° inclination angle specimens were analyzed, and the effect of heat treatment on the tensile properties and fracture morphology of the 45° inclination angle specimens was discussed. The results showed that there were defects such as spheroidization, gully, ridge and undissolved powder adhesion on the surface of TC4 samples with different inclination angles, and microhardness had little effect. After solution treatment at 950 ℃, the α phase dissolved, and the strength decreased significantly;the fracture morphology of the solution treated sample had a large and deep dimple area, and the plasticity of the sample increased, which was consistent with the strength distribution characteristics. It can be speculated that there were many surface defects of complex curved components formed by the SLM, but the internal structure and properties were relatively balanced, and the solution treatment can reduce internal defects and improve the comprehensive performance of the components.