激光3D打印高强高韧TC4钛合金的组织与性能

Structure and Properties of Laser 3D Printing High Strength and High Toughness TC4 Alloy

摘要

采用SLM技术成形了TC4钛合金，基于Double Doelhert设计矩阵优化的3D打印试样的致密度达到99.9%，最佳打印的参数为：层厚30μm，激光功率310W，扫描速度1200mm/s，扫描间距0.1mm，风场数值24。由于激光选区熔化过程中的高激光能量密度和高扫描速度带来极快的冷却速度（10⁴~10⁷℃/s），激光选区熔化组织为近快速凝固的细小马氏体组织。研究了热处理制度与力学性能关系，表明低温热等静压+长时真空退火可以获得高强高韧性的3D打印钛合金，全面达到锻件的技术指标，可广泛应用于航空发动机零件的打印。

Abstract

The TC4 titanium alloy was formed by SLM technology. The density of the 3D printing specimen optimized based on the Double Doelhert design matrix optimization reached 99.9%. The parameters for optimal printing are: layer thickness 30μm, laser power is 310W, scanning speed is 1200mm/s, scanning spacing is 0.1mm, and wind field value is 24. Due to the high laser energy density and high scanning speed during the laser selective melting process, the laser selective melting structure is a fine martensite structure that solidifies nearly rapidly. The relationship between heat treatment systems and mechanical properties was studied. It indicated that the HIP and long-term annealing process can obtain a high-strength and high-toughness 3D printed titanium alloy, which can fully meet the technical indicators of forgings and can be widely used in the printing of aircraft engine parts.

关键词

3D打印 / 激光增材制造 / 钛合金 / 热处理

Key words

3D pringting / laser additive manufacturing / titanium alloy / heat treatment

参考文献

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