Effects of plasma rotating electrode process parameters on the particle size distribution and microstructure of Ti-6Al-4 V alloy powder

• Published in: Powder technology 2020-10, Vol.376, p.363-372
• Main Authors: Cui, Yujie, Zhao, Yufan, Numata, Haruko, Bian, Huakang, Wako, Kimio, Yamanaka, Kenta, Aoyagi, Kenta, Zhang, Chen, Chiba, Akihiko
• Format: Article
• Language: English
• Subjects: Alloy powders; Computational fluid dynamics; Computer applications; Cooling; Cooling rate; Electrodes; Fluid dynamics; Hydrodynamics; Martensite; Mathematical models; Microstructure; Monte Carlo simulation; Optimization; Particle size; Particle size distribution; Powder; Powder fabrication; Principal components analysis; Process parameters; Rotating plasmas; Rotation; Size distribution; Statistic analysis; Statistical models; Titanium base alloys; Vanadium
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2020.08.027

The starting powder quality significantly influences the process window optimization and properties of parts fabricated by additive manufacturing. In this study, we investigated the influence of plasma rotating electrode process (PREP) parameters on the particle size distribution and microstructure of Ti-6Al-4 V alloy powder. The martensite size in the powder decreased with increasing rotating electrode speed owing to the higher cooling rate. Numerical simulations using computational thermal fluid dynamics were found to be feasible for quantitative evaluation of the temperature variation, cooling rate, and powder size during PREP, which provide a new strategy to study the mechanism of powder formation. In addition, a statistical model combining principal component analysis and the Monte Carlo methods was proposed to evaluate the relationships between PREP parameters and average powder diameter based on the limited collected experimental data. The proposed statistical model can also be applied in research fields where multivariable problems exist. [Display omitted] •Influence of PREP parameters on particle size distribution and microstructure of Ti-6Al-4 V alloy was investigated.•Average powder diameter decreased with increasing rotational speed or diameter of Ti-6Al-4 V alloy electrode.•The variation in cooling rate under different PREP conditions was evaluated quantitively by numerical simulations.•Proposed statistical model can be applied to evaluate the relationships between PREP parameters and average powder diameter.