Impact and melting dynamics of micron-sized particles on a liquid pool

<p>A detailed understanding of powder-melt pool interactions and powder melting is of great importance for predicting and controlling the workpiece quality during direct energy deposition, a form of metal additive manufacturing. In this work, an organic transparent model system was designed, in which impact and subsequent melting of paraffin wax particles (melting point: ≈60°C, diameter: 200-800 μm, impact velocity: 0.3-1.9 m/s) onto a pool of liquid paraffin with temperatures 100-130^oC was investigated. The micron-sized paraffin particles were created using a bulk emulsion method. Impact and melting behavior under different working conditions were visualized using high speed imaging. Two modes of particle-liquid interactions were observed: Penetration or suspension. The influence of particle size, particle impact velocity, and melt pool temperature on particle penetration and melting times, as well as penetration and melting depths were analyzed. Penetration depth and time increase linearly with particle size, whereas temperature and velocity have little effect on penetration depth. Penetration time increases with the increase of particle impact velocity. Melting time increases with particle size and decreases with impact velocity. The melting depth increases with particle sizer and particle impact velocity. The ratio of the cavity width to the penetration depth increases with the increase of particle impact velocity.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering & Materials Science

Year dc:date.available

2021

Author dc:creator

• xue, sida

Contributors dc:contributor

• Patricia Weisensee
• David Peters, Ramesh Agarwal

• additive manufacturing
• melting dynamics
• particle liquid interaction
• particle fabrication
• heat transfer
• melt pool
• Engineering
• Heat Transfer, Combustion
• Mechanical Engineering

Statement dc:rights

• I have not registered my thesis with the U.S. Copyright Office, and do not intend to.

Language dc:language

English (en)

Identifier

https://openscholarship.wustl.edu/eng_etds/562

OAI identifier oai:identifier

oai:openscholarship.wustl.edu:eng_etds-1620