[Hetero-3D]
Thermo-physical properties of liquid and heterogeneous solidification behavior of powder metals for 3D printer

RESEARCH OVERVIEW

• Accurate thermal property measurements are necessary to clarify the effect of Titanium carbide (TiC) particles as having a heterogeneous nucleus. However, the results of previous experiments on Earth suggested that TiC particles are moved by a difference of density. The Electrostatic Levitation Furnace (ELF) and microgravity conditions are expected to play a key role in solving this issue.
• The goals of the Thermo-physical Properties of Liquid and Heterogeneous Solidification Behavior of Powder Metals for 3D Printer (Hetero-3D) investigation are:
  
  ・Measuring the thermal properties and solidification behavior of melting liquids with and without TiC particles. The effects of TiC on the thermal properties are to be clarified.
  
  ・Thermophysical properties: the temperature dependence of density, surface tension, and viscosity of the samples are measured.
  
  ・Solidification:the cooling curves from liquid state to the solid state of the samples are obtained. The solidification behavior is clarified for samples with and without TiC.
• The nucleation mechanism for the solidification phenomenon still has many unknown points. The mechanism can be clarified through the obtained fundamental data on melting and solidification. Specifically, controlling the solidified microstructure during the additive manufacturing of metallic products, and improvement of their properties, are expected to be realized as a result.

SPACE APPLICATIONS

Additive manufacturing is used to create many parts from metallic powder for aerospace applications. This investigation may help improve the production process and the quality of parts used for future space exploration. It also can contribute to improved techniques for experimental materials science in space.

EARTH APPLICATIONS

Improved understanding of thermal properties and solidification behavior has potential applications for additive manufacturing, welding and casting technology and could help improve the quality of industrial products.

OPERATIONAL REQUIREMENTS AND PROTOCOLS

The ELF body is assembled and installed in the Multi Purpose Small Payload Rack/Multi Purpose Small Payload Rack-2 (MSPR/MSPR2) in the Kibo Module. After setup, the investigations are operated from ground control as required by investigators at Space Station Integration and Promotion Center (SSIPC), Tsukuba Space Center. The experimental procedure is as follows:

The investigations are prepared by the crew inserting the Sample Holder into Sample Cartridge, and inserting the Sample Cartridge into the chamber of the ELF.

The Experimental Sample is inserted into the Experiment Volume by a Sample Release Rod, for the experiment run. The Sample is then charged/position controlled/heated and melted through electrodes and Power Lasers. The Sample properties are then measured through sensors and cameras.

When investigation operations are complete, recorded video, images, and data are downlinked to Earth. The ELF facility is then deactivated.