The influence of process conditions on the microstructure of porous W-Cu, fabricated by freeze casting using tert-butyl alcohol as the freezing agent, was investigated. The slurries containing 10 vol% of WO3-CuO powder were prepared by milling with a small amount of citric acid and polyethylene glycol as dispersants. The slurries with dispersion stability were frozen in a mold with the lower part cooled to -20°C, followed by sublimation in a vacuum to remove the freezing agent. The sintered W-1 vol% Cu in a hydrogen atmosphere exhibited aligned pores with the size of 50 μm, which were generated by sublimation of directionally solidified tert-butyl alcohol crystals. In the cross-section of the specimen, hexagonal pores corresponding to the crystal structure of tert-butyl alcohol were observed. Microstructure analysis of the struts revealed that Cu was distributed non-uniformly due to the mutual insolubility and low wettability of the W-Cu system.

1. Introduction 
2. Experimental Section 
3. Results and Discussion 
4. Conclusion 
Funding
Conflict of Interest 
Data Availability Statement 
Author Information and Contribution 
Acknowledgments
References

• 김영민(서울과학기술대학교 신소재공학과) | Youngmin Kim (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea)
• 김지영(서울과학기술대학교 신소재공학과) | Ji Young Kim (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea)
• 손민주(서울과학기술대학교 신소재공학과) | Minju Son (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea)
• 권원용(서울과학기술대학교 신소재공학과) | Wonyong Kwon (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea)
• 이의선(서울과학기술대학교 신소재공학과) | Eui Seon Lee (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea)
• 오승탁(서울과학기술대학교 신소재공학과) | Sung-Tag Oh (Department of Materials Science and Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea) Corresponding author