Investigating the Microstructure and Mechanical Properties of Tantalum Sintered Parts by Hot Pressing in a Vacuum

Subject Areas : Materials synthesis and charachterization

Farrokh Najafzadegan ^{1 *} , Alireza Khodabandeh ² , Hossein Yoozbashizadeh ³ , Morteza Tamizifar ⁴

1 - Department of Materials Science and Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 - Department of Materials Science and Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
3 - Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran.
4 - School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran, Iran.

Received: 2025-04-18 Accepted : 2025-09-15 Published : 2023-10-01

Keywords: Tantalum, Hot Pressing, Ductility, Mechanical Properties,

Abstract :

This study investigates the consolidation of pure tantalum powder via hot pressing (HP) to enhance its ductility and mechanical properties. The effects of sintering temperature and time on the microstructure and mechanical properties of sintered tantalum were examined. Density was measured using the Archimedes method, while microstructure was analyzed via optical and scanning electron microscopy. Compression tests evaluated mechanical properties. Results revealed that reduced porosity and altered porosity morphology significantly improved mechanical properties. A 17.6% density increase led to a 100% enhancement in compressive strength, ductility, and hardness. Optimal properties were achieved at 1600°C, yielding a hardness of 345 HV, compressive strength of 1278 MPa, and ductility of 34%.

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