Indian Journal of Pure and Applied Physics

Open Access Open Access  Restricted Access Subscription Access

Effects of Niobium and Vanadium on the Properties of Porous TiMoCuAg High-Entropy Alloys


Affiliations
1 Department of Chemistry, Faculty of Science (Girls), Al-Azhar University, Yousef Abbas Str., Nasr City, P.O. Box: 11754, Cairo, Egypt
2 Mining, Petroleum, and Metallurgical Engineering Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt
3 Powder Technology Department, Manufacturing Technology Institute, Central Metallurgical R and D Institute, P.O. 87, Helwan, Cairo 11421, Egypt

Powder metallurgy was used to create porous TiMoCuAgV HEA (VHEA) and TiMoCuAgNb HEA (NbHEA) using 0, 10, and 20 wt.% from ammonium hydrogen carbonates (AHCs) as a space holding material. Samples were mixed with AHCs as a foaming agent. All samples were compacted at 400 MPa and sintered at 1250oC. X-ray diffraction, scanning electron microscopy, and energy dispersive analyses were performed for phase identification, microstructure observation, and elemental composition, respectively. Fabricated HEAs density values were estimated according to Archimedes' principle. Also, hardness and Young's modulus were determined. The addition of vanadium (V) was shown to exceed that of niobium (Nb) in increasing the HEA Young's modulus without AHCs. The corrosion characteristics of the prepared HEAs in corrosive media were estimated by the weight loss (WL) method, indicating good improvement by adding either V or Nb. The findings showed that the 10-NbHEAs in SBF had the highest improvement values, where the CR value was 0.94 mm/y lower than other investigated media. Additionally, 10-VHEAs in a simulated body fluid solution (SBF) and hydroxyapatite (HA) corroded more rapidly than 10-NbHEAs. After the corrosion test, the surface morphology showed a protective layer for 10-NbHEAs in SBF media. Also, the surface morphology is well-defined as smooth and uniform in HA media for 10- NbHEAs and 20-NbHEAs, which agrees with WL and corrosion rate values. Generally, VHEAs have higher corrosion resistance than NbHEAs.

Keywords

High entropy alloys; TiMoCuAgV HEA; TiMoCuAgNb HEA; Hardness; Microstructure
User
Notifications
Font Size

Abstract Views: 47




  • Effects of Niobium and Vanadium on the Properties of Porous TiMoCuAg High-Entropy Alloys

Abstract Views: 47  | 

Authors

Ghalia A Gaber
Department of Chemistry, Faculty of Science (Girls), Al-Azhar University, Yousef Abbas Str., Nasr City, P.O. Box: 11754, Cairo, Egypt
Lamiaa Z Mohamed
Mining, Petroleum, and Metallurgical Engineering Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt
Omayma A Elkady
Powder Technology Department, Manufacturing Technology Institute, Central Metallurgical R and D Institute, P.O. 87, Helwan, Cairo 11421, Egypt
Ayman H Elsayed
Powder Technology Department, Manufacturing Technology Institute, Central Metallurgical R and D Institute, P.O. 87, Helwan, Cairo 11421, Egypt
Shimaa A Abolkassem
Powder Technology Department, Manufacturing Technology Institute, Central Metallurgical R and D Institute, P.O. 87, Helwan, Cairo 11421, Egypt

Abstract


Powder metallurgy was used to create porous TiMoCuAgV HEA (VHEA) and TiMoCuAgNb HEA (NbHEA) using 0, 10, and 20 wt.% from ammonium hydrogen carbonates (AHCs) as a space holding material. Samples were mixed with AHCs as a foaming agent. All samples were compacted at 400 MPa and sintered at 1250oC. X-ray diffraction, scanning electron microscopy, and energy dispersive analyses were performed for phase identification, microstructure observation, and elemental composition, respectively. Fabricated HEAs density values were estimated according to Archimedes' principle. Also, hardness and Young's modulus were determined. The addition of vanadium (V) was shown to exceed that of niobium (Nb) in increasing the HEA Young's modulus without AHCs. The corrosion characteristics of the prepared HEAs in corrosive media were estimated by the weight loss (WL) method, indicating good improvement by adding either V or Nb. The findings showed that the 10-NbHEAs in SBF had the highest improvement values, where the CR value was 0.94 mm/y lower than other investigated media. Additionally, 10-VHEAs in a simulated body fluid solution (SBF) and hydroxyapatite (HA) corroded more rapidly than 10-NbHEAs. After the corrosion test, the surface morphology showed a protective layer for 10-NbHEAs in SBF media. Also, the surface morphology is well-defined as smooth and uniform in HA media for 10- NbHEAs and 20-NbHEAs, which agrees with WL and corrosion rate values. Generally, VHEAs have higher corrosion resistance than NbHEAs.

Keywords


High entropy alloys; TiMoCuAgV HEA; TiMoCuAgNb HEA; Hardness; Microstructure