Interfacial Characterization and High‐Temperature Property of NbB₂+NbC Nanoparticles‐Reinforced 2219Al Matrix Composite Synthesized by Melt Spinning

Abstract

Aluminum alloys have been widely used in aerospace, automotive, military, and other fields due to their low density, high strength, good processing formation performance, and excellent wear resistance. [1][2][3] Al-Cu alloys belong to the high-strength aluminum alloy, they possesses high strengths at room temperature; however, their strengths decrease significantly at high temperatures due to the coarsening of θ 0 precipitates. [4,5] Adding ceramic particles is an effective method to improve the high-temperature properties of the aluminum alloys. [5,6] The properties, sizes, and distribution of the ceramic particles, the interfacial bonding between the matrix and reinforcing phase, and the preparation process are the crucial factors that determine the properties of particle-reinforced Al-Cu matrix composites. [7][8][9] As reinforcing particles of the composites, they should possess excellent physical and chemical properties such as a high melting point, high hardness, high elastic modulus, low thermal expansion, good chemical stability, and corrosion resistance. For now, the most commonly used reinforcing particles include borides, carbides, and oxides, such as TiB 2 , [10,11] ZrB 2 , [12] TiC, [13] and Al 2 O 3 . [14] NbC ceramic particles possess a high melting point (3490 C), high hardness (HV 2400), a high elasticity modulus (338.5 GPa), a low coefficient of linear expansion (6.5 Â 10 À6 K À1 ), and high chemical and physical stability. [15] The melting point, hardness, elasticity modulus, and coefficient of thermal expansion of NbB 2 are 3050 C, 2600 kg mm À2 , 445 GPa, and 7.44 Â 10 À6 K À1 , respectively. Its chemical and physical properties are also very stable. [16] The lattice parameters of NbB 2 (hexagonal structure) and NbC [face centered cubic (FCC) structure] are a ¼ b ¼ 0.3086 nm, c ¼ 0.3306 nm, and a ¼ b ¼ c ¼ 0.447 nm, respectively. They may have the following orientation relationships with α-Al:

Effect of nano‐Al2O3 on the microstructure and properties of NbB2‐NbC composite coatings prepared by plasma spraying

“…Torabi et al 4 fabricated NbC‐NbB 2 nanocomposite by mechanochemical method using Mg, B 2 O 3 , Nb, and C powder mixtures. Recently, Ding et al 43 produced Al metal matrix composites reinforced with NbB 2 ‐NbC nanoparticles by melt spinning method using Al, Nb, and B 4 C powders as raw materials. It was revealed that the addition of NbB 2 and NbC helped to improve the room‐temperature and high‐temperature properties of the alloy.…”

“…For exam 42 ]. Pyrolysis of polycarbosilane polyme by Key et al 43 X-ray diffraction (XRD, Rigaku DMAX-2500) was performed to determine the phase compositions of powders and as-sprayed coatings. Microstructural studies were done using a scanning electron microscope (SEM, HITACHI S-4800) equipped with an energy dispersive spectroscope (EDS).…”

“…For exam 42 ]. Pyrolysis of polycarbosilane polyme by Key et al 43 composite powder retained the original phase in the plasma spraying process, and only part of Al 2 O 3 changed from stable α-Al 2 O 3 phase to metastable γ-Al 2 O 3 phase. This is because the critical nucleation free energy of γ-Al 2 O 3 was lower than that of α-Al 2 O 3 , so the metastable phase γ-Al 2 O 3 was formed in the NbB 2 -NbC-Al 2 O 3 coating under a high cooling rate.…”

“…For exam 42 ]. Pyrolysis of polycarbosilane polyme by Key et al 43 mixture at 2/2/1 molar weight. Torabi et al 4 fabricated NbC-NbB 2 nanocomposite by mechanochemical method using Mg, B 2 O 3 , Nb, and C powder mixtures.…”

“…For exam 42 ]. Pyrolysis of polycarbosilane polyme by Key et al 43 as substitutes for high-temperature structural applications. 8,9 As we all know, refractory coatings have superior oxidation resistance properties in high-temperature environments.…”