Influence of TiN addition on densification behavior and mechanical properties of ZrB2 ceramics

TiN and TiCN coatings have garnered widespread attentions in the field of materials science and engineering because of their exceptional characteristics, including high melting point, excellent thermal conductivity, remarkable chemical stability, superior corrosion and wear resistance, and notable biocompatibility. These properties make them highly suitable for coating various alloys, and as a result, they have been successfully applied in numerous applications. The aim of this research study is to delve into the corrosion behavior of spark plasma sintered NiTi substrates that were coated with TiN and TiCN employing physical vapor deposition (cathodic arc technology). In order to comprehensively analyze the corrosion response, potentiodynamic polarization and electrochemical impedance spectroscopy techniques were employed. To gain deeper insights into the impact of the coating, a meticulous comparison was conducted between the corrosion resistance of the uncoated specimen and that of the coated ones. The results showcased a significant enhancement in corrosion resistance for both coated samples when compared to the uncoated NiTi substrate. However, it was found that the TiN-coated specimen showed even higher corrosion resistance than the TiCN-coated counterpart. These findings highlight the superiority of TiN coatings in terms of corrosion resistance when applied on the NiTi substrate.

Section: Introductionmentioning

confidence: 99%

Corrosion behavior of TiN and TiCN coatings synthesized by PVD on the spark plasma sintered NiTi substrate

Botshekanan,

Majidian,

Farvizi

2023

“…Non-oxide ceramics including nitride, carbide, and boride compounds of a few transition metal elements are categorized as ultra-high temperature ceramics (UHTCs). Based on their significant combination of characteristics such as high strength, high hardness, acceptable thermal shock resistance, high melting point, and machinability, these ceramics attracted a considerable amount of attention in applications like aerospace vehicles, propulsion systems, and in general, high-temperature industries [1][2][3][4][5]. Among the UHTCs, ZrB 2 -based ceramics are in priority and are the best candidates for applications like thermal protection systems (TPS) or refractory crucibles [6].…”

Section: Introductionmentioning

confidence: 99%

A TEM study of nanostructures and interfaces in the hot-press sintered ZrB2–SiC–Si3N4 composites

Bazhin,

Nikolaev,

Esthefania Quiroz Cabascango

et al. 2023

A fully dense ZrB2–30 vol% SiC composite containing 5 wt% Si3N4 and 4 wt% phenolic resin (1.6 wt% carbon) was sintered using the hot-pressing route under the external pressure of 10 MPa at 1900 ºC for 2 h. The microstructural evolution and interfacial phenomena were scrutinized using advanced microscopy facilities such as high-resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM). The FESEM images showed the ZrB2 and SiC grains without any evidence of Si3N4. The formation of the hexagonal BN (hBN) phase was proven in the sintered composite. The hBN nanosheets had a graphite-like morphology with an average thickness of 20 nm. This phase has a perpendicular orientation to the pressure direction and prevents abnormal ZrB2 grain growth. Two types of ZrB2/SiC interfaces were detected, which exhibited an amorphous phase along with the grain boundary and a clean/smooth interface, resulting from the Si3N4 addition. HRTEM and inverse fast Fourier transform (IFFT) observations disclosed that the d-spacing value in the ZrB2 grain (0.335 nm) is higher than those reported in the literature. Furthermore, it was found that the exerted pressure during the sintering distorted atomic planes. The presence of numerous dislocations within the ZrB2 grains confirmed dislocation creep as the main densification mechanism.

“…Among the ultra-high temperature ceramics, diborides including ZrB 2 have interesting structural, mechanical, and physical characteristics like high melting temperature, good stability against molten metals, high electrical and thermal conductivity, and high thermal shock resistance [16][17][18]. Therefore, they are great options for high temperature (higher than 2000 °C) thermomechanical structural applications [19][20][21][22]. To boost the ablation behavior of carbon-carbon composite materials, ZrB 2 -SiC coatings fabricated by the pack cementation method were used.…”

Section: Introductionmentioning

confidence: 99%

Microstructural characterization of ZrB2–SiC–Si–MoSi2–WC coatings applied by SPS on graphite substrate

Jaberi Zamharir,

Zakeri,

Jahangiri

et al. 2023

The aim of this research was to apply a protective composite coating made of ultra-high temperature ceramics (UHTCs) on the graphite substrates. The spark plasma sintering (SPS) method was used to apply this coating on the graphite substrate. First, efforts were made to choose the right chemical composition for the composite material of the coating and the sintering conditions (temperature, pressure, and holding time) for applying the coating. Then, single-layer coatings with the basic composition of ZrB2–SiC–Si with WC and MoSi2 additives in equal amounts of 1.25 and 3.75 vol% of each were successfully applied on the graphite substrates under sintering conditions of 1875±25 °C final temperature, 10 MPa initial pressure, 25 MPa final pressure and 5 min holding time. The presence of the Si element in the basic composition of these coatings, in addition to helping to form an intermediate diffusion layer at the interface between the composite coating and the graphite substrate, caused the strengthening of the joining despite the difference in the coefficient of thermal expansion between the graphite and the composite coating.