A Thermodynamic Assessment of the Cr-Zr System

Keng, Kejun; Hämäläinen, Marko; Luoma, Rauno

doi:10.1515/ijmr-1993-840104

Cited by 13 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, the eutectic Cr-Zr interlayer and a lot of cavities at the coating/alloy interface were formed due to the Cr-Zr interdiffusion. The melting point of the eutectic Cr-Zr interlayer was equal to 1332 • C [7,8], which resulted in melting the sample underneath the coating in the oxidation tests performed at 1330 and 1400 • C. Figure 14b shows some cracks in the surface "spikes" that are most likely formed due to outward release of Kirkendall cavities from the melted Cr-Zr region. The outer surface layer can move and liquid Cr-Zr region can be opened to a direct interaction with water steam due to the capillary effect of the liquid Cr-Zr interlayer and local swelling induced by a volume change.…”

Section: Steam Oxidation At 1250-1400 °Cmentioning

confidence: 99%

“…Steam oxidation of the Cr-coated E110 alloy samples with the ZrO 2 /Cr multilayers has another scenario at 1330-1400 • C. At the second stage of oxidation (Figure 15e), the Cr-Zr interlayers at the ZrO 2 /Cr multilayer interfaces could be melted when the temperature of the E110 alloy samples reached the melting point of the eutectic Cr-Zr phase (~1332 • C [7,8]). The liquid Cr-Zr regions caused a capillary effect, which resulted in displacing the coating on the alloy surface.…”

Section: Analysis Of the Oxidation Processmentioning

confidence: 99%

“…When the temperature of Zr-based elements reaches 900 • C, the phase transition of Zr alloys from the α (hexagonal closedpacked) to the β (body centered cubic) phase will occur. This causes the increase of a diffusion coefficient of Cr in Zr alloys that leads to a growth of a Zr-Cr eutectic layer with a melting temperature of ~1332 • C [7,8]. Thereby, much attention is warranted to find barrier materials for Cr coatings to prevent Cr-Zr interdiffusion at high temperatures.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Protective Cr Coatings with ZrO2/Cr Multilayers for Zirconium Fuel Claddings

et al. 2022

View full text Add to dashboard Cite

This article described the protective properties of Cr coatings with a barrier layer composed of ZrO2/Cr multilayers deposited onto E110 zirconium alloy. The coatings with a ZrO2/Cr multilayer thickness of 100, 250, and 750 nm and single-layer (1.5 µm) ZrO2 barrier were obtained by multi-cathode magnetron sputtering in Ar + O2 atmosphere. Then, cracking resistance and oxidation behavior were studied under conditions of thermal cycling (1000 °C) in air and high-temperature oxidation at 1200–1400 °C in a water steam. The role of the ZrO2/Cr multilayers and multilayer thickness on cracking resistance of the experimental coatings and oxidation resistance of the coated E110 alloy was discussed. It was shown that the coatings with more quantity of the ZrO2/Cr multilayers have higher cracking resistance, but such types of samples have a large amount of coating spallation under thermal cycling. The high-temperature steam oxidation (1200–1400 °C) demonstrated that interfaces of the ZrO2/Cr multilayers can act as a source of cavities formed by the Kirkendall mechanism that results in accelerating Cr–Zr interdiffusion for Cr-coated E110 alloy.

show abstract

Section: Steam Oxidation At 1250-1400 °Cmentioning

confidence: 99%

Section: Analysis Of the Oxidation Processmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Protective Cr Coatings with ZrO2/Cr Multilayers for Zirconium Fuel Claddings

et al. 2022

View full text Add to dashboard Cite

show abstract

“…In this paper, the experimental data show that the dense Cr coatings had the higher proportion of Cr transformed to Cr-Zr layer in comparison with the columnar ones. The phase composition of Zr alloy underneath the Cr coatings can strongly influence Cr-Zr interdiffusion kinetics as solubility and diffusion rate of Cr in β-Zr is higher than that of α-Zr [32]. Due to this, the samples with the columnar Cr coatings had less thickness of Cr-Zr layer as oxygen penetrates to the alloy and can stabilize the α-Zr phase that slows down Cr-Zr interdiffusion.…”

Section: 2mentioning

confidence: 99%

“…In view of higher solubility and diffusion rate of Cr in β-Zr than that of α-Zr [32], Cr would diffuse deeper in the Zr alloy when oxide layers in the Zr alloy are grown. When the samples began to cool down, the Zr-Cr liquid phase solidified and some blisters formed leading to the "crocodile skin" like morphology on the surface of the samples due to the volume changes associated with solid → liquid → solid reactions.…”

Section: High-temperature Oxidation In Steam At 1400 • Cmentioning

confidence: 99%