A Study of the Metal Carbide-Carbon Peritectic Phase Transition for the Cr-C System

Yamada, Yoshiro; Wang, Y.; Zheng, Wenjuan; Sasajima, N.

doi:10.1007/s10765-007-0297-5

Cited by 6 publications

(17 citation statements)

References 6 publications

(10 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The plateau durations of the two transitions were clearly related to the ratio of volume of the two domains. In this paper, we report experimental results of the melting plateau's dependence on material purity, thermal history, and melting rate and discuss the fixed-point performance in relation to the investigations reported in [2].…”

Section: Introductionmentioning

confidence: 88%

“…The chromium powders were mixed with graphite powders of 99.9999% nominal purity (supplied by Johnson & Matthey). The crucible design is the same as in [2]. The graphite crucibles were purified to better than 99.9995% purity by the manufacturer (SGL Carbon).…”

Section: Fixed-point Cellsmentioning

confidence: 99%

“…The graphite crucibles were purified to better than 99.9995% purity by the manufacturer (SGL Carbon). The filling of the cells was performed according to the non-porous filling method without the C/C sheet wick, as described in [2]. …”

Section: Fixed-point Cellsmentioning

confidence: 99%

“…In another paper in these proceedings by the authors, the Cr 3 C 2 -C peritectic point is studied for the purpose of understanding the peritectic reaction involved [2]. A third paper describes the investigation of the WC-C peritectic point (2,749 • C) [3].…”

Section: Introductionmentioning

confidence: 99%

“…This is an indication that there is still a liquid phase remaining even when the freezing at the peritectic phase transition appears complete. In [2], microstructure analysis showed two distinct domains in the ingot, one rich in carbon and the other rich in chromium. Comparison with the observed plateaux indicates that the carbon-rich portion is the solid formed when the Cr 3 C 2 -C peritectic freezes, and the chromium-rich part forms when the Cr 7 C 3 -Cr 3 C 2 eutectic freezes.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Experimental Investigation of the Cr3C2–C Peritectic Fixed Point

2008

Self Cite

View full text Add to dashboard Cite

The Cr 3 C 2 -C (1,826 • C) peritectic point was investigated for its performance as a high-temperature fixed point. Dependence on the impurity content was observed, although it was less severe for the higher of the two equilibrium temperatures obtained with the same cell, the Cr 3 C 2 -C peritectic point, than for the lower, the Cr 7 C 3 -Cr 3 C 2 eutectic point. Thermal history had an effect on the melting plateau duration, but not on the point-of-inflection temperature nor on the melting range. The melting rate had no apparent effect. The repeatability evaluated as the standard deviation of the repeated melting plateaux within a day was 20 mK for the Cr 3 C 2 -C peritectic point, while for the Cr 7 C 3 -Cr 3 C 2 eutectic point, this was 210 mK. For both the Cr 3 C 2 -C peritectic and the Cr 7 C 3 -Cr 3 C 2 eutectic, the freezing plateaux often showed deep supercools, which made them unsuitable for use. The observed good repeatability shows the peritectic-point performance to be comparable to the best MC-eutectic high-temperature fixed points investigated so far. The insensitivity to thermal history constitutes an important and practical advantage. The low price of chromium is a clear benefit as compared to Pt-C (1,738 • C) or Ru-C (1,953 • C) eutectic points, the M-C eutectic points in this temperature range.

show abstract

Section: Introductionmentioning

confidence: 88%

Section: Fixed-point Cellsmentioning

confidence: 99%

Section: Fixed-point Cellsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Experimental Investigation of the Cr3C2–C Peritectic Fixed Point

2008

Self Cite

View full text Add to dashboard Cite

show abstract

Investigation of TiC–C Eutectic and WC–C Peritectic High-Temperature Fixed Points

Sasajima¹,

Yamada²

2008

Int J Thermophys

View full text Add to dashboard Cite

TiC-C eutectic (2,761 • C) and WC-C peritectic (2,749 • C) fixed points were investigated to compare their potential as high-temperature thermometric reference points. Two TiC-C and three WC-C fixed-point cells were constructed, and the melting and freezing plateaux were evaluated by means of radiation thermometry. The repeatability of the TiC-C eutectic within a day was 60 mK with a melting range roughly 200 mK. The repeatability of the melting temperature of the WC-C peritectic within 1 day was 17 mK with a melting range of ∼70 mK. The repeatability of the freezing temperature of the WC-C peritectic was 21 mK with a freezing range less than 20 mK. One of the TiC-C cells was constructed from a TiC and graphite powder mixture. The filling showed the reaction with the graphite crucible was suppressed and the ingot contained less voids, although the lack of high-purity TiC powder poses a problem. The WC-C cells were easily constructed, like metal-carbon eutectic cells, without any evident reaction with the crucible. From these results, it is concluded that the WC-C peritectic has more potential than the TiC-C eutectic as a high-temperature reference point. The investigation of the purification of the TiC-C cell during filling and the plateau observation are also reported.

show abstract

New Filling Technique and Performance Evaluations of the Cr3C2−C Peritectic Fixed Point

Sasajima¹,

Lowe

Bai³

et al. 2011

Int J Thermophys

Self Cite

View full text Add to dashboard Cite

The Cr 3 C 2 -C peritectic fixed point was investigated to test its capability to serve as a practical high-temperature fixed point. An improved filling technique where C/C sheet works as a wick and graphite paper as a hopper was applied successfully, and the long-term stability of the peritectic cell was evaluated by means of radiation thermometry. The repeatability of the melting point in one day was 7 mK with a melting range of approximately 100 mK. The cell was aged for 7 days, and the evaluated 56 melting temperatures during this period all fall within 90 mK, with a standard deviation of 19 mK. X-ray transmission photos showed that the ingot was filled uniformly in the crucible. After the evaluation of long-term stability, no clear degradation of the ingot shape and no leakage of molten metal were observed. From these results, it can be concluded that the Cr 3 C 2 -C peritectic cell has good stability and robustness, and the new filling technique was established. The impurity effect on the Cr 3 C 2 -C peritectic cell was also investigated by adding tungsten powder to another cell as the impurity component. After the observation of melting and freezing plateaux, the cell was cut in half to analyze the microstructure by means of electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). The high concentration of impurity was observed in the area of the chromium-rich domain (eutectic mixture of Cr 7 C 3 and Cr 3 C 2 ), which suggests that impurities were rejected from the Cr 3 C 2 peritectic phase during the peritectic freezing and were accumulated in the Cr 7 C 3 -Cr 3 C 2 eutectic phase. This explains why the impurity effect is more severe for the Cr 7 C 3 -Cr 3 C 2 eutectic point than for the Cr 3 C 2 -C peritectic point.

show abstract

A Study of the Metal Carbide-Carbon Peritectic Phase Transition for the Cr-C System

Cited by 6 publications

References 6 publications

Experimental Investigation of the Cr3C2–C Peritectic Fixed Point

Experimental Investigation of the Cr3C2–C Peritectic Fixed Point

Investigation of TiC–C Eutectic and WC–C Peritectic High-Temperature Fixed Points

New Filling Technique and Performance Evaluations of the Cr3C2−C Peritectic Fixed Point

Contact Info

Product

Resources

About