Thermocouple observations of melting and freezing plateaus for metal-carbon eutectics between the copper and palladium points

被引：38

作者：

Yamada, Y ^{[1
]}

Sakuma, F ^{[1
]}

Ono, A ^{[1
]}

机构：

[1] Natl Res Lab Metrol, Tsukuba, Ibaraki 3058563, Japan

来源：

METROLOGIA | 2000年 / 37卷 / 01期

关键词：

Carbon - Cooling - Crucibles - Eutectics - Freezing - Heating - High temperature operations - Iron alloys - Melting - Nickel alloys - Palladium alloys;

D O I：

10.1088/0026-1394/37/1/10

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

Melting and freezing plateaus were observed with type-Ii thermocouples for the metal-carbon eutectics Pd-C, Ni-C, and Fe-C. For Pd-C, no apparent difference between the melting and freezing temperatures was observed at a heating/cooling rate of 3 degrees C/min. For Ni-C, the difference was 0.4 degrees C, and for Fe-C, 1.6 degrees C. The freezing temperature for Fe-C showed dependence on cooling rate, and the difference between the melt and the freeze decreased to 0.5 degrees C, though still significant, at a heating/cooling rate of 0.1 degrees C/min. The melting temperatures, measured with type-R thermocouples, were 1491 degrees C, 1329 degrees C, and 1153 degrees C, respectively, for Pd-C, Ni-C, and Fe-C eutectics, which agreed to within 1 degrees C with the values previously measured by radiation thermometers or the literature values. The crucibles, being made from graphite, were able to withstand heating cycles without breaking. The three metal-carbon eutectics, with melting temperatures between the copper point and the palladium point, are potentially useful practical reference points for calibration and evaluation of high-temperature thermocouples.

引用

页码：71 / 73

页数：3

共 4 条

[1]

EDLER F, 1997, P TEMPMEKO 96 6 INT, P183

[2]

MASSALSAKI BT, 1986, BINARY ALLOY PHASE D, V1

[3] Radiometric observation of melting and freezing plateaus for a series of metal-carbon eutectic points in the, range 1330°C to 1950°C [J].