Ezperimental Research on the Melting Behavior of Pt-C Eutectic Fized Point Affected by Thermal History
Previous research indicates that melting behavior of the metal carbon eutectic fixed points (MCs) can be affected to different extent by thermal history such as previous freezing rate of the cooling process and the pre-annealing condition. This paper deals with the experimental research on the melting behavior of different structural Pt-C cells affected by the thermal history. Two Pt-C fixed point cells were chosen, the sleeve type cell (named Pt-C 2#) and the two layer C/C sheet+sleeve type cell (named Pt-C 4#). Least square fit of 5 order polynomials were employed to characterize the melting plateaus and to obtain TE (the point of inflection of the melting plateau). The effect of thermal history on the subsequent melting plateaus was distinct for the different structural Pt-C cells, for the sleeve type cell the prefreezing rate effect was more remarkable. The different structure might account for the variation. The pre-freezing rate varied from (Tw5) ℃, (TE -10) ℃, (TE -20) ℃ to (TE -40) ℃, and the subsequent melting rate was set at the same (TE+20) ℃, the maximal change of the melting temperature was 43 mK for the sleeve type cell and 12mK for the two layer C/C sheet+sleeve type cell. The 4 h pre-annealing at (TE -20) ℃ flattened and prolonged the melting plateau for both the two type cells, with TE increased 45inK for sleeve type cell and no obvious change for thetwo layer C/C sheet+sleeve type cell.
Metrology Radiation thermometry Metal-carbon eutectic Fized point Pt-C Thermal history
DONG Wei WANG Tie-jun BAI Cheng-yu DUAN Yuan-yuan
National Institute of Metrology, Beijing 100013, China Key Laboratory for Thermal Science and Power National Institute of Metrology, Beijing 100013, China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Depart of Thermal
国际会议
2008年国际温度与热物性测量会议(TEMP BEIJING 2008)
北京
英文
129-133
2008-10-20（万方平台首次上网日期，不代表论文的发表时间）