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Session:

1B - Temperature I 

Date & Time:

Monday August 7, 10:45 AM - 12:15 PM

Paper Title:

Study of the influence of inducing nucleation on the performance of the freezing temperature plateau of fixed point cells 

 

 

Speaker:

Rong Ding, Ph.D  

CoAuthors:

Mingjian Zhao, Deming Chen 

Speaker Info

Company:

Fluke Hart Scientific

Department:

Primary Standards

Address:

799 E Utah Valley Drive
American Fork, UT, 84003, United States

Phone:

801-763-1600

Email:

rong.ding@hartscientific.com 

 

 

Abstract:

Experimental research was carried out to investigate the influence of the technique of inducing nucleation on the performance of the temperature plateau during the realization of metal freezing points of fixed-point cells. Different induction techniques were studied in the experiments. The experimental results show that the induction methods and the induction time significantly affect the performance of the freezing temperature plateau, especially at the beginning of freezing. Insufficient induction removes too little of the latent heat released by the start of the freeze and causes delayed settling at the beginning of the plateau. Excessive induction results in too much of the material freezing and reduces the length and quality of the plateau. The induction method and induction length should be carefully chosen based on the characteristics of the particular fixed-point cell in order to provide sufficient cooling for nucleation and obtain the ideal freezing temperature plateau. The optimal induction techniques derived from the research were used in the testing of indium, tin, zinc, aluminum, and silver fixed-point cells at Fluke Hart Scientific. The consequent freezing plateaus obtained in these tests are presented here. 

 

 

 

 

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