S.R. Lee
,
E.S.Byon and Y.-W. Seo 1)Korea Institnte of Machinery and Materials
,
Changwon 641-010
,
Korea 2)V & P International Co.
,
Ltd
,
705-9
,
Gozandong
,
Inchon 405-310
,
Korea Manuscript received 26 August 1996)
金属学报(英文版)
Cubic boron nitride (c-BN) films were successfully grown on Si(100)substrates by a helicon wave plasma-assisted chemical vapor deposition technique.The lower limits of rf substrated bias voltage and plasma density for formation of a single phase c-BN film were 350V and 4.5×10~(10) cm~(3),respectively. The grown c-BN films demonstrated a poor adhesion to the substrates. A postannealing treatment at 800℃ C in N_2 atmosphere was found very effective in relieving the compressive stress in the films which were thereby stabilized to improve the adhesion.
关键词:
:cubic boron nitride
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null
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null
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S. X. Wang
,
D. S. Zheng and Y. L. Liu 1) Department of Material Engineering
,
Luoyang Institute of Technology
,
Luoyang 471039
,
China 2) Luoyang Copper (Group) Co.
,
Ltd
,
Luoyang
,
China
金属学报(英文版)
The model established in this paper for calculating the unsteady temperature field, in which physical parameters varies with temperatures, is simplified as compared with the classical one by defining the heat conductivity as function of temperature and dealing with the latent heat of phase transformation and boundary conditions. The results show that the probability of absolute error less 2℃ between the calculated and measured values in temperature field calculation reaches above 80%.
关键词:
temperature field
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null
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S. X. Wanng
,
D. S. Zheng
,
Y. L. Liu 1) Department of Material Engineering
,
Luoyang Institute of Technology
,
Luoyang 471039
,
China 2) Luoyang Copper (Group) Co.
,
Ltd
,
Luoyang
,
China
金属学报(英文版)
As far as the accuracy of calculating unsteady temperature field is concerned, it is very important to find the accurate physical parameters such as specific heat, thermal conductivity, latent heat of phase transformation and surface heat flux. The model for calculating H and Q is established in this paper. The measurement methods and data processing for physical parameters such as volume specific heat C, thermal conductivity k, volume latent heat of phase transformation c1 and surface heat flux are introduced The physical parameters of 1Cr18Ni9Ti and 45 steels and the surface heat flux for 1 Cr18Ni9Ti probe cooled in water,10% NaCl water and oil with different temperatures are measured, respectively. These data show that the probability of absolute error less than 2* C between the calculated and measured values in temperature field calculation reaches above 80% if using the above physical parameters, which provides a reliable technology basis for precise calculation of temperature field.
关键词:
unsteady temperature field
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