2007 Fiscal Year Final Research Report Summary
Analysis of super-low friction mechanisms of carbon nitride in nitrogen gas lubrication and development of low frictiioon tribo-system
Project/Area Number |
18360075
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Design engineering/Machine functional elements/Tribology
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Research Institution | Tohoku University |
Principal Investigator |
ADACHI Koshi Tohoku University, Tohoku University, Graduate School of Engineering, Associate Professor (10222621)
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Co-Investigator(Kenkyū-buntansha) |
KATO Koji Tohoku University, 名誉教授 (50005443)
KUBO Momoji Graduate School of Engineering, 大学院・工学研究科, Professor (90241538)
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Project Period (FY) |
2006 – 2007
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Keywords | Super-low friction / Carbon nitride / Nitrogen gas / Running-in / Silicon nitride / Graphite / Atmospheric condition / Dry air |
Research Abstract |
In case of carbon nitride coatings, super-low friction coefficient on the order of 0.001 is achieved in sliding against itself or silicon nitride in the stream of nitrogen gas. In this study, effect of exposure condition after deposition of carbon nitride coatings and running-in process on friction properties of carbon nitride coatingssliding against itself or silicon nitride in nitrogen gas is investigated to clarify the super-low friction mechanisms and to develop low friction system with carbon nitride coatings. Furthermore, possibility of further lower friction and necessary surface conditions for stable and low friction coefficient as low as 0.03 are investigated Following are main results of this research. (1) The average values of friction coefficient of carbon nitride coating sliding against silicon nitride ball in nitrogen gas condition varied from 0.003 to 0.6 by exposure condition after deposition of the carbon nitride coating. (2) When carbon nitride coatings are exposed to oxygen gas first for 100 seconds after deposition of carbon nitride coatings, and then exposed to ambient air with 40-60% RH for 30 minutes, the friction coefficient in nitrogen gas condition shows as low as 0.003. (3) By introducing 500 cycles of pre-sliding in ambient air, friction coefficient reduces from 0.07 to 0.004 and specific wear rate of ball also reduces from 1.0×10^<-7>mm^3/Nm to 1.0×10^<-10>mm^3 on sliding of carbon nitride against itself in nitrogen gas stream. (4) Friction coefficient of lower than 0.01 is observed in nitrogen gas stream by giving optimum range of 50 to 1,000 cycles of pre-sliding in ambient air.
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Research Products
(23 results)