Effects%20of%20target%20current%20on%20the%20mechanical%20properties%20of%20Cr-C%20coatings%20by%20using%20the%20Unbalanced%20Magnetron%20Sputtering

1
Effects of target current on the mechanical
properties of Cr-C coatings by using the
Unbalanced Magnetron Sputtering
Professor Dr. Yu-Sen Yang
SpeakerJia-Hau Lin Date 2011.05.20
2
Outline

• Introduction
• Experiment
• Results and discuss
• Conclusion

3
Introduction

• 1.The chromium carbide (Cr-C) films have
  excellent properties including chemical
  stability, oxidation resistance, low coefficient
  of friction and wear resistance.
• 2. The excellent anti-wear performance of Cr-C
  films can be attributed to the large content of
  carbide.
• 3. Cr-C coatings have been known to protected
  tools which may be damaged by high thermal load
  (high cutting speed).

4
Experiment (equipment)
Equipment Unbalance magnetron sputtering Substrate high speed steel(SKH51)

5
Experiment (parameter)
1.Ar cooling time after deposition 20 Min
2.Substrate bias -100 V
3.Chromium target current 1A,2A,3A,4A,5A,6A
4.C2H2 flow rate ratio 30
5.Ion bombardment voltage -300 V
6.Work distance 13 cm
7.Frequency of substrate 100 KHz
8.Rotation speed of substrate holder 5rpm
???????,2010,?????????Cr-C?????????,??????????,??
??
6
Experiment (Properties test )

• 1.Component Analysis EDS
• 2.Morphology FE-SEM
• 3.Microstructure Raman Analysis
• 4.Friction coefficient Ball-on-disc

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Experiment (Properties test )

• 5.Wear rate estimation Calculated after
  measuring wear
• track
  by Alpha-step
• (1)Alpha-Step????????
• (2)??????????

V??,R????,A???????
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Results and discuss (Component Analysis)
Cr??? Cr( at.) C ( at.)
1 A 5.8 94.2
2 A 22.2 77.8
3 A 47.3 52.7
4 A 59.3 40.7
5 A 63.8 36.2
6 A 68.9 31.1
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Results and discuss( Friction coefficient test)
1A 2A 3A 4A 5A 6A
0.29 0.22 0.39 0.61 0.78 0.66
Against ball Loading Rotation diameter Rotation rate Length
Cr ball 0.5kg 20mm 286rpm 1000m
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Results and discuss (Wear rate)
??mm3?N-1?m-1
1A 2A 3A 4A 5A 6A
610-6 2410-6 14210-6 27010-6 30310-6 42310-6
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Results and discuss (friction coefficient)
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Results and discuss (Wear rate)
13
Results and discuss
1A
6A
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Results and discuss(Raman)
D band 1350 cm-1 G band1580 cm-1
?????? ??????(cm-1)
???? 13321334
????(C12) 1323
?? 1350 15801600
????(C13) 1290
????? 1332
????(a-C) ????? 1350?? 1580??
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Conclusions

• The experimental results show the carbon content
  in Cr-C films increase with decreasing target
  current when target current decrease from 6A to
  1A,the carbon content increase from31.1 at. to
  at 94.2 at. .
• The friction coefficient of films decrease from
  0.66 to 0.22 and the wear rate is reduced from
  423?10-6 (mm3?N-1?m-1) to 6?10-6 (mm3?N-1?m-1)
  when the current reduced from 6A to 1A.
• The lowest wear rate is 6?10-6 (mm3?N-1?m-1) at
  traget current 1A
• The lowest friction coefficient is 0.22 at traget
  current 2A
• The excellent anti-wear performance of Cr-C films
  can be attributed to the large content of carbide.

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• The reasons for a low coefficient of friction is
  the formation of solid solution carbon in the
  diamond-like carbon film in the crystal
  structure, which could effectively reduce wear
  and promote the wear resistance characteristics.

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• The End