ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Diamond was coated on to cemented carbide substrate by microwave plasma CVD, in which nucleation control of diamond crystals was investigated under constant deposition conditions; total pressure 30 torr, CH4 flow rate 1 ml min−1, H2 flow rate 199 ml min−1 and microwave power 550 W. Nucleation tends to occur selectively on the edge part of WC grains of the cemented carbide substrate with coarse WC grain size of about 1 μm, where the nucleation density was 9×106 cm−2. The density increased to about 5×107 cm−2 when using a finegrained substrate (WC grain size ∼0.5 μm). A considerably enhanced nucleation was observed by introducing a number of fine microflaws on to the substrate surface. Microflawing treatment with diamond fine powder (grain size 0–1/4 μm) suspended in an ultrasonic cleaner bath was effective for increasing the diamond nucleation density up to 5×108 cm−2. The grain size of grown diamond crystals decreased with increasing microflawing time.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01184968
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