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iTSSe TSS
A D V A N C E D M A T E R I A L S & P R O C E S S E S | J U L Y / A U G U S T 2 0 1 5
4 8
iTSSe
TSS
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JTST HIGHLIGHTS
modulus of microhardness, and Weibull modulus of elastic
modulus reach theirmaximumat the central position (175 µm)
on the coatings’ cross-section. The Weibull modulus of micro-
hardness reveals similar values throughout the thickness, and
the Weibull modulus of elastic modulus shows higher values
on the top surface compared to the cross-section.
“PREPARATION AND ABLATION PROPERTIES
OF Y2SiO 5 COATING FOR SiC COATED C/C COM-
POSITES BY SUPERSONIC PLASMA SPRAYING”
Jia-Ping Zhang, Qian-Gang Fu, Lei Zhuang,
He-Jun Li, and Can Sun
Y2SiO5 coating was prepared on the surface of SiC coat-
ed C/C composites by supersonic plasma spray at powers of
35, 40, 45, and 50 kW. The microstructures and phase com-
positions were characterized by scanning electron microsco-
py and x-ray diffraction, respectively. Coating roughness was
measured by a confocal laser scanning microscope. Bonding
force between the Y2SiO5 outer coating and SiC inner coat-
ing was measured by a scratch tester. Results show that the
Y2SiO5 coating prepared at spray power of 45 kW possesses
the biggest deposition rate, minimum surface roughness
(Ra=11.12 μm), and maximum bonding force (up to 28 N). The
linear and mass ablation rates of the Y2SiO5 coating prepared
Hydroxyapatite powders: Particles image.
Effects of indentation angle, testing direction, measurement
location, and applied load on the microhardness and elastic
modulus were investigated. The variability and distribution
of the microhardness and elastic modulus data were statisti-
cally analyzed using the Weibull modulus distribution. Results
indicate that the dependence of microhardness and elastic
modulus on the indentation angle exhibits a parabolic shape.
Dependence of microhardness values on the indentation an-
gle follows Pythagoras’s theorem. Microhardness, Weibull