Lanthanum Phosphate Based Ceramic Composite Coatings for High Emissivity Applications

Authors

  • Aniantony  Department of Materials Science and Technology, NIT Calicut, Kerala, India
  • Ananthakumar Solaiappan  Department of Materials science and technology, NIEST-CSIR, Trivandrum, , India

Keywords:

Lanthanum Phosphate, Thermal Conductivity, Aluminium Phosphate, Orthophosphoric Acid, LaPO4, NH3, Aluminum and Alumina

Abstract

Lanthanum phosphate, a soft ceramic material, with low thermal conductivity, high melting point and high temperature phase stability is a good candidate for getting a tough ceramic coating for use at high temperatures. In this work, a novel high emissivity ceramic coating based on lanthanum phosphate ceramic pigment was developed. Initially, a black pigment based on lanthanum phosphate with an L* value of 34.71 was obtained through solid state reaction by suitable pigment addition and subsequent high temperature firing. This pigment was then brush painted on to alumina and stainless steel substrates using aluminium phosphate and sodium silicate inorganic binders and fired at suitable temperatures for setting of coatings. The average spectral emissivities of the coatings in the wavelength range 0.7?m to 2.5?m was above 0.9. The emissivity variation with porosity of substrate, temperature, roughness of coating and viscosity of binders was studied for getting an optimised coating with high emissivity.

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International Journal of Scientific Research in Science, Engineering and Technology

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Published

2017-04-30

Issue

Volume 3, Issue 4, March-April-2017

Section

Research Articles

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This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

[1]
Aniantony, Ananthakumar Solaiappan, " Lanthanum Phosphate Based Ceramic Composite Coatings for High Emissivity Applications, International Journal of Scientific Research in Science, Engineering and Technology(IJSRSET), Print ISSN : 2395-1990, Online ISSN : 2394-4099, Volume 3, Issue 4, pp.26-37, March-April-2017.