Nanocomposite coating

Why in news?

• ARCI scientists develop friction-reducing nanocomposite coatings to increase device life.

About Nanocomposite coating

• Several aerospace, defence, automobile, space devices need to reduce friction, wear, and tear to enhance the life of components. The usual route taken is to lubricate these dynamic systems, which add to the cost, complexity, and weight of these systems.
• A group of scientists at the International Advanced Research Centre for Powder Metallurgy & New Materials (ARCI), an autonomous R&D center of the Department of Science & Technology (DST) have developed a process for size-selective deposition of nanocomposite coatings which can reduce friction of these dynamic systems.
• Nanocomposite coatings are formed by mixing two or more dissimilar materials at nanoscale to improve the physical, chemical and physicochemical properties of the new materials.
• The scientists have found that nickel tungsten-based coatings with impregnation of particular sized Silicon Carbide (SiC) submicron particles using an economical and straightforward pulsed electroplating or electrodeposition process can provide an excellent combination of wear and corrosion resistance with the low friction coefficient and good oil retention capacity.
• The coatings developed by the ARCI group reduced friction more and could withstand corrosion due to salt spray better than many similar wear-resistant coatings available in the market.
• Nanocomposite coatings with hard particles inside a tough matrix result in the best combination of wear resistance and reduced friction.
• However, the size of reinforcement particles is a critical factor in deciding the friction characteristics. Too much variation in the size of reinforcement particles in composite coating results in premature failure of the coating due to stress concentration.

What is Nanocomposite?

• Nanocomposite is a multiphase solid material where one of the phases has one, two or three dimensions of less than 100 nanometers (nm) or structures having nano-scale repeat distances between the different phases that make up the material.
• The idea behind Nanocomposite is to use building blocks with dimensions in nanometre range to design and create new materials with unprecedented flexibility and improvement in their physical properties.

Prelims Question

Q.With reference to Nanocomposite coatings, which of the following statements is/are correct?
1. Nanocomposite coatings are formed by mixing two or more dissimilar materials at nanoscale
2. Nanocomposites can lead to new materials with unprecedented flexibility and improvement in their physical properties
Select the correct answer using the code given below:
a. 1 only
b. 2 only
c. Both 1 and 2
d. Neither 1 nor 2

Answer to the Prelims Question