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Q1. Anodising is

 Q1. What is Anodising 

(A) a process of coating of zinc by hot dipping 

(B) a zinc diffusion process

(C) a process used for making thin phosphate coating on steel to act as a base or primer for enamels and paints

(D) an oxidizing process used for aluminum and magnesium articles

Ans (D) an oxidizing process used for aluminum and magnesium articles 

*Anodising:- Anodising is an electrolytic process for producing thick oxide layer(coating), usually on aluminium and its alloys. The oxide layer is typically 5 to 30 micro meter in thickness and is used to give improved surface resistance to wear and corrosion,  or as a decorative layer.



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