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Zinc plated piston compatibility with aluminum body

We are using in the car rear brake assembly aluminum as a w/c material, and for steel piston using Cr3 zinc plating. Will this combination work?

Anup Bhawtankar
Product designer - Pune, Maharashtra, India
October 27, 2010

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Dear Mr Anup,

What is it that you want to make work in this combination?
Corrosion compatibility - wear resistance - Please post a picture of the assembly if possible to merit a better response?

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

November 24, 2010

Actually in the brake wheel cylinder assembly we are using a pistion with Zinc CR3 plating and its matching bore surface is made up of Aluminum with anodised bore. I want to know whether this combination will work OR not?

Anup Bhawtankar
Automobile - Pune, Maharashtra, India
December 3, 2010

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Dear Mr Anup,

Your designers must have planned a life cycle for this assembly? Normally these pistons are never zinc plated since they are supposed to take wear and tear and zinc is too soft for such a critical application. Electroless Nickel is normally used - if zinc was designed in the first place it may be worthwhile looking at harder deposits such as zinc nickel plating as an option.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

December 4, 2010