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"Process Capability of Adhesion Tape Test"

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2005

Hi

I am a new to the eletroplating industry. We use the tape test with 5 different grades 1 to 5 to help in deciding whether Zn adhesion is good or bad on the plate. I guess this is a pure attribute type of data that we will end up with. Hence I was wondering how to calculate the process capability for this type of data.

Is there a specific formula or method to calculate the Cp or the Cpk for attribute type of data..

If anyone could help .it will be great

Regards

Sid Saravanan
Eletroplating - Toledo, Ohio

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2005

Dear Friend,

Generally when you do the tape test you can take 1.00" X 1.00" square area, place your cuts @ 0.100" apart which will give you 100 boxes. Do peel test and approximately calculate area with plating peeled off v/s area plating is still adhered to. This is now your variable.

Calculate your Cp & Cpk. Based on # of Squares or to be more precise sq. inch area.

Shah Gaurav
- Sunnyvale, California