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  for Metal Finishing since 1989
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Blister Causes

2001

My company supplies die cast aluminum parts for chrome plating. The primary material is SAE 413. The parts are typically belt sanded to remove gates and feeders. Then they will go through a buffing process. Typically manual and also automated using many racks and robot buffers. They then get chrome plated. Note that copper buff is not used. It is a copper strike.

The primary defect present (attributed to the casting) is blisters. This was predominant on a single product and over the course of the past few months has expanded to virtually all of the products that are plated. I am curious what you think may be a list of causes for this particular defect.

Please note that the blisters do not always penetrate to the cast surface. Others do appear over small pits in the casting.

Additionally - is it possible to visually determine any of the causes you may list?

Thank you for your time and consideration.

Jay Standish
- Franklin Park, Illinois, USA