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Magnetic Permeability of stressed SS 4

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Ron07663

Electrical
Aug 7, 2001
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I am designing a deep drawn SS can to be a shield for a magnetic sensor. We need the relative permeability of the shield to be as close to 1 as possible so as to not interfere with the sensor. Annealed 304 or 316 SS should be on the order of 1.0 to 1.02. What can I expect the permeability value to be for stressed 304 and 316?
 
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We ran sample parts out of our deep draw tool of both 316 SS and 305 SS. The 305 was selected for Ni content of 12% or greater.
The 316 parts had a measured permeability of 1.15 right out of the tool and 1.0003 after solution anneal.
The 305 parts measured 1.003 right out of the tool.
Our specification required 1.05 MAX. So, if 316 were used, we would require a post draw anneal.

Thanks again for everyones help with this.
 
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