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If you are confused by the available grades of Neodymium or curious about how a grade is assigned to a particular Neodymium alloy, this post is for you.
N35, ND-35, and ND-3512 are all the same “Grades.” They represent a neo magnet alloy which has an Energy Density (Maximum Energy Product) of 35 and has an Intrinsic Coercive force of 12 kOe. The 12kOe results in a maximum operating temperature for the magnet of 80°C. (The actual maximum Operating Temperature is geometry dependent and the 150°C is used here for illustrative purposes.)
N45SH, ND-45SH, and ND-4520 are all the same grade of Neo alloy. This notation represents a neo magnet alloy which has an Energy Density (Maximum Energy Product) of 45 and has an Intrinsic Coercive Force (Hci) of 20 kOe. The 20kOe is indicated in the grade notation by the “SH” suffix and results in a maximum operating temperature for the magnet of 150°C. (The actual Maximum Operating Temperature is geometry dependent and the 150°C is used here for illustrative purposes.)
Neo Grade Explanation
As described above, a Neodymium magnet’s “Grade” is derived from the Energy Density (Maximum Energy Product) and some indicator of the Neodymium alloy’s ability to operate at elevated temperatures. Knowing the grade is not sufficient to predict a magnet alloy’s performance in an application. The Neo magnet’s grade will also have several other characteristics which are used to judge the magnet’s performance in an application. Unless the application is at ambient room temperature, the magnet has a Magnetic Length / Diameter ratio > 0.7, and there is no external demagnetizing fields, a performance review should be executed. Please engage a Dura application representative for assistance when selecting a Neo grade for your application.
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