NdFeB magnet is the strongest commercial permanent magnet, the magnetic strength is very high, so it is widely used in industry, electronics, motors and daily life, this article will introduce you to 40mm neodymium magnets how strong unfolding introduction.
Neodymium magnets, especially those with a size of 40mm, have strong magnetic strength even at thin thicknesses, which may vary depending on the actual size, grade (e.g., N35, N42, N52, N54), and so on.
Double-Sunk Hole Rectangular Neodymium Magnet

Generally speaking, the higher the grade of magnetization of a neodymium magnet, the stronger its magnetic force will be. For example, an N54 grade neodymium magnet, which is one of the highest grades of neodymium magnets available on the commercial market today, is much stronger than an N35 grade magnet. A typical 40mm diameter neodymium magnet a few millimeters thick, even with an N42 rating, is easily able to attract ferrous objects hundreds of times over its own weight.
Below are several common shapes of 40mm neodymium magnet gauss and its pulling force data, for reference only, subject to actual.
N35 grade round neodymium magnets 40mm x 5mm, with an apparent magnetic strength of about 3600 gauss and a vertical pulling force of over 10kg.
N52 grade round neodymium magnets 40x10mm can hold 2kg of iron vertically across the palm of 1 hand.
N45 grade neodymium magnet block 40x20x10mm, surface magnetic strength about 5000 gauss, tensile strength about 17.2kg.
A ring-shaped NdFeB magnet with an outer diameter of 40mm, an inner diameter of 20mm, a thickness of 5mm, and a magnetization grade of N42 has a theoretical pulling force of about 10kg under ideal conditions (i.e., adsorption on a smooth, uncoated steel surface).
For neodymium magnet assemblies with steel shells, the pulling force exceeds 20kg for 40mm diameter.
In actual use, the actual pulling force may be reduced due to factors such as environmental conditions, material of the adsorbed object and surface condition. In addition, magnets produced by different manufacturers, even with the same specifications, may differ in performance due to differences in production processes.
Our company is a magnet direct manufacturer, we can customize 40mm rare earth neodymium magnets of various shapes for you, no matter the size is thin or thick, big or small, simple or complex, all can be processed, welcome to inquire and buy.
40mm Rare Earth Neodymium Magnet Sample
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