Guide to N35 Neodymium Magnets Size Shape and Force

Have you ever wondered how much force a small magnet can actually generate? Among various magnetic materials, N35 neodymium magnets stand out for their exceptional cost-performance ratio, making them one of the most widely used options in both industrial and everyday applications. However, when faced with N35 magnets of different sizes and shapes, many users struggle to accurately assess their adhesive force. This article explores the magnetic properties of N35 neodymium magnets and examines the key factors that determine their holding power.

Neodymium magnets, as representatives of rare-earth permanent magnetic materials, are renowned for their extremely high magnetic energy product and coercivity. N35 is a common grade of neodymium magnet where "N" stands for the neodymium-iron-boron material, and "35" represents its maximum theoretical magnetic energy product in MGOe (Mega-Gauss Oersteds). The magnetic energy product is a crucial indicator of a magnet's performance—the higher the value, the greater the magnetic energy stored in the same volume, resulting in stronger magnetic force.

The popularity of N35 magnets stems from their optimal balance between magnetic strength and cost. Compared to higher-grade neodymium magnets, N35 meets most application requirements while remaining more competitively priced. This makes N35 magnets widely used in motors, sensors, speakers, medical equipment, consumer electronics, and even common items like toys and decorative crafts.

A magnet's adhesive force, also called pull force or breakaway force, refers to the maximum weight it can hold when pulled vertically. This is a direct measure of a magnet's strength and one of the most critical parameters users consider when selecting magnets.

However, accurately calculating the adhesive force of N35 magnets isn't straightforward. This is primarily because multiple factors influence a magnet's holding power, including:

• Magnet size and shape: Larger magnets with optimized shapes generally provide stronger adhesive force. For instance, among magnets of the same material and grade, thicker cylindrical magnets typically outperform thinner ones.
• Magnet grade: Higher-grade magnets with greater magnetic energy products deliver stronger adhesive force. While N35 is one grade of neodymium magnet, higher grades like N42 or N52 offer significantly greater holding power.
• Material and thickness of the attracted object: Magnets only adhere to ferromagnetic materials like iron, nickel, or cobalt. The composition and thickness of the attracted material affect the adhesive force—for example, magnets hold pure iron more strongly than alloy steel.
• Contact area and air gap: Greater contact area between the magnet and attracted object increases adhesive force. Any air gap (from paint, dust, etc.) weakens magnetic flux and reduces holding power.
• Operating temperature: Magnetic force decreases as temperature rises. When exceeding the magnet's Curie temperature, it loses its magnetism entirely. Thus, temperature stability must be considered for high-temperature applications.

Given the complexity and number of influencing factors, theoretical calculations often fail to predict actual adhesive force accurately. In practical applications, experimental testing typically determines a magnet's holding power.

To help readers better understand N35 magnets' adhesive force, we've compiled reference data for common sizes and shapes. Note that these values are approximate, as actual results may vary based on testing conditions and environment.

The table demonstrates that for magnets of the same shape, larger dimensions yield stronger adhesive force. For example, a 20mm diameter, 3mm thick N35 disc magnet holds approximately 3.6kg, while reducing the thickness to 2mm decreases the force to 2.3kg—showing thickness significantly affects disc magnets' performance.

Shape also influences adhesive force. Similar-sized rectangular and square magnets exhibit different holding power because their magnetic flux distributions vary by shape.

When selecting N35 magnets for real-world use, consider not just adhesive force but also size, shape, operating temperature, and cost. Applications requiring strong holding power may need larger magnets or higher-grade neodymium options, while space-constrained scenarios demand careful balance between size and strength.

Additionally, magnet protection matters. Neodymium magnets oxidize and corrode easily, so avoid exposure to moisture and corrosive substances. For long-term use, protective coatings can extend lifespan.

With their outstanding cost-performance ratio, N35 neodymium magnets serve diverse applications across industries. Understanding their magnetic properties and the factors affecting adhesive force helps users select and implement magnets effectively for various needs.