Since their introduction in the 1980s, sintered NdFeB permanent magnets have been widely used in automotive, wind power, aerospace, defense, and many other industries due to their outstanding magnetic performance. In recent years, rapidly growing demand from applications such as wind turbines and new energy vehicles has placed increasingly higher requirements on the coercivity and thermal stability of NdFeB magnets. Because the magnetocrystalline anisotropy field of the Dy₂Fe₁₄B phase is significantly higher than that of Nd₂Fe₁₄B, and its Curie temperature

The corrosion resistance of sintered NdFeB permanent magnets depends not only on the corrosion behavior of the base material itself, but also on the type of surface coating, coating thickness, and coating process used. The table below summarizes the typical exposure times at which corrosion may occur for sintered NdFeB samples under three common environmental test conditions. Within these specified test durations, the coating must not exhibit any visible defects such as blistering, peeling, rusting, or powdering. Slight color changes

Many customers ask EPI how much weight a magnet can lift. Online sources often claim that NdFeB magnets can lift objects weighing up to 600 times their own weight—but is this statement really accurate? Is there a calculation formula for magnet pull force? In this article, we take a closer look at what people commonly refer to as a magnet’s “pulling power.” In most magnet applications, magnetic flux or magnetic flux density is used to evaluate magnet performance—especially in motor

In our previous article, Effects of Heavy Rare Earth Elements (Dy, Tb, Gd, Ho) on Sintered NdFeB Magnet Properties, we discussed how heavy rare earth elements are used to enhance coercivity and high-temperature performance—often at the expense of cost and magnetic output. Building on that discussion, this article focuses on a different but equally important approach: substituting neodymium (Nd) and iron (Fe) with light rare earth elements and selected metallic additives. Elements such as La, Ce, and Pr, as well

As its name suggests, sintered NdFeB is an alloy material based on the compound Nd₂Fe₁₄B, which is formed from neodymium (Nd), iron (Fe), and boron (B). However, sintered NdFeB is not a single-phase material. Its microstructure consists of three main phases: the Nd₂Fe₁₄B phase, which is the primary and functional phase, a boron-rich phase (also known as the Nd₁.₁Fe₄B₄ phase), and a neodymium-rich phase, often referred to as the rare-earth-rich phase. Among these, the Nd₂Fe₁₄B phase dominates and serves as

Sintered NdFeB magnets are well known for being highly susceptible to oxidation and corrosion, which can eventually lead to a decline—or even a complete loss—of magnetic performance. For this reason, proper surface protection is essential before the magnets are put into use. In one of our previous articles, Preventing Corrosion: The Essential Guide to Neodymium Magnet Coating/Plating, we introduced the major surface-finishing options for sintered NdFeB magnets. In addition to electroplating, NdFeB magnets can also be treated using electroless plating,

Certification is essentially a form of quality and credibility assurance. According to the definitions provided by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC), certification refers to a conformity assessment activity in which an accredited certification body verifies that a company’s products, services, or management systems comply with relevant standards, technical specifications (TS), or mandatory requirements. The benefits of certification are clear: It serves as the “credit passport” of a product, a “health check report” of

In our earlier article on Mitigating Eddy Current Losses in Rare-earth Permanent Magnets, we explained why eddy currents occur and how they can lead to heat generation and demagnetization in high-speed motors. Building on that foundation, this article introduces one of the most effective engineering solutions for reducing eddy current loss—magnet segmentation. A magnet produced using segmentation technology is often referred to as a laminated magnet, segmented magnet, or sectioned magnet. The concept is straightforward: instead of using a single

How NdFeB Magnets Are Tested: Surface Field, Flux, Magnetic Moment, and Density Today, we will focus on the principles and methods used for relative magnetic property testing of sintered NdFeB magnets. NdFeB products come in many different shapes and sizes, and while most customers specify the magnetic grade, some also request comparative magnetic performance tests on samples. Typical customer requests may include: checking the surface magnetic field, measuring the magnetic flux, or verifying the magnetic moment of selected magnets. To

Origin of Magnetism in Permanent Magnets The magnetic properties of permanent magnets primarily come from their crystal structure, which allows them to become strongly magnetized. Even after the external magnetic field is removed, the magnet retains its magnetism. Therefore, the magnetization process (also called charging or polarization) is a critical step for permanent magnetic materials such as NdFeB (Neodymium-Iron-Boron) to obtain and exhibit strong magnetism. Isotropic vs. Anisotropic Magnets Magnetic materials can be classified into isotropic and anisotropic magnets: Type