Preparation of bonded magnets (1) Magnetic powder and binder In the previous issue, we have learned about isotropic and anisotropic magnetic powders. In this issue, we will talk about the magnetic powders and adhesives of bonded magnets with different processes. The rare earth permanent magnet alloy used for bonded magnets is a submicron grain alloy [...]
Preparation of bonded magnets (1) Process classification Bonded magnets are composites composed of magnetic powders, binders, and appropriate additives. The magnetic properties of bonded magnets are mainly determined by the average performance of each magnetic powder with negligible interactions. Melting point metals or alloys are used as adhesives, but the adhesives used to form mass-produced [...]
Properties of hot-pressed and hot-deformed NdFeB magnets Hot-pressed and hot-deformed NdFeB magnets were successfully researched and developed almost simultaneously with sintered NdFeB magnets. In 1985, the General Motors Corporation (GM) Research Center of the United States reported that using hot pressing technology to press the quenched NdFeB magnetic powder in an argon environment at 700 [...]
Preparation process of sintered NdFeB magnets (1) - Raw material Today we start with the link of raw material preparation and alloy preparation. Sintered magnets usually use pure metals or intermediate alloys as raw materials, use the electromagnetic induction heating principle of eddy current generated by alternating magnetic fields in the raw materials, and conduct [...]
Preparation process of sintered NdFeB magnets (2) - Milling powder In the previous issue, we learned about alloy smelting and casting. After casting, the alloy needs to be made into powder through a pulverizing process before entering the subsequent processing process. Obtaining suitable powder shape, average particle size and particle size distribution is the basic [...]
Preparation process of sintered NdFeB magnets (3) - orientation forming Magnetic field orientation forming is to use the interaction between magnetic powder and external magnetic field to arrange the easy magnetization direction of powder particles so that it is consistent with the final magnetization direction of the magnet. This is the most commonly used method [...]
Preparation process of sintered NdFeB magnets (4) - Sintering, heat treatment and machining Sintering and heat treatment The blanks pressed by magnetic field orientation are sintered in a high vacuum or pure inert atmosphere to reach a high density close to 95% of the theoretical density. The magnet holes are in a closed structure, which [...]
NdFeB chemical composition analysis (ICP analysis) The chemical composition analysis of NdFeB materials generally includes: 1-Chemical composition analysis of raw materials, including the chemical composition of rare earth metal raw materials, as well as industrial pure Fe, B-Fe alloys and other metals, such as Ga, Al, Nb, Zr, etc.; 2- The chemical composition of the [...]
Pentagon suspends F-35 fighter jets because a magnet in the turbine is made in China More recently, America's F-35 fighter jet has made headlines again. The well-known British media "Reuters" published a message, citing the US military Pentagon as saying that the lubricating oil pump of the US Honeywell engine contains samarium cobalt alloy produced [...]
The First Global Rare Earth Industry Association Was Established A few days ago, the Global Rare Earth Industry Association (REIA) was established at the headquarters of the EIT Raw Materials Organization in Brussels, Belgium. The Global Rare Earth Industry Association (REIA) is an international rare earth association headquartered in Brussels, providing an interoperability platform for [...]
Are Magnets Really Threatening Electronics? Many people are paranoid about having magnets close to electronic products, worrying that the screen will be deformed, that the stored files will disappear, and that the smartphone will be damaged by the magnet. Are people's worries unfounded? Or do magnets really pose a dire threat to electronics? The effect [...]
