SM 32x325 [2xM8] / N52 - magnetic separator

Strengths as well as weaknesses of NdFeB magnets.

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

• They do not lose strength, even after nearly 10 years – the decrease in strength is only ~1% (based on measurements),
• They do not lose their magnetic properties even under strong external field,
• By applying a decorative coating of nickel, the element gains an professional look,
• Neodymium magnets deliver maximum magnetic induction on a small surface, which ensures high operational effectiveness,
• Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
• Due to the possibility of flexible forming and customization to unique requirements, magnetic components can be created in a variety of geometric configurations, which increases their versatility,
• Wide application in advanced technology sectors – they are used in computer drives, electromotive mechanisms, precision medical tools, and multitasking production systems.
• Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages of neodymium magnets:

• At very strong impacts they can crack, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
• When exposed to high temperature, neodymium magnets experience a drop in force. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
• Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material immune to moisture, in case of application outdoors
• We recommend cover - magnetic holder, due to difficulties in creating nuts inside the magnet and complex shapes.
• Possible danger related to microscopic parts of magnets can be dangerous, if swallowed, which becomes key in the context of child health protection. Additionally, tiny parts of these products can disrupt the diagnostic process medical after entering the body.
• Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Maximum lifting capacity of the magnet – what affects it?

Holding force of 0 kg is a result of laboratory testing conducted under standard conditions:

• on a base made of mild steel, optimally conducting the magnetic flux
• whose transverse dimension reaches at least 10 mm
• with an ideally smooth contact surface
• without the slightest air gap between the magnet and steel
• for force acting at a right angle (in the magnet axis)
• at room temperature

What influences lifting capacity in practice

Holding efficiency impacted by working environment parameters, mainly (from priority):

• Air gap (betwixt the magnet and the plate), as even a microscopic distance (e.g. 0.5 mm) results in a drastic drop in lifting capacity by up to 50% (this also applies to varnish, corrosion or debris).
• Force direction – note that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops drastically, often to levels of 20-30% of the maximum value.
• Metal thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of converting into lifting capacity.
• Material composition – not every steel attracts identically. High carbon content worsen the interaction with the magnet.
• Smoothness – full contact is possible only on polished steel. Any scratches and bumps reduce the real contact area, reducing force.
• Temperature influence – hot environment reduces pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

* Lifting capacity was determined by applying a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular detachment force, whereas under shearing force the holding force is lower. Additionally, even a minimal clearance {between} the magnet’s surface and the plate decreases the holding force.