Understanding Neodymium Magnets
These custom Industrial strength ultra-powerful compact superior thermal stability high heat resistant round shape with 4mm hole nickel coated neodymium magnet (D10 × 6 × (4 mm hole) is designed to deliver exceptional magnetic performance in a durable and compact form. Manufactured from high-grade Neodymium (NdFeB), the strongest permanent magnet material available, it provides outstanding holding strength even in space-constrained environments. Its nickel coating ensures excellent corrosion resistance, a sleek professional finish, and enhanced wear protection, making it suitable for long-term use in both indoor and outdoor settings. Engineered for superior thermal stability, this magnet maintains reliable performance even under high-temperature conditions. With its round shape and center hole, it integrates seamlessly into industrial assemblies, construction projects, and precision applications. Commonly used for secure metal positioning in construction, fastening and alignment in manufacturing, reliable operation in medical imaging systems, and sensitive electronic equipment, this magnet also excels in DIY projects and everyday organizational tasks. Compact yet ultra-powerful, it offers dependable, long-lasting magnetic performance across a wide range of industries.
D10mm × 6mm × (4 mm hole) Round Neodymium – Nickel Coated, Magnet
N42 Custom industrial strength ultra-powerful heavy duty compact superior thermal stability high heat resistant round shape with 4mm hole nickel coated neodymium magnets are easy to install and provide a strong magnetic hold, making them suitable for a wide range of applications. In industrial environments, they’re often used to secure safety covers, fix metal plates in place, or hold components steady during use. Around the house, they work well for magnetic latches, organizing garage tools, or keeping heavy doors closed. In retail, they’re commonly used to mount signs and displays where strength and flexibility are important. Their durable design and wide range of uses make them a practical solution for many everyday tasks.
Magnet Grade: N42
These high-grade custom industrial strength ultra-powerful heavy duty compact superior thermal stability high heat resistant round shape with 4mm hole nickel coated neodymium magnets offer a balanced combination of strength and versatility, with a maximum energy product of around 42 MGOe. Well-suited for various applications, including motors, sensors, and precision assemblies, they deliver consistent magnetic performance. Their reliable field strength makes them a preferred choice for consumer electronics and technical equipment alike. Widely adopted across industries, N42 magnets are valued for their dependable and efficient performance.
Protective Coating: Ni-Cu-Ni
These Ni-Cu-Ni plated neodymium magnets feature a robust triple-layer coating that shields the neodymium core from moisture and oxygen, preventing corrosion over time. The polished, glossy finish adds aesthetic appeal while ensuring reliable performance in environments with mild moisture exposure. For harsher applications where greater durability is required, epoxy coatings may be more suitable for long-term protection.
APPLICATION EXAMPLES
Material Neodymium (NdFeB)
Product Name: D10mm × 6mm × (4 mm hole) Industrial strength precision-engineered ultra-powerful compact cylinder-shaped nickel-coated neodymium magnet
Magnetic Grade: N42 (Br ≥ 13.5 kGs, Hcj ≥ 12 kOe)
Thickness: D10 × 6 × (4 mm hole)
Countersunk Hole: 5.5mm
Dimensional Tolerance: Length ±0.05mm, Width ±0.05mm, Thickness ±0.05mm
Magnetisation Direction: Axially Magnetised
Polarity: Countersunk Face North
Operating Temperature: ≤80°C (high-temp version available)
Density: ≥7.5 g/cm³
Surface Magnetic Field: 3800 ±200 Gauss (measured with TM-801 Gauss meter)
Magnetic Flux: 2.3 mWb (measured with fluxmeter)
The manufacturing process of this Precision customized strong magnetic force high energy density compact bore magnetic pot ndfeb magnet are as following:
Professional pulse magnetization equipment is used to inject strong and stable magnetic fields, ensuring the magnet meets design specifications and performs reliably under high load or high-frequency operation.

Visual Inspection: Under standardized lighting, trained QC staff check for cracks, chipping, inclusions, pores, or oxidation

Image Measurement System: High-res cameras and algorithms conduct non-contact 2D measurements, especially for complex or irregular shapes, ensuring efficiency and objectivity in mass production.
Automated Intelligent Inspection: High-speed cameras with AI algorithms detect and reject defects (e.g., cracks, scratches, discoloration) and dimensional anomalies, improving yield and reducing human error.

To ensure magnet maintain excellent corrosion resistance in complex or harsh environments, the salt spray test is an essential accelerated aging method. It simulates long-term exposure to marine climates, industrial pollution, humidity, or acidic and alkaline conditions, allowing for a reliable evaluation of the protective performance and durability of the magnet's surface coating.

Constant Temperature & Humidity Test: Performed under 85°C and 85% RH for 96–500 hours. Performance and appearance are compared before and after testing.

Defect Elimination: 100% inspection using calipers, projectors, visual checks, and automated systems to reject cracked, chipped, oxidized, or coated-defective magnets.
Uniform Magnetization & Structured Arrangement: Magnets are uniformly magnetized and arranged for optimal packaging based on customer requirements to ensure performance and facilitate automated assembly.
Vacuum Sealed Packaging: Multi-layer vacuum sealing with moisture barriers, desiccants or nitrogen, prevents corrosion and magnetic interference during storage and shipping.
Customized Outer Packaging: Shock-proof, moisture-resistant, and anti-magnetic leakage packaging (e.g., multilayer cartons, plastic boxes, metal shielding) ensures compliance with international logistics standards. Each box includes a product list, labels, and tracking codes.

We know logistics is more than moving goods — it’s about delivering your promise. Our trusted solutions offer:
Global shipping coverage
Real-time tracking from origin to destination
Enhanced safety at every stage
Dedicated service with customized shipping plans
With our robust land, sea, and air network, your business moves faster, safer, and with complete confidence.

Dongguan Jinconn New Material Holdings Co., Ltd. is a publicly listed enterprise offering integrated R&D, manufacturing, and sales of rare earth magnets. Based in Xiaohe Industrial Zone, Daojiao Town, Dongguan, we serve clients across China and globally.
20+ years of magnet manufacturing expertise
Strict quality control & customization capability
Multilingual technical support with global delivery
RoHS and REACH compliant

Please contact us for free samples, magnet customization solutions, and MSDSRoHS, ISO 9001, QC080000, IATF 16949, ISO 14001, ISO 27001 or other relevant certificates!
Handle with care: Neodymium magnets are brittle and can chip or crack if dropped or impacted.
Avoid injury: Always slide magnets apart—do not force or pry them to separate.
Check polarity before use: Incorrect installation may cause malfunction or damage to equipment.
Store properly: Keep in a dry, neutral environment; avoid contact with moisture, acids, or corrosive substances.
Keep away from sensitive electronics: Do not place near hard drives, magnetic cards, pacemakers, or similar devices.

Customizable magnet dimensions, geometry, and surface coatings (including layer count, thickness, and color)
Precision magnetization orientation and adjustable magnetic field intensity
Optional laser marking for logos, part numbers, or traceability codes
Specialized packaging and pull-force testing tailored to your application needs
With deep expertise in magnetic materials, we deliver solutions for industries like EVs, smart manufacturing, and electronics. Our strong technical capabilities and product consistency have earned the trust of customers worldwide.
Contact Us:
Phone/WhatsApp/WeChat: +86 13829120676
Email: Info@jinconn.com
Address: Xiaohe Industrial Zone, Daojiao Town, Dongguan City, Guangdong Province, China




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