Neodymium block magnets, also called rectangular or square magnets, are made from a sintered neodymium-iron-boron alloy. These magnets feature a flat and angular shape, offering a broad contact surface and strong holding power. Their structure makes them particularly effective in magnetic clamping, mounting, and structural applications. Block magnets are commonly used in motors, linear actuators, magnetic separators, and industrial automation systems.
NdFeB block magnets combine high magnetic strength with a practical geometric form. Their rectangular shape provides a larger surface area, which increases their holding force. They are highly resistant to demagnetization and perform well under standard operating temperatures.
Why choose Sintered Neodymium Block Magnet
● Large contact area: Block magnets provide strong adhesive force due to their broad surface, ideal for mounting and structural support.
● Highly customizable: Available in a variety of lengths, widths, and thicknesses to fit unique application requirements.
● Easy integration: Their flat surfaces make them simple to bond or insert into housings and assemblies.
● Durable and corrosion-resistant: Protective coatings such as nickel, zinc, or epoxy extend their lifespan.
● Reliable performance: Stable magnetic field output even in demanding environments.
NdFeB block magnets are widely used in industrial equipment, electric motors, magnetic couplings, magnetic chucks, and energy-efficient devices. As industries strive to reduce energy usage and carbon emissions, block magnets play an increasingly important role in driving innovation across sectors such as automation, transportation, and renewable energy.
| Material grade | Remanence Br (T/kG) | Coercivity Hcb (kOe/kA/m) | Intrinsic Coercivity Hcj (kOe/kA/m) | Maximum Energy Product (MGOe/kJ/m3) | Dy | Tb | Remarks |
| KN35 | ≥1.18(11.8) | ≥10.8(860) | ≥12(955) | 33～36(263～287) | √ | × | Scrap Inclusion |
| KN38 | ≥1.23(12.3) | ≥10.8(860) | ≥12(955) | 36～39(287～310) | √ | × | Scrap Inclusion |
| KN40 | ≥1.26(12.6) | ≥11.0(876) | ≥12(955) | 38～41(302～326) | √ | × | Scrap Inclusion |
| KN42 | ≥1.29(12.9) | ≥11.0(876) | ≥12(955) | 40～43(318～342) | √ | × | Scrap Inclusion |
| KN45 | ≥1.33(13.3) | ≥11.0(876) | ≥12(955) | 43～46(342～366) | × | × | |
| KN48 | ≥1.37(13.7) | ≥10.8(860) | ≥12(955) | 46～49(366～390) | × | × | |
| KN50 | ≥1.39(13.9) | ≥10.5(836) | ≥12(955) | 47～51(374～406) | × | × | |
| KN52 | ≥1.42(14.2) | ≥10.0(796) | ≥11(876) | 49～53(390～422) | × | × | |
| KN55 | ≥1.46(14.6) | ≥9.0(716) | ≥11(876) | 52～56(414～446) | × | × | |
| KN35M | ≥1.18(11.8) | ≥10.8(860) | ≥14(1114) | 33～36(263～287) | √ | × | Scrap Inclusion |
| KN38M | ≥1.23(12.3) | ≥11.0(876) | ≥14(1114) | 36～39(287～310) | √ | × | Scrap Inclusion |
| KN40M | ≥1.26(12.6) | ≥11.4(910) | ≥14(1114) | 38～41(302～326) | √ | × | Scrap Inclusion |
| KN42M | ≥1.29(12.9) | ≥11.8(939) | ≥14(1114) | 40～43(318～342) | √ | × | Scrap Inclusion |
| KN45M | ≥1.33(13.3) | ≥11.8(939) | ≥14(1114) | 43～46(342～366) | √ | × | Scrap Inclusion |
| KN48M | ≥1.37(13.7) | ≥11.8(939) | ≥14(1114) | 46～49(366～390) | × | × | |
| KN50M | ≥1.39(13.9) | ≥11.5(915) | ≥14(1114) | 47～51(374～406) | × | × | |
| KN52M | ≥1.42(14.2) | ≥10.8(860) | ≥13(1035) | 49～53(390～422) | × | × | |
| KN54M | ≥1.46(14.6) | ≥10.8(860) | ≥13(1035) | 52～56(414～446) | × | × | |
| KN35H | ≥1.18(11.8) | ≥10.8(860) | ≥17(1353) | 33～36(263～287) | √ | × | |
| KN38H | ≥1.23(12.3) | ≥11.0(876) | ≥17(1353) | 36～39(287～310) | √ | × | |
| KN40H | ≥1.26(12.6) | ≥11.4(910) | ≥17(1353) | 38～41(302～326) | √ | × | |
| KN42H | ≥1.29(12.9) | ≥11.8(939) | ≥17(1353) | 40～43(318～342) | √ | × | |
| KN45H | ≥1.33(13.3) | ≥11.8(939) | ≥17(1353) | 43～46(342～366) | √ | × | |
| KN48H | ≥1.37(13.7) | ≥11.8(939) | ≥17(1353) | 46～49(366～390) | √ | × | |
| KN50H | ≥1.39(13.9) | ≥11.5(915) | ≥16(1274) | 47～51(374～406) | √ | × | |
| KN52H | ≥1.42(14.2) | ≥10.8(860) | ≥16(1274) | 49～53(390～422) | √ | × | |
| KN54H | ≥1.46(14.6) | ≥10.8(860) | ≥16(1274) | 52～56(414～446) | √ | √ | |
| KN30SH | ≥1.08(10.8) | ≥10.0(796) | ≥20(1592) | 28～31(223～247) | × | × | |
| KN33SH | ≥1.14(11.4) | ≥10.5(836) | ≥20(1592) | 31～34(247～271) | × | × | |
| KN35SH | ≥1.18(11.8) | ≥10.8(860) | ≥20(1592) | 33～36(263～287) | √ | × | |
| KN38SH | ≥1.23(12.3) | ≥11.0(876) | ≥20(1592) | 36～39(287～310) | √ | × | |
| KN40SH | ≥1.26(12.6) | ≥11.4(910) | ≥20(1592) | 38～41(302～326) | √ | × | |
| KN42SH | ≥1.29(12.9) | ≥11.8(939) | ≥20(1592) | 40～43(318～342) | √ | × | |
| KN45SH | ≥1.33(13.3) | ≥11.8(939) | ≥20(1592) | 43～46(342～366) | √ | × | |
| KN48SH | ≥1.37(13.7) | ≥11.8(939) | ≥19(1512) | 46～49(366～390) | √ | × | |
| KN50SH | ≥1.39(13.9) | ≥11.5(915) | ≥19(1512) | 47～51(374～406) | × | √ | |
| KN52SH | ≥1.42(14.2) | ≥10.8(860) | ≥19(1512) | 49～53(390～422) | × | √ | |
| KN54SH | ≥1.46(14.6) | ≥10.8(860) | ≥19(1512) | 52～56(414～446) | × | √ | |
| KN30UH | ≥1.08(10.8) | ≥10.0(796) | ≥25(1990) | 28～31(223～247) | √ | × | |
| KN33UH | ≥1.14(11.4) | ≥10.5(836) | ≥25(1990) | 31～34(247～271) | √ | × | |
| KN35UH | ≥1.18(11.8) | ≥10.8(860) | ≥25(1990) | 33～36(263～287) | √ | × | |
| KN38UH | ≥1.23(12.3) | ≥11.0(876) | ≥25(1990) | 36～39(287～310) | √ | × | |
| KN40UH | ≥1.26(12.6) | ≥11.4(910) | ≥25(1990) | 38～41(302～326) | √ | × | |
| KN42UH | ≥1.29(12.9) | ≥11.8(939) | ≥25(1990) | 40～43(318～342) | √ | × | |
| KN45UH | ≥1.33(13.3) | ≥11.8(939) | ≥24(1910) | 43～46(342～366) | √ | √ | |
| KN48UH | ≥1.37(13.7) | ≥11.8(939) | ≥24(1910) | 46～49(366～390) | √ | √ | |
| KN50UH | ≥1.39(13.9) | ≥11.5(915) | ≥24(1910) | 47～51(374～406) | √ | √ | |
| KN52UH | ≥1.42(14.2) | ≥10.8(860) | ≥24(1910) | 49～53(390～422) | √ | √ | |
| KN30EH | ≥1.08(10.8) | ≥10.0(796) | ≥30(2388) | 28～31(223～247) | √ | √ | |
| KN33EH | ≥1.13(11.3) | ≥10.5(836) | ≥30(2388) | 31～34(247～271) | √ | √ | |
| KN35EH | ≥1.17(11.7) | ≥10.8(860) | ≥30(2388) | 33～36(263～287) | √ | √ | |
| KN38EH | ≥1.22(12.2) | ≥11.0(876) | ≥30(2388) | 36～39(287～310) | √ | √ | |
| KN40EH | ≥1.25(12.5) | ≥11.0(876) | ≥29(2308) | 38～41(302～326) | √ | √ | |
| KN42EH | ≥1.28(12.8) | ≥10.0(796) | ≥29(2308) | 40～43(318～342) | √ | √ | |
| KN45EH | ≥1.33(13.3) | ≥11.8(939) | ≥29(2308) | 43～46(342～366) | √ | √ | |
| KN48EH | ≥1.37(13.7) | ≥11.8(939) | ≥29(2308) | 46～49(366～390) | √ | √ | |
| KN30TH | ≥1.08(10.8) | ≥10.0(796) | ≥35(2786) | 28～31(223～247) | √ | √ | |
| KN33TH | ≥1.13(11.3) | ≥10.5(836) | ≥35(2786) | 31～34(247～271) | √ | √ | |
| KN35TH | ≥1.17(11.7) | ≥10.8(860) | ≥35(2786) | 33～36(263～287) | √ | √ | |
| KN38TH | ≥1.22(12.2) | ≥11.0(876) | ≥34(2706) | 35～39(279～310) | √ | √ | |
| KN40TH | ≥1.25(12.5) | ≥10.5(836) | ≥34(2706) | 38～41(302～326) | √ | √ | |
| KN42TH | ≥1.28(12.8) | ≥10.0(796) | ≥34(2706) | 40～43(318～342) | √ | √ |
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Sintered NdFeB Permanent Magnetic Materials
Zhejiang Kaiven Magnet Co., Ltd is leading Neodymium Ring Magnet manufacturers and suppliers in China, The company's current production process of sintered NdFeB permanent magnet materials can be divided into two parts: the blank process (also known as the "front process" in the industry) and the finished product process (also known as the "post process" in the industry): the blank process is the praseodymium Neodymium metal, pure iron, ferroboron and other raw materials are used to make NdFeB blanks; the finished product process is to process NdFeB blanks by mechanical processing and surface treatment to obtain NdFeB magnets. We also OEM/ODM custom sintered NdFeB ring magnet. The specific production process flow chart is as follows:
Kaiven is committed to becoming a world-renowned supplier of permanent magnet material application solutions in the field of new generation consumer electronics and energy-saving home appliances. Welcome to visit our NdFeB ring magnet factory in China.
The company applies technologies such as casting columnar crystal growth control technology, grain refinement and micro-optimization technology, etc., and is committed to improving the consistency of powder and giving full play to the performance potential of rare earth. By improving the smelting microstructure, applying fine-grain technology, and optimizing the mixing process, etc., significantly improving the performance of NdFeB magnets.
The company has applied and improved low-oxygen magnet preparation technology and cold isostatic pressing technology, so that NdFeB magnets are in a low-oxygen state during the pressing process, and the preparation of molding blanks is continuously optimized, which effectively reduces the loss of rare earth. The application of low-temperature sintering heat treatment technology has further improved the sintering process. Adjusting the temperature to a suitable state can give full play to the performance of the formula. The representative products are high-performance N55 magnets prepared by low-oxygen technology and N38UH magnets produced by near-net molding technology.
In order to pursue the accurate precision of customer customization, the company applies high-performance ultra-thin small special-shaped permanent magnet preparation technology to carry out high-efficiency and low-loss precision machining of NdFeB blanks, breaking through the technical bottleneck of high-performance thin and small magnet processing difficulty, and Strictly control product appearance defects through intelligent image appearance automatic inspection technology to improve inspection efficiency and accuracy.
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Established in 1987. With advanced technology and strong R&D capabilities, Kaiven Magnet has grown into a leading ferrite magnets and neodymium magnets manufacturer and exporter in China.
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