Ferrite Characteristics Materials

Ferroxcube Soft Ferrites Ferrite materials survey Ferroxcube Soft Ferrites Ferrite materials survey Properties specified in this section are related to room temperature (25 °C) unless otherwise stated. They have been measured on sintered, non ground ring cores of dimensions ∅25 × ∅15 × 10 mm which are not subjected to external stresses. Products generally comply with the material specification. However, deviations may occur due to shape, size and grinding operations etc. Specified product properties are given in the data sheets or product drawings. Ferrite material survey MAIN APPLICATION AREA Telecom filters Proximity sensors FREQUENCY RANGE (MHZ) < 0.1 Power transformers Power inductors General purpose transformers and inductors Wideband EMI-suppression Wideband transformers Balun transformers Bsat (mT) at 25 °C (1200 A/m ) TC (°C) ρ (Ωm) FERRITE TYPE AVAILABLE CORE SHAPES 3B46 3800 ≈ 545 ≥ 255 ≈ 10 MnZn 3B7 2300 ≈ 440 ≥ 170 ≈1 MnZn RM, P, PT, PTS, EP, E, Planar ER, RM/I, RM/ILP, PH MnZn 0.2 − 2 3D3 750 ≈ 380 ≥ 200 ≈2 < 0.2 3H3 2000 ≈ 360 ≥ 160 ≈2 MnZn 3E27 6000 ≈ 430 ≥ 150 ≈ 0.5 MnZn 3E28 4000 ≈ 440 ≥ 145 ≈1 MnZn MnZn Wideband signal transformers Pulse transformers Delay lines Line output transformers (LOT) µi at 25 °C MATERIAL 3E5 10000 ≈ 380 ≥ 125 ≈ 0.5 3E55 10000 ≈ 370 ≥ 100 ≈ 0.1 MnZn 3E6 12000 ≈ 390 ≥ 130 ≈ 0.1 MnZn 3E7 15000 ≈ 390 ≥ 130 ≈ 0.1 MnZn 3E8 18000 ≈ 380 ≥ 100 ≈ 0.1 MnZn 3E9 20000 ≈ 380 ≥ 100 ≈ 0.1 MnZn < 0.2 3C30 2100 ≈ 500 ≥ 240 ≈2 MnZn < 0.3 3C34 2100 ≈ 500 ≥ 240 ≈5 MnZn < 0.2 < 0.2 3C81 3C90 2700 2300 ≈ 450 ≈ 470 ≥ 210 ≥ 220 ≈1 ≈5 MnZn MnZn < 0.3 3C91 3000 ≈ 470 ≥ 220 ≈5 MnZn < 0.2 3C92 1500 ≈ 520 ≥ 280 ≈5 MnZn < 0.3 3C93 1800 ≈ 500 ≥ 240 ≈5 MnZn < 0.3 3C94 2300 ≈ 470 ≥ 220 ≈5 MnZn < 0.3 < 0.4 3C95 3C96 3000 2000 ≈ 530 ≈ 500 ≥ 215 ≥ 240 ≈5 ≈5 MnZn MnZn 0.2 − 0.5 3F3 2000 ≈ 440 ≥ 200 ≈2 MnZn 0.5 − 1 3F35 1400 ≈ 500 ≥ 240 ≈ 10 MnZn 1−2 3F4 900 ≈ 410 ≥ 220 ≈ 10 MnZn 1−2 3F45 900 ≈ 420 ≥ 300 ≈ 10 MnZn 2−4 3F5 650 ≈ 380 ≥ 300 ≈ 10 MnZn 4 − 10 4F1 80 ≈ 320(1) ≥ 260 ≈ 105 NiZn 10 − 100 3B1 900 ≈ 380 ≥ 150 ≈ 0.2 MnZn 1 − 30 3S1 4000 ≈ 400 ≥ 125 ≈1 MnZn 30 − 1000 3S3 350 ≈ 320 ≥ 225 ≈ 104 MnZn 10 − 300 3S4 1700 ≈ 320 ≥ 110 ≈ 103 MnZn 1 − 30 3S5 3800 ≈ 545 ≥ 255 ≈ 10 MnZn 30 − 1000 10 − 300 4A11 4A15 850 1200 ≈ 340 ≈ 350 ≥ 125 ≥ 125 ≈ 105 NiZn ≈ 105 NiZn 105 NiZn NiZn 10 − 300 4A20 2000 ≈ 260 ≥ 100 ≈ 30 − 1000 4B1 250 ≈ 360(1) ≥ 250 ≈ 105 125 380(1) ≥ 350 ≈ 10 5 NiZn ≈ 105 NiZn ≈ 105 NiZn 50 − 1000 30 − 1000 30 − 1000 4C65 4S2 4S3 850 250 ≈ ≈ 340 ≈ 360(1) ≥ 125 ≥ 250 RM, P, PT, PTS, EP, EP/LP, EPX, E, Planar ER, RM/I, RM/ILP, Toroids Toroids UR E, EI, Planar E, EC, EFD, EP, ETD, ER, Planar ER, U, RM/I, RM/ILP, P, P/I, PT, PTS, PM, PQ, Toroids (gapped), Bobbin cores BD, BDW, BDS, MLS, CMS, Cable shields, Rods, Toroids, WBS, WBC Ferroxcube Soft Ferrites MAIN APPLICATION AREA Ferrite materials survey FREQUENCY RANGE (MHZ) EMI-filters Current compensated chokes HF Tuning Bsat (mT) at 25 °C (1200 A/m ) TC (°C) ρ (Ωm) FERRITE TYPE 3C11 4300 ≈ 390 ≥ 125 ≈1 MnZn 3E25 6000 ≈ 390 ≥ 125 ≈ 0.5 MnZn 3E26 7000 ≈ 430 ≥ 155 ≈ 0.5 MnZn 3E5 10000 ≈ 380 ≥ 125 ≈ 0.5 MnZn 3E6 4A11 12000 850 ≈ 390 ≈ 340 ≥ 130 ≥ 125 ≈ 0.1 ≈ 105 MnZn NiZn AVAILABLE CORE SHAPES Toroids E, EI, U <1 3B1 900 ≈ 380 ≥ 150 ≈ 0.2 MnZn <2 <5 3D3 4B1 750 250 ≈ 380 ≈ 360(1) ≥ 200 ≥ 250 ≈2 ≈ 10 5 MnZn NiZn <5 4B2 250 ≈ 360(1) ≥ 335 ≈ 10 5 NiZn < 20 4C65 125 ≈ 380 (1) ≥ 350 ≈ 105 NiZn 250(2) ≥ 400 ≈ 105 NiZn ≥ 500 ≈ 105 NiZn 10 3 MnZn Toroids < 50 4D2 60 ≈ < 200 4E1 15 ≈ 220 (3) magnetic regulators < 0.2 3R1 absorber tiles < 1000 4S60 scientific particle accelerators µi at 25 °C MATERIAL 800 ≈ 410 ≥ 230 ≈ 2000 ≈ 260 ≥ 100 ≈ 105 NiZn Tiles 420(1) ≥ 250 ≈ 10 5 NiZn ≥ 400 ≈ 105 NiZn 105 NiZn Large toroids Machined ferrite products < 10 4B3 300 < 100 4E2 25 ≈ 350 (2) 310(1) < 10 4M2 140 <1 8C11 1200 < 10 8C12 900 ≈ ≈ Rods, Tubes, Wideband chokes ≈ 310 ≈ 260 ≥ 200 ≈ ≥ 125 ≈ 10 5 NiZn ≥ 125 105 NiZn ≈ 1. At 3000 A/m 2. At 10 kA/m 3. At 20 kA/m Iron powder material grade survey IRON POWDER MATERIAL µi at 25 °C Bsat (mT) at 25 °C (3000 A/m) MAXIMUM OPERATING TEMPERATURE (°C) 2P40 40 950 140 2P50 50 1000 140 2P65 65 1150 140 2P80 80 1400 140 2P90 90 1600 140 MAIN APPLICATION AREA EMI-suppression Output inductors AVAILABLE CORE SHAPES Toroids Typical mechanical and thermal properties PROPERTY Young’s modules MnZn FERRITE (90 to 150) × 103 NiZn FERRITE (80 to 150) × 10 3 UNIT N/mm2 Ultimate compressive strength 200 to 600 200 to 700 N/mm 2 Ultimate tensile strength 20 to 65 30 to 60 N/mm2 Vickers hardness 600 to 700 800 to 900 N/mm 2 Linear expansion coefficient (10 to 12) × 10−6 (7 to 8) × 10−6 K−1 Specific heat 700 to 800 750 Jkg−1 × K−1 Heat conductivity (3.5 to 5.0) × 10−3 (3.5 to 5.0) × 10−3 Jmm −1s−1 × K−1 Ferroxcube Soft Ferrites Ferrite materials survey RESISTIVITY Table 4 Ferrite is a semiconductor with a DC resistivity in the crystallites of the order of 10-3 Ωm for a MnZn type ferrite, and about 30 Ωm for a NiZn ferrite. FREQUENCY (MHz) Since there is an isolating layer between the crystals, the bulk resistivity is much higher: 0.1 to 10 Ωm for MnZn ferrites and 104 to 106 Ωm for NiZn and MgZn ferrites. This resistivity depends on temperature and measuring frequency, which is clearly demonstrated in Tables 1 and 2 which show resistivity as a function of temperature for different materials. Table 1 Resistivity as a function of temperature of a MnZn-ferrite (3C94) TEMPERATURE (°C) −20 RESISTIVITY (Ωm) ≈10 0 ≈7 20 ≈4 50 ≈2 100 ≈1 0.1 1 0 ≈104 ≈103 PERMITTIVITY The basic permittivity of all ferrites is of the order of 10. This is valid for MnZn and NiZn materials. The isolating material on the grain boundaries also has a permittivity of approximately 10. However, if the bulk permittivity of a ferrite is measured, very different values of apparent permittivity result. This is caused by the conductivity inside the crystallites. The complicated network of more or less leaky capacitors also shows a strong frequency dependence. Tables 5 and 6 show the relationship between permittivity and frequency for both MnZn and NiZn ferrites. RESISTIVITY (Ωm) 20 60 100 6 ≈10 ≈105 Resistivity as function of frequency for MnZn ferrites FREQUENCY (MHz) RESISTIVITY (Ωm) 0.1 ≈2 1 ≈0.5 10 100 ≈0.1 ≈0.01 PERMITTIVITY (εr) 0.1 ≈2.105 1 ≈105 10 100 Table 6 At higher frequencies the crystal boundaries are more or less short-circuited by heir capacitance and the measured resistivity decreases, as shown in Tables 3 and 4. Permittivity as a function of frequency for MnZn ferrites FREQUENCY (MHz) ≈5.107 ≈107 Table 3 ≈105 ≈5.104 10 Resistivity as a function of temperature of a NiZn-ferrite (4C65) TEMPERATURE (°C) RESISTIVITY (Ωm) 100 Table 5 Table 2 Resistivity as function of frequency for NiZn ferrites ≈5.104 ≈104 Permittivity as a function of frequency for NiZn ferrites FREQUENCY (MHz) PERMITTIVITY (εr) 0.001 0.01 ≈100 ≈50 1 ≈25 10 ≈15 100 ≈12