Iron-silicon-aluminum-nickel soft magnetic powder core with effective magnetic permeability of 125 for boost inductor and preparation method thereof

[0041] Example 1

[0042] Select the original powder with a particle size of -200 mesh, and the mass percentages of the commercially available alloy composition are Si 4.0%, Al 3.5%, Ni 2.0%, and the remaining Fe, silicon, aluminum, nickel magnetic powder 1000.0g; then, add 0.3g of epoxy resin, 1.0g SiO 2 The powder, 10.0g of acetone and 90.0g of water were stirred at room temperature for 20 minutes to form a uniform mixed slurry; then, the mixed slurry was heated to 100°C and kept warm and stirred for 35 minutes. After the warming, it was dried The iron, silicon, aluminum and nickel insulating powder is sieved with a 100 mesh screen; to the sieved powder, 3.0 g of polyamide resin binder and 4.0 g of talc release agent are added, and mixed uniformly to obtain The magnetic powder; the uniformly mixed powder is pressed into a powder core blank with a pressing pressure of about 2300MPa. The powder core blank is an annular powder core with an outer diameter of 33.02mm × an inner diameter of 19.94mm × a height of 10.67mm; nitrogen is used as protection Air, heat the pressed powder core blank at 800°C for 120 minutes to obtain a semi-finished magnetic powder core; finally, spray a layer of insulating and high temperature resistant epoxy resin coating on the surface of the semi-finished magnetic powder to obtain a finished metal soft magnetic powder core.

[0043] A 32-turn inductance coil is wound on the iron-silicon-aluminium-nickel metal soft magnetic powder core with an enameled wire with a wire diameter of Φ1.12mm and a wire length of 0.9m. The measured magnetic and electrical properties of the powder core are as follows:

[0044] (1) Under the condition of 100kHz/1V, the inductance L=132.64μH;

[0045] (2) Under the condition of 100kHz/1V, the quality factor Q=75.73;

[0046] (3) DC superposition performance under 100kHz condition: when H=100Oe, L H /L 0 =34.69%; when H=200Oe, L H /L 0 = 15.29%;

[0047] (4) Under the condition of 50kHz/100mT, the volume loss of FeSiAlNi soft magnetic powder core: Pv=320.69mW/cm 3.

[0048] figure 1 It is a graph of the DC bias performance of the iron-silicon-aluminum-nickel soft magnetic powder core in Example 1 under the condition of 0Oe~200Oe. With the increase of the DC bias field strength, the DC bias performance of the powder core gradually decreases; under the condition of 100Oe, The DC bias performance of FeSiAlNi powder core reaches 34.69%, and the DC bias performance is excellent; figure 2 It is the graph of the effective permeability change of the sendust soft magnetic powder core under the condition of 20Hz~2MHz in Example 1. With the increase of the test frequency, the effective permeability of the sendust soft magnetic powder core has been maintained at around 125. Has excellent frequency stability characteristics.

[0049] Example 2

[0050] Select the original powder particle size of -200 mesh, the mass percentages of the commercially available alloy composition are Si 4.0%, Al 3.5%, Ni 2.0%, and the rest is 1000.0g of Fe-Si-Al-Ni magnetic powder; then, add 0.8g of epoxy resin, 0.5g SiO 2 The powder, 10.0g of acetone and 90.0g of water were stirred at room temperature for 20 minutes to form a uniform mixed slurry; then, the mixed slurry was heated to 140°C and kept warm and stirred for 15 minutes. After the warming, it was dried The iron-silicon-alumina-nickel insulating powder is sieved with a 100-mesh sieve; add 3.0g of phenolic resin binder and 4.0g of mica powder release agent to the sieved powder, and mix them evenly, using a compression pressure of about The uniformly mixed powder is compressed into powder core blanks for 2500 MPa. The powder core blanks are annular powder cores with an outer diameter of 33.02 mm × an inner diameter of 19.94 mm × a height of 10.67 mm; nitrogen is used as a protective gas to compress the powder into a shape. The core blank is kept at 850°C for 100 minutes to obtain a semi-finished magnetic powder core; finally, a layer of insulating and high temperature resistant epoxy resin coating is sprayed on the surface of the semi-finished magnetic powder to obtain a finished metal soft magnetic powder core.

[0051] A 32-turn inductance coil is wound on the iron-silicon-aluminium-nickel metal soft magnetic powder core with an enameled wire with a wire diameter of Φ1.12mm and a wire length of 0.9m. The measured magnetic and electrical properties of the powder core are as follows:

[0052] (1) Under the condition of 100kHz/1V, the inductance L=135.24μH;

[0053] (2) Under the condition of 100kHz/1V, the quality factor Q=70.55;

[0054] (3) DC superposition performance under 100kHz condition: when H=100Oe, L H /L 0 =34.54%; when H=200Oe, L H /L 0 = 15.33%;

[0055] (4) Under the condition of 50kHz/100mT, the volume loss of FeSiAlNi soft magnetic powder core: Pv=334.48mW/cm 3.

[0056] image 3 It is a graph showing the change of DC bias performance of Fe-Si-Al-Ni soft magnetic powder core under the condition of 0Oe~200Oe in Example 2. As the DC bias field strength increases, the DC bias performance of the powder core gradually decreases; under the condition of 100Oe, The DC bias performance of FeSiAlNi powder core reaches 34.54%, and the DC bias performance is excellent; Figure 4 It is a graph of the effective permeability of the iron-silicon-aluminium-nickel soft magnetic powder core under the condition of 20Hz~2MHz in Example 2; with the increase of the test frequency, the effective magnetic permeability of the iron-silicon-aluminium-nickel soft magnetic powder core has been maintained at around 125. Has excellent frequency stability characteristics.

[0057] Example 3

[0058] Select 1000.0g of iron-silica-aluminum-nickel magnetic powder with the original powder particle size of -200 mesh as Si 4%, Al 4.5%, Ni 1.5%, and the remaining Fe; then add 0.5g of epoxy resin , 0.7g of SiO 2 The powder, 10.0g of acetone and 90.0g of water were stirred at room temperature for 20 minutes to form a uniform mixed slurry; then, the mixed slurry was heated to 120°C and kept warm and stirred for 25 minutes. After the warming, it was dried The iron-silicon-aluminum-nickel insulating powder is sieved with a 100-mesh sieve; to the sieved powder, 3.0g of siloxane resin binder and 4.0g of zinc stearate release agent are added and mixed evenly, The magnetic powder to be formed is obtained; the uniformly mixed powder is pressed into a powder core blank with a pressing pressure of about 2800MPa, wherein the powder core blank is an annular powder core with an outer diameter of 33.02mm × an inner diameter of 19.94mm × a height of 10.67mm; nitrogen is used As a protective gas, heat the pressed powder core blank at 900°C for 100 minutes to obtain a semi-finished magnetic powder core; finally, spray a layer of insulating and high temperature resistant epoxy resin coating on the surface of the semi-finished magnetic powder to obtain a finished metal soft magnetic powder core .

[0059] A 32-turn inductance coil is wound on the iron-silicon-aluminium-nickel metal soft magnetic powder core with an enameled wire with a wire diameter of Φ1.12mm and a wire length of 0.9m. The measured magnetic and electrical properties of the powder core are as follows:

[0060] (1) Under the condition of 100kHz/1V, the inductance L=129.36μH;

[0061] (2) Under the condition of 100kHz/1V, the quality factor Q=85.77;

[0062] (3) DC superposition performance under 100kHz condition: when H=100Oe, L H /L 0 =34.90%; when H=200Oe, L H /L 0 = 15.50%;

[0063] (4) Under the condition of 50kHz/100mT, the volume loss of FeSiAlNi soft magnetic powder core: Pv=315.67mW/cm 3.

[0064] Figure 5 It is a graph showing the change of DC bias performance of Fe-Si-Al-Ni soft magnetic powder core under the condition of 0Oe~200Oe in Example 3. As the DC bias field strength increases, the DC bias performance of the powder core gradually decreases; under the condition of 100Oe, The DC bias performance of FeSiAlNi powder core reaches 34.90%, and the DC bias performance is excellent; Image 6 It is a graph of the effective permeability change of the sendust soft magnetic powder core under the condition of 20Hz~2MHz in Example 3. With the increase of the test frequency, the effective permeability of the sendust soft magnetic powder core has been maintained at around 125. Has excellent frequency stability characteristics.