CN103342562A - Sintering process of magnesium-iron ferrite small magnetic core - Google Patents

Abstract

The invention discloses a sintering process of a magnesium-iron ferrite small magnetic core. The sintering process comprises the following steps of: (1), paving a layer of powder which is the same in material as that of blank pieces of the magnesium-iron ferrite small magnetic core on a setter plate, stacking the blank pieces of the magnesium-iron ferrite small magnetic core, and burying the blank pieces of the magnesium-iron ferrite small magnetic core by using the powder which is the same in material as that of the blank pieces; (2), sintering the blank pieces of the magnesium-iron ferrite small magnetic core, which are processed in the step (1), in a kiln and sintering; and (3), placing the sintered product in a vibrating-grinding machine for vibrating and grinding, ultrasonically cleaning, and placing for more than 24 hours to obtain the magnesium-iron ferrite small magnetic core. The sintering process of the magnesium-iron ferrite small magnetic core disclosed by the invention is suitable for sintering the magnesium-iron ferrite small magnetic core with the dimension smaller than 10mm, capable of effectively preventing the small magnetic core from being deformed and twisted in a high-temperature sintering process and capable of effectively preventing zinc replacement with the setter plate, so that the rate of finished products is 95% or higher.

Description

The little magnetic core sintering process of a kind of Mn-Zn ferrite

Technical field

The invention belongs to the supplement production technology that manganese-zinc ferrite core is made, relate to the little magnetic core sintering process of a kind of Mn-Zn ferrite specifically.

Background technology

Integrated along with electronic product, miniaturization, transformer is done littler and littler, and corresponding magnetic core product is also done littler and littler.In the miscellaneous goods production process, because the powder consumption is few, the unit price height, the profit height, its prime cost is on manual sorting man-hour.Generally speaking, more bigger product can pass through automatic blank arranging machine, finishing rolls operation automatically; And some especially little products as the product of length dimension less than 5mm, can't adopt the automatic blank arranging machine operation.Reason has two: 1, magnetic core is too little, and the automatic blank arranging machine precision is not enough; 2, little blank, more open because density is low, the fragile blank of automatic blank arranging machine mechanical work.And design is specifically designed to High Precision Automatic row's base machine of miscellaneous goods, and cost is too high.

The routine operation mode usually adopts burnt in a heap, but miscellaneous goods is too small, the yielding distortion of magnetic core during high temperature burnt in a heap, and simultaneously and hold and burn anti-material and contact, miscellaneous goods is held the anti-material component of burning to be influenced greatly, holds the anti-material of burning and is generally AL ₂O ₃, can produce replacement(metathesis)reaction with zinc in the Mn-Zn ferrite, the therefore product that contacts with anti-material, electrical property sharply worsens.

Summary of the invention

When the objective of the invention is to solve the existing little magnetic core of Mn-Zn ferrite and adopting sintering burnt in a heap the yielding distortion of magnetic core and with the problem of load bearing board generation zinc displacement, provide a kind of Mn-Zn ferrite little magnetic core sintering process.

The present invention realizes that the technical scheme that above-mentioned purpose adopts is as follows;

The little magnetic core sintering process of a kind of Mn-Zn ferrite comprises the steps,

1) on load bearing board, spreads one deck powder identical with the blank material of the little magnetic core of Mn-Zn ferrite earlier, stack the little magnetic core blank of Mn-Zn ferrite then, then use the powder identical with the blank material that the little magnetic core blank of Mn-Zn ferrite is buried;

2) will be through the Mn-Zn ferrite that step 1) is handled little magnetic core blank sintering in kiln;

3) products obtained therefrom places the vibrating ball mill vibration behind the sintering, again through ultrasonic cleaning, places more than 24 hours, namely obtains the little magnetic core of Mn-Zn ferrite.

Sintering process of the present invention is applicable to the sintering of the Mn-Zn ferrite little magnetic core of size below 10mm, particularly for sintering temperature height, high-conductive manganese-zinc ferrite product that zinc content is high.Can prevent effectively that little magnetic core from distorting when high temperature sintering, and replace with the zinc that load bearing board takes place that yield rate can reach more than 95%.

Embodiment

Be described in further details below in conjunction with the present invention of embodiment.

Embodiment 1

Technology routinely, the little magnetic core blank forming of Mn-Zn ferrite is example with commercial H4.5 * 2.7 * 1.3-JR10K product.

Holding the powder that burns anti-material upper berth one deck and the equal material of the little magnetic core blank of Mn-Zn ferrite, again blank is deposited on the powder before stacking; Because product is very little, the load bearing board of product (1～50,000) the use standard 310 * 310 that per tour is inferior can be to put; To be sprinkling upon above the blank with the powder of the equal material of blank again after having stacked, spread some more, blank is buried.

Sintering: will pile with the load bearing board of powder and blank, and hold to kiln, normal sintering.

Vibration: the product behind the sintering, surface can attach some powder fine particles.Need by vibrating ball mill, the burr that the powder that it is surperficial and moulding produce removes.Because the magnetic core behind the sintering is very hard, vibration can not damage magnetic core.

Product after the vibration is placed more than 24 hours after ultrasonic cleaning, eliminates the stress that vibration produces.The magnet ring series products can use automatic test machine, the delivery of test back; Products such as conventional UF type, EE type can use automatic finishing rolls, the mill processing of arrangement back, as no finishing rolls, because of magnetic core not fragile, manual operations also can, be that efficient is lower slightly.

The product inductance value does not have distortion at 0.4～0.7uH, and product percent of pass is below 95%.

The contrast experiment

With sintering process difference of the present invention be: blank directly is deposited on the load bearing board, also buries without powder.

Contact with load bearing board, and the inductance value of stacking the product of upper epidermis position has only 0.1～0.3uH, the inductance value of the product in mid-way is about 0.6uH, and magnetic core has the part distortion, and product percent of pass has only 30～40%.

Claims (1)

1. little magnetic core sintering process of Mn-Zn ferrite is characterized in that: comprises the steps,

1) on load bearing board, spreads one deck powder identical with the blank material of the little magnetic core of Mn-Zn ferrite earlier, stack the little magnetic core blank of Mn-Zn ferrite then, then use the powder identical with the blank material that the little magnetic core blank of Mn-Zn ferrite is buried;

2) will be through the Mn-Zn ferrite that step 1) is handled little magnetic core blank sintering in kiln;

3) products obtained therefrom places the vibrating ball mill vibration behind the sintering, again through ultrasonic cleaning, places more than 24 hours, namely obtains the little magnetic core of Mn-Zn ferrite.