Method of producing MnZn-base ferrite
US7713465B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2008 |
| Grant date | May 11, 2010 |
| Priority date | — |
| Expiry date | Mar 21, 2028 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2235/6584
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Provided is a process for producing a MnZn-base ferrite comprising: firing a compacted raw material to produce the MnZn-base ferrite, wherein the firing comprises, in the following order: a heating phase comprising gradually bringing a firing temperature from room temperature up to a maximum temperature; a maximum temperature holding phase comprising maintaining the maximum temperature for a period of time, wherein a partial pressure of oxygen (p2) at the maximum temperature holding phase is greater than an equilibrium partial pressure of oxygen (p1) as follows: p2>p1, wherein the equilibrium partial pressure of oxygen (p1) is represented by the following equation: log(p1)=log(PO2)=a−b/T, wherein PO2 is measured in a unit of %, and T is measured in a unit of absolute temperature K; and a cooling phase comprising gradually bringing the maximum temperature down to near room temperature, wherein a partial pressure of oxygen (p3) at the cooling phase is operated at an equilibrium partial pressure of oxygen based on the equation log(p3)=a−b/T.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.