CN107651954A - 永磁铁氧体预烧料的加工方法 - Google Patents

永磁铁氧体预烧料的加工方法 Download PDF

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CN107651954A
CN107651954A CN201710992387.7A CN201710992387A CN107651954A CN 107651954 A CN107651954 A CN 107651954A CN 201710992387 A CN201710992387 A CN 201710992387A CN 107651954 A CN107651954 A CN 107651954A
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permanent ferrite
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陈国军
吴结华
曹彬
陈远鹏
余东劲
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Anhui Zhong Ci High-Tech Co Ltd
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Abstract

本发明公开了一种永磁铁氧体预烧料的加工方法，包括：A、混料工序：按重量计，取碳酸锶14～16份、铁红100份、二氧化硅0.3～1.5份、碳酸钙0.3～1.5份、硫酸锶0.3～1.5份，投入球磨机中，加入纯水混合均匀；B、料球成型：使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；C、料球预烧：使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；D、振磨工序：经破碎、粗磨、振磨机细磨加工成粒度在3.5‑5.0um的粗粉，即得到永磁铁氧体预烧料。本发明工艺流程合理，工艺条件易于控制，可实现批量加工合格产品。

Description

永磁铁氧体预烧料的加工方法
技术领域
本发明涉及磁性材料的加工方法，具体涉及一种永磁铁氧体预烧料的加工方法。
背景技术
永磁材料作为磁性材料的一个重要组成部分，在电子工业、信息产业、摩托车、电动工具行业、汽车工业等行业发挥着重要的作用。永磁铁氧体材料就是产生磁场的功能材料。永磁铁氧体的生产流程一般包括：配料→预烧→破碎→球磨→制粉→干压磁场成型/干压成型/湿压磁场成型→烧结→机械加工等。
永磁铁氧体预烧料的加工过程实际上是碳酸锶（SrCO3）与铁红（Fe2O3）经过高温下的固相反应充分生成六角形的铁氧体晶粒的过程。固相反应是否完善、充分，晶粒形状是否完整，对材料的质量有很大影响。同时预烧料的优劣在铁氧体磁铁的生产中至关重要，质量差的预烧料是无法生产出高性能铁氧体磁铁。
发明内容
本发明所要解决的技术问题在于提供一种永磁铁氧体预烧料的加工方法，其工艺流程合理，工艺条件易于控制，可实现批量加工合格产品。
为解决上述技术问题，本发明的永磁铁氧体预烧料的加工方法包括以下步骤：
A、混料工序：
按重量计，取碳酸锶14～16份、铁红100份、二氧化硅0.3～1.5份、碳酸钙0.3～1.5份、硫酸锶0.3～1.5份，投入球磨机中，加入纯水混合均匀；
B、料球成型：
使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；
C、料球预烧：
使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；
将成型料球推入加热区，通入天然气和足量空气燃烧，800～950℃条件下加热10分钟；
然后将成型料球推入预烧区，通入天然气和足量空气燃烧，1250±50℃条件下加热90分钟；
降温区设置为减少空气流通的半封闭环境，将成型料球推入降温区将至室温；
D、振磨工序：
经破碎、粗磨、振磨机细磨加工成粒度在3.5-5.0um的粗粉，即得到永磁铁氧体预烧料。
所述步骤A中，铁红纯度＞95%。所述步骤A中，原料的粒度≤1.5um。
所述步骤B中，所得料球水分含量控制在10%以下。
本发明的优点体现在，A、混料均匀，有利于铁红与配料的充分接触，预烧时固相反应充分。B、通过料球成型并设置贯通孔的工艺提高了预烧充分性；C、通过推板窑炉加热，加热区、预烧区、降温区温度和氧气气氛参数不同，从而便于控制生产工艺；D、所得产品经检测，其矫顽力、剩磁等指标均达到要求。
具体实施方式
实施例一
A、混料工序：
取碳酸锶150kg、铁红1000kg、二氧化硅8kg、碳酸钙10kg、硫酸锶5kg，投入球磨机中，加入纯水混合均匀并球磨为1.0um颗粒；
B、料球成型：
使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；所述通孔孔径10毫米；
C、料球预烧：
使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；
将成型料球推入加热区，通入天然气和足量空气燃烧，800～950℃条件下加热10分钟；
然后将成型料球推入预烧区，通入天然气和足量空气燃烧，1250±50℃条件下加热90分钟；
降温区设置为减少空气流通的半封闭环境，将成型料球推入降温区将至室温；
D、振磨工序：
将已经烧结预烧料球经鄂式破碎机破碎、粗磨、振磨机细磨加工成粒度在3.5-5.0um的粗粉，即得到永磁铁氧体预烧料。
实施例二
A、混料工序：
取碳酸锶145kg、铁红1000kg、二氧化硅3kg、碳酸钙8kg、硫酸锶4kg，投入球磨机中，加入纯水混合均匀并球磨为1.0um颗粒；
B、料球成型：
使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；所述通孔孔径10毫米；
C、料球预烧：
使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；
将成型料球推入加热区，通入天然气和足量空气燃烧，800～950℃条件下加热10分钟；
然后将成型料球推入预烧区，通入天然气和足量空气燃烧，1250±50℃条件下加热90分钟；
降温区设置为减少空气流通的半封闭环境，将成型料球推入降温区将至室温；
D、振磨工序：
将已经烧结预烧料球经鄂式破碎机破碎、粗磨、振磨机细磨加工成粒度在3.5-5.0um的粗粉，即得到永磁铁氧体预烧料。
实施例三
A、混料工序：
取碳酸锶140kg、铁红1000kg、二氧化硅5kg、碳酸钙7kg、硫酸锶5kg，投入球磨机中，加入纯水混合均匀并球磨为1.0um颗粒；
B、料球成型：
使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；所述通孔孔径10毫米；
C、料球预烧：
使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；
将成型料球推入加热区，通入天然气和足量空气燃烧，800～950℃条件下加热10分钟；
然后将成型料球推入预烧区，通入天然气和足量空气燃烧，1250±50℃条件下加热90分钟；
降温区设置为减少空气流通的半封闭环境，将成型料球推入降温区将至室温；
D、振磨工序：
将已经烧结预烧料球经鄂式破碎机破碎、粗磨、振磨机细磨加工成粒度在3.5-5.0um的粗粉，即得到永磁铁氧体预烧料。
实施例产品检测指标
本发明的具体实施方式包括但不局限于上述实施例，在不背离本发明精神及其实质的情况下，熟悉本领域的技术人员可根据本发明作出各种相应的改变和变形，但仍然落入本发明的保护范围。

Claims (4)

1.一种永磁铁氧体预烧料的加工方法，包括以下步骤：
A、混料工序：
按重量计，取碳酸锶14～16份、铁红100份、二氧化硅0.3～1.5份、碳酸钙0.3～1.5份、硫酸锶0.3～1.5份，投入球磨机中，加入纯水混合均匀；
B、料球成型：
使用煤球成型机将已混和的原料成型为直径110±10毫米、高度70±10毫米且中间有通孔的料球；
C、料球预烧：
使用推板窑炉对成型料球进行预烧，所述推板窑炉设置有加热区、预烧区、降温区；
将成型料球推入加热区，通入天然气和足量空气燃烧，800～950℃条件下加热10分钟；
然后将成型料球推入预烧区，通入天然气和足量空气燃烧，1250±50℃条件下加热90分钟；
降温区设置为减少空气流通的半封闭环境，将成型料球推入降温区将至室温；
D、振磨工序：
经破碎、粗磨、振磨机细磨加工成粒度在3.5-5.0um的粗粉，即得到永磁铁氧体预烧料。
2.如权利要求1所述的永磁铁氧体预烧料的加工方法，其特征在于：所述步骤A中，铁红纯度＞95%。
3.如权利要求1所述的永磁铁氧体预烧料的加工方法，其特征在于：所述步骤A中，原料的粒度≤1.5um。
4.如权利要求1所述的永磁铁氧体预烧料的加工方法，其特征在于：所述步骤B中，所得料球水分含量控制在10%以下。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108997008A (zh) * 2018-10-12 2018-12-14 哈尔滨理工大学 一种掺杂的锶铁氧体磁性材料及其制备方法
CN112614689A (zh) * 2020-12-25 2021-04-06 中钢集团南京新材料研究院有限公司 一种提高粘结永磁铁氧体磁粉各向异性的方法

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CN112614689A (zh) * 2020-12-25 2021-04-06 中钢集团南京新材料研究院有限公司 一种提高粘结永磁铁氧体磁粉各向异性的方法

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