公开(公告)号：US20240198422A1

公开(公告)日：2024-06-20

申请号：US18288855

申请日：2022-08-24

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Yuewei Cheng ,  Jinfeng Zheng ,  Hongyuan Liang ,  Shun Guo ,  Haiyan Ma ,  Jingyi Zuo ,  Li Zhang ,  Hongjie Qin ,  Tong Liu ,  Ying Wang

IPC: B22F9/20 ,  B22F1/142 ,  B22F1/145

CPC classification number: B22F9/20 ,  B22F1/142 ,  B22F1/145 ,  B22F2201/11 ,  B22F2201/20 ,  B22F2301/20 ,  B22F2998/10 ,  B22F2999/00

Abstract: A method produces tantalum powder by reducing tantalum oxide with an alkaline earth metal. The method includes (1) mixing tantalum oxide with an excessive alkaline earth metal reducing agent, simultaneously mixing at least one alkali metal and/or alkaline earth metal halide accounting for 10-200% of the weight of the tantalum oxide, heating the mixture to a temperature of 700-1200° C. in a furnace filled with inert gas, and soaking so that the tantalum oxide and reducing agent are subjected to a reduction reaction; (2) at the end of soaking, lowering the temperature to 600-800° C., vacuumizing the interior of the furnace to 10 Pa or less, and soaking under the negative pressure so that the excessive magnesium and tantalum powder mixture are separated; (3) thereafter, raising the temperature of the furnace to 750-1200° C. in the presence of inert gas, and soaking so that the tantalum powder is further sintered in the molten salt; (4) then cooling to room temperature and passivating to obtain a mixed material containing halide and tantalum powder; and (5) separating the tantalum powder from the mixture.

公开(公告)号：US20240157437A1

公开(公告)日：2024-05-16

申请号：US18284362

申请日：2022-08-24

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Yuewei Cheng ,  Hongyuan Liang ,  Shun Guo ,  Jinfeng Zheng ,  Haiyan Ma ,  Jingyi Zuo ,  Li Zhang ,  Hongjie Qin ,  Tong Liu ,  Ying Wang

IPC: B22F1/142 ,  B22F1/145

CPC classification number: B22F1/142 ,  B22F1/145 ,  B22F2301/20

Abstract: A method produces tantalum powder. The method includes: (1) uniformly mixing a tantalum powder raw material, metal magnesium and at least one alkali metal and/or alkaline earth metal halide, loading the mixture into a container, and putting the container in a furnace; (2) raising the temperature of the furnace to 600-1200° C. in the presence of inert gas, and soaking; (3) at the end of soaking, lowering the temperature of the furnace to 600-800° C., vacuumizing the interior of the furnace to 10 Pa or less, soaking under the negative pressure so that the excessive metal is separated; (4) thereafter, raising the temperature of the furnace to 750-1200° C. in the presence of inert gas, and soaking so that the tantalum powder is sintered in the molten salt after oxygen reduction; (5) then cooling to room temperature and passivating to obtain a mixed material containing halide and tantalum powder; and (6) separating the tantalum powder from the resulting mixture.

公开(公告)号：US20240150194A1

公开(公告)日：2024-05-09

申请号：US18284211

申请日：2022-08-24

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Shun Guo ,  Jinfeng Zheng ,  Tao Guo ,  Hongyuan Liang ,  Yuewei Cheng ,  Jingyi Zuo ,  Li Zhang ,  Ying Wang ,  Tong Liu ,  Hongjie Qin

IPC: C01G35/00

CPC classification number: C01G35/00 ,  C01P2006/80

Abstract: A low-carbon, high-purity tantalum pentoxide powder has a carbon content of no greater than 15 ppm. A preparation method for the powder includes: (1) adding a fluotantalic acid (H2TaF7) solution into a reaction kettle, controlling the temperature of the reaction kettle at 30-60° C., adding a precipitator until the pH of the reaction solution is 8-10, then stopping introducing ammonia, and aging to obtain a tantalum hydroxide slurry; (2) filtering and washing the slurry obtained in step (1), and then carrying out solid-liquid separation to obtain a tantalum hydroxide filter cake; (3) drying the filter cake obtained in step (2) to obtain white tantalum hydroxide powder; (4) calcining the tantalum hydroxide powder obtained in step (3), crushing and screening the calcined sample to obtain tantalum pentoxide powder; and (5) subjecting the tantalum pentoxide powder obtained in step (4) to heat treatment at a temperature of 1000-1500° C. to obtain the powder.

公开(公告)号：US10737320B2

公开(公告)日：2020-08-11

申请号：US15111632

申请日：2014-02-27

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Zhongxiang Li ,  Yuewei Cheng ,  Xueqing Chen ,  Ting Wang ,  Dejun Shi ,  Zekun Tong ,  Yan Yan ,  Xiaoyu Tian ,  Zhonghuan Zhao

IPC: B22F1/00 ,  B22F9/04 ,  B22F9/02 ,  B22F9/16 ,  C22F1/18 ,  C23G1/00

Abstract: The present invention relates to a high-purity tantalum powder and a preparation method therefore. The tantalum powder has a purity of more than 99.995%, as analyzed by GDMS. Preferably, the tantalum powder has an oxygen content of not more than 1000 ppm, a nitrogen content of not more than 50 ppm, a hydrogen content of not more than 20 ppm, a magnesium content of not more than 5 ppm, and an average particle diameter D50 of less than 25 μm.

公开(公告)号：US10513769B2

公开(公告)日：2019-12-24

申请号：US15125803

申请日：2014-11-03

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Yuewei Cheng ,  Fukun Lin ,  Xueqing Zhang ,  Guoqing Luo ,  Haiyan Ma ,  Yinghui Ma ,  Yanjie Wang ,  Xuanyu Wang ,  Dongjie Zhang

IPC: C22F1/18 ,  B22F9/20 ,  B22F1/00 ,  H01G9/052 ,  B22F3/10 ,  B22F5/00 ,  B22F9/24 ,  C21D3/02 ,  H01G9/00 ,  H01G9/042 ,  H01G9/04

Abstract: The invention relates to the rare metal smelting field, and particularly, the present invention relates to a tantalum powder for preparing capacitors and a process for preparing the tantalum powder, and to a sintered anode prepared from the tantalum powder. As to the tantalum powder as provided by the invention, its primary tantalum powder has a BET of from 3.0 to 4.5 m2/g. After the secondary agglomeration, the tantalum powder has a large particle size. The tantalum powder has an average Fisher sub-sieve size (FSSS) of 1.2 to 3.0 μm wherein as measured with a standard sieve mesh, more than 75% of tantalum powder has a +325-mesh, and a particle size distribution D50 of more than 60 μm, that is, the secondary particle size is high. A resultant capacitor anode prepared by sintering the tantalum powder of the invention at 1200° C. for 20 minutes and then being energized at the voltage of 20 V has the specific capacitance of from 140,000 to 180,000 μFV/g and the residual current of less than 1.0 nA/μFV. Meantime, the invention provides an economical process for making the tantalum powder.

公开(公告)号：US11534830B2

公开(公告)日：2022-12-27

申请号：US16958150

申请日：2017-12-27

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD.

Inventor： Haiyan Ma ,  Hui Li ,  Guoqing Luo ,  Yuewei Cheng ,  Chunxia Zhao ,  Xueqing Chen ,  Zhidao Wang ,  Fukun Lin ,  Guoqi Yang ,  Ning Wang ,  Yinghui Ma ,  Yanjie Wang ,  Lijun Li ,  Honggang Zhang

IPC: B22F9/20 ,  B22F3/10 ,  B22F9/04 ,  B22F1/05 ,  B22F1/142 ,  H01G9/042 ,  C22C1/04 ,  B22F9/24 ,  C22C27/02 ,  H01G9/052

Abstract: A tantalum powder, a tantalum powder compact, a tantalum powder sintered body, a tantalum anode, an electrolytic capacitor and a preparation method for tantalum powder. The tantalum powder contains boron element, and the tantalum powder has a specific surface area of greater than or equal to 4 m2/g; the ratio of the boron content of the tantalum powder to the specific surface area of the tantalum powder is 2˜16; the boron content is measured in weight ppm, and the specific surface area is measured in m2/g; Powder that can pass through a ρ-mesh screen in the tantalum powder accounts for over 85% of the total weight of the tantalum powder, where ρ=150˜170; and the tantalum powder with high CV has a low leakage current and dielectric loss, and good moldability.

公开(公告)号：US09764388B2

公开(公告)日：2017-09-19

申请号：US14763389

申请日：2013-12-10

Applicant: NINGXIA ORIENT TANTALUM INDUSTRY CO., LTD. ,  NATIONAL ENGINEERING RESEARCH CENTER FOR SPECIAL METAL MATERIALS OF TANTALUM AND NIOBIUM

Inventor： Guoqi Yang ,  Aiguo Zheng ,  Yuewei Cheng ,  Yuezhong Ma

IPC: B22F9/04 ,  C22B34/24 ,  H01G9/00 ,  B22F9/20 ,  B22F9/24 ,  C22C1/04 ,  C22C27/02 ,  H01G9/025 ,  H01G9/042 ,  H01G9/052

CPC classification number: B22F9/20 ,  B22F9/04 ,  B22F9/24 ,  C22B34/24 ,  C22C1/045 ,  C22C27/02 ,  H01G9/025 ,  H01G9/042 ,  H01G9/0525

Abstract: A method for preparing a tantalum power of capacitor grade, comprising: solid tantalum nitride is added when potassium fluotantalate is reduced by sodium. The method increases the nitrogen content in the tantalum powder, and at the same time improves the electrical performance of the tantalum powder. The specific capacitance is increased, and the leakage current and loss is improved. The qualification rate of the anode and the capacitor product is also improved. The method is characterized in that the nitrogen in the tantalum nitride diffuses between the particles of the tantalum powder, with substantially no loss, and thus the nitrogen content is accurate and controllable.