[go: up one dir, main page]

CN1271004C - Sintering process of superfine pure WC without adhering phase - Google Patents

Sintering process of superfine pure WC without adhering phase Download PDF

Info

Publication number
CN1271004C
CN1271004C CNB2004100680228A CN200410068022A CN1271004C CN 1271004 C CN1271004 C CN 1271004C CN B2004100680228 A CNB2004100680228 A CN B2004100680228A CN 200410068022 A CN200410068022 A CN 200410068022A CN 1271004 C CN1271004 C CN 1271004C
Authority
CN
China
Prior art keywords
sintering
powder
vacuum
power
pure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CNB2004100680228A
Other languages
Chinese (zh)
Other versions
CN1609053A (en
Inventor
黄斌
陈立东
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Jiao Tong University
Original Assignee
Shanghai Jiao Tong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Jiao Tong University filed Critical Shanghai Jiao Tong University
Priority to CNB2004100680228A priority Critical patent/CN1271004C/en
Publication of CN1609053A publication Critical patent/CN1609053A/en
Application granted granted Critical
Publication of CN1271004C publication Critical patent/CN1271004C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Powder Metallurgy (AREA)

Abstract

一种无粘结相超细纯碳化钨的烧结方法,用于粉末冶金及与硬质材料应用领域。本发明以经过真空或惰性气体保存的无粘结相的超细纯WC粉为原材料,将原材料粉在电极用高强度石墨模具中压实后,连同模具一起置于SPS放电等离子烧结装置的上下电极之间,抽取真空使真空度达到5Pa以上后通电升温并在石墨模具的承受极限范围内加压,达到烧结温度后保温,断电冷却后取出试料。真空度达到5Pa以上后通电以平均180℃/min的速度升温,烧结温度为1400-1600℃,保温时间0-8分钟。本发明采用SPS技术直接烧结无粘结相超细纯碳化钨材料,从而克服现有硬质材料的缺点,具有工艺简单,成本低廉,生产周期短,得到性能优越的硬质材料。The invention relates to a sintering method of superfine pure tungsten carbide without binder phase, which is used in the application field of powder metallurgy and hard materials. In the present invention, the superfine pure WC powder without binding phase preserved in vacuum or inert gas is used as the raw material. After the raw material powder is compacted in the high-strength graphite mold for the electrode, it is placed on the upper and lower sides of the SPS discharge plasma sintering device together with the mold. Between the electrodes, draw a vacuum to make the vacuum degree reach more than 5Pa, then turn on the power to heat up and pressurize within the tolerance limit of the graphite mold, keep warm after reaching the sintering temperature, and take out the sample after turning off the power and cooling. After the vacuum degree reaches above 5Pa, it is powered on and the temperature rises at an average speed of 180°C/min, the sintering temperature is 1400-1600°C, and the holding time is 0-8 minutes. The invention adopts SPS technology to directly sinter superfine pure tungsten carbide material without bonding phase, so as to overcome the shortcomings of existing hard materials, and has the advantages of simple process, low cost, short production cycle, and obtains hard materials with superior performance.

Description

The sintering method of superfine pure WC without adhering phase
Technical field
The present invention relates to a kind of sintering method of wolfram varbide, specifically is a kind of sintering method of superfine pure WC without adhering phase.Be used for powder metallurgy and and mechanically resistant material Application Areas.
Background technology
Wolfram varbide (WC) is the most frequently used mechanically resistant material.Because the fusing point of WC is produced utilization in the mode of sintered hard alloys such as WC-Co usually up to 3048K, Co etc. play cohesive action.The interpolation of bonding phases such as Co has not only reduced the hardness of material, and erosion resistance and scale resistance make that also production process is complicated, and owing to causes thermal stresses easily with the difference of the thermal expansivity of WC.In addition, when processing steel part usually, smear metal is bonded at easily influences cutter on the cutter the result of use that exists of phase Co because low melting point bonds, and tiny grain-size helps improving the performance of mechanically resistant material.The normal sintering mode needs Partial Liquid Phase, and some WC grain are dissolved in liquid phase, separates out on other crystal grain then, and the latter is grown up.The particle of original WC powder is thin more, and solubleness and the dissolution rate of WC in liquid phase is big more, and growing up during sintering is serious more, and the normal sintering mode treatment time is long, is difficult to obtain ultra-fine mechanically resistant material.In recent years the SPS discharge plasma sintering technique of Chu Xianing (hereinafter to be referred as the SPS technology) is added to press-powder body test portion by the ON-OFF DC-pulse impression that the particular power source control device is taken place, except the caused sintering promoter action of common electrodischarge machining(E.D.M.) (discharge impact pressure and Jiao Er heating), also effectively utilize the caused sintering promoter action of spark discharge phenomenon (moment produces high-temperature plasma) that produces between impulsive discharge initial stage powder.
Find by prior art documents, " Microstructures of binderlesstungsten carbides sintered by spark plasma sintering process " (Seng I.Cha etc. that people such as Seung I.Cha deliver on " Materials Science andEngineering A " 356 (2003) 381-389, " utilize SPS technology agglomerating not have the microstructure of bonding phase wolfram varbide ", Materials Science and Engineering A, 2003 356 volume 381-389 pages or leaves) literary composition, this article utilizes the SPS technology for the pure WC sintering, by reducing sintering temperature (below 1700 ℃) and shortening sintering time, having suppressed crystal grain grows up unusually, but the starting powder particle diameter is thin more, sintered density is low more, the material hole that the WC particle diameter is thin is more, and the WC median size does not reach the degree of ultra-fine (500nm is following).
Summary of the invention
The objective of the invention is to overcome deficiency of the prior art, a kind of sintering method of superfine pure WC without adhering phase is provided, make it adopt SPS technology direct sintering superfine pure WC without adhering phase material, thereby overcome the shortcoming of existing mechanically resistant material, it is simple to form a kind of technology, with low cost, with short production cycle, the preparation method of the mechanically resistant material of superior performance.
The present invention is achieved by the following technical solutions, the present invention is starting material with the ultra-fine pure WC powder of the nothing bonding phase that process vacuum or rare gas element are preserved, with the starting material powder after electrode is with compacting in the high strength graphite mould, place together with mould between the upper/lower electrode of SPS discharge plasma sintering device, extracting vacuum makes vacuum tightness reach 5Pa above back energising and pressurizes with the speed intensification of average about 180 ℃/min and bearing in the limit range of graphite jig, insulation is 0-8 minute after reaching sintering temperature 1400-1600 ℃, and test portion is taken out in outage cooling back.
Pressuring method can have several: a kind of is and the synchronous different pressure that heats up that promptly with the Kai Shi Noboru pressure simultaneously that heats up, pressure reaches capacity when reaching sintering temperature; Another kind is to remain same pressure; Also can segmentation pressurize, i.e. the heating initial stage is used lower constant pressure, is forced into the limit and maintenance always when shrinking beginning rapidly.
Through observing, analyze and test, the present invention obtained the high-density that the primary particle particle diameter keeps substantially (relative density: 97-100%), high rigidity (2000-2700Hv and 93-96.5HRA) and high-fracture toughness (8-15MPam 1/2) the ultra-fine pure WC bulk material of high-performance.
The present invention utilizes Archimedes's law of buoyancy to measure density.The condition determination of Vickers' hardness is load 20Kg, loads 15 seconds time length.Adopt pressing in method to calculate the fracture toughness property of material.Starting material of the present invention can adopt the pure WC powder of various particle diameters, just particle diameter not simultaneously the performance of optimum sintering condition and gained material to some extent difference (particle diameter spy more is that the performance of mechanically resistant material is good more, but difficult more densification sintering), median size 200nm is the thinnest pure WC (powder) material that can access at present.Even the WC-Co commonly used of bonding phase is arranged, also is difficult to obtain the ultra-fine bulk material that median size reaches the 200nm degree with the normal sintering technology.
Key of the present invention is effective utilization of discharge plasma sintering technique, it has the characteristics such as spark discharge between high speed sintering, surface cleaning effect and powder, the shortcoming that can not effectively suppress the grain growth in the sintering process when high speed sintering has overcome normal sintering, effect of electric field makes the sensitization (surface cleaning) easily of powder particle surface, and " spark discharge between powder " make and can concentrate high energy pulse (high-temperature plasma) in needs intergranular bonded part, is successfully that sintering does not have the deciding factor of the pure WC of high melting point of low melting point bonding phase.
Embodiment
Provide following examples in conjunction with content of the present invention:
Embodiment 1:
With the about 30g of ultra-fine pure WC powder of the about 200nm of median size in the graphite jig of internal diameter 20mm after the compacting, place together with mould between the upper/lower electrode of SPS device, energising heats up and the segmentation pressurization with the speed of about 160 ℃/min after the extracting vacuum, reached after 1400 ℃ of the sintering temperatures insulation 4 minutes, sample is taken out in outage cooling back.The result of scanning electron microscopic observation shows that WC particle diameter and the starting powder particle diameter behind the sintering is consistent.After measured, the relative density of this sample is 97.1%, and hardness is about 2050Hv and 94.1HRA, and fracture toughness property is about 15MPam 1/2
Embodiment 2:
With the about 13g of ultra-fine pure WC powder of the about 200nm of median size in the graphite jig of internal diameter 15mm after the compacting, place together with mould between the upper/lower electrode of SPS device, energising heats up and the segmentation pressurization with the speed of about 150 ℃/min after the extracting vacuum, reached after 1450 ℃ of the sintering temperatures insulation 8 minutes, sample is taken out in outage cooling back.After measured, the relative density of this sample is 98%, and hardness is about 2700Hv and 95HRA, and fracture toughness property is about 9MPam 1/2
Embodiment 3:
With the about 35g of ultra-fine pure WC powder of the about 200nm of median size in the graphite jig of internal diameter 20mm after the compacting, place together with mould between the upper/lower electrode of SPS device, energising heats up and the segmentation pressurization with the speed of about 180 ℃/min after the extracting vacuum, reached after 1430 ℃ of the sintering temperatures insulation 4 minutes, sample is taken out in outage cooling back.The result of X-ray diffraction test shows that this sample still is made of mutually single WC.The result of scanning electron microscopic observation shows WC particle diameter and the starting powder particle diameter basically identical behind the sintering.After measured, the relative density of this sample is 98.1%, and hardness is about 2600Hv and 96.1HRA, and fracture toughness property is about 11MPam 1/2
Embodiment 4:
With the about 11g of ultra-fine pure WC powder of the about 200nm of median size in the graphite jig of internal diameter 15mm after the compacting, the SPS device of packing into, energising heats up and the segmentation pressurization with the speed of about 150 ℃/min after the extracting vacuum, reaches after 1500 ℃ of the sintering temperatures insulation 4 minutes.The result of X-ray diffraction test shows that this sample still is made of mutually single WC.The result of scanning electron microscopic observation shows that the WC particle diameter ratio starting powder particle diameter of this sample grows up to some extent, but not clearly.After measured, the relative density of this sample is 99.6%, and hardness is about 2550Hv, and fracture toughness property is about 10MPam 1/2
Embodiment 5:
With the about 13g of ultra-fine pure WC powder of the about 200nm of median size in the graphite jig of internal diameter 15mm after the compacting, the SPS device of packing into, energising heats up and the segmentation pressurization with the speed of about 150 ℃/min after the extracting vacuum, reaches after 1600 ℃ of the sintering temperatures insulation 0 minute.The result of X-ray diffraction test shows that this sample still is made of mutually single WC.After measured, the density of this sample is 15.6g/cm 3(relative density reaches 100%), hardness is about 2600Hv, and fracture toughness property is about 10.5MPam 1/2

Claims (1)

1、一种无粘结相超细纯碳化钨的烧结方法,其特征在于,以经过真空或惰性气体保存的无粘结相的超细纯WC粉为原材料,将原材料粉在电极用高强度石墨模具中压实后,连同模具一起置于SPS放电等离子烧结装置的上下电极之间,抽取真空使真空度达到5Pa以上后通电升温并在石墨模具的承受极限范围内加压,达到烧结温度后保温,断电冷却后取出试料,所述的真空度达到5Pa以上后通电以平均180℃/min的速度升温,烧结温度为1400-1600℃,保温时间0-8分钟。1. A sintering method for superfine pure tungsten carbide without a binding phase, characterized in that the ultrafine pure WC powder without a binding phase preserved in a vacuum or an inert gas is used as a raw material, and the raw material powder is placed in an electrode with a high-strength After being compacted in the graphite mold, place the mold together with the upper and lower electrodes of the SPS discharge plasma sintering device, draw a vacuum to make the vacuum degree above 5Pa, then turn on the power to heat up and pressurize within the tolerance limit of the graphite mold, and reach the sintering temperature Keep warm, take out the sample after turning off the power and cooling. After the vacuum degree reaches above 5Pa, turn on the power and heat up at an average speed of 180°C/min. The sintering temperature is 1400-1600°C, and the holding time is 0-8 minutes.
CNB2004100680228A 2004-11-11 2004-11-11 Sintering process of superfine pure WC without adhering phase Expired - Fee Related CN1271004C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB2004100680228A CN1271004C (en) 2004-11-11 2004-11-11 Sintering process of superfine pure WC without adhering phase

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB2004100680228A CN1271004C (en) 2004-11-11 2004-11-11 Sintering process of superfine pure WC without adhering phase

Publications (2)

Publication Number Publication Date
CN1609053A CN1609053A (en) 2005-04-27
CN1271004C true CN1271004C (en) 2006-08-23

Family

ID=34765142

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2004100680228A Expired - Fee Related CN1271004C (en) 2004-11-11 2004-11-11 Sintering process of superfine pure WC without adhering phase

Country Status (1)

Country Link
CN (1) CN1271004C (en)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9056799B2 (en) 2010-11-24 2015-06-16 Kennametal Inc. Matrix powder system and composite materials and articles made therefrom
CN102925728B (en) * 2011-08-12 2014-11-19 中国科学院上海硅酸盐研究所 A kind of preparation method of nanometer tungsten carbide cemented carbide without bonding phase
CN103567440A (en) * 2013-08-15 2014-02-12 厦门虹鹭钨钼工业有限公司 Preparation method for tungsten carbide target material for film coating of oil exploration drill bit
CN104232967B (en) * 2014-10-10 2017-01-18 台州学院 Method for preparing low binder phase wolfram carbide hard alloy
CN105088044B (en) * 2015-09-30 2017-04-05 株洲水箭硬质合金有限责任公司 A kind of preparation method of the mutually superhard level hard metal article of nanometer of soap-free emulsion polymeization
CN107522490A (en) * 2016-06-20 2017-12-29 张家港市华舰五金工具有限公司 The preparation method of tungsten carbide ceramics material
CN106116582B (en) * 2016-06-27 2017-06-16 上海海事大学 A kind of sintering method of cobalt-free tungsten carbide
CN106810260B (en) * 2017-01-13 2020-04-24 台州学院 Preparation method of tungsten carbide-based non-binding phase hard alloy
CN107620049B (en) * 2017-09-01 2019-11-05 北京安泰六九新材料科技有限公司 A kind of preparation method of soap-free emulsion polymeization phase pure WC target
CN108033790A (en) * 2017-12-21 2018-05-15 洛阳名力科技开发有限公司 A kind of preparation method of non-bond cemented carbide
CN108145302A (en) * 2017-12-22 2018-06-12 合肥工业大学 A kind of SPS diffusion welding methods of WC hard alloy of the same race
CN108276001A (en) * 2018-01-09 2018-07-13 中国海洋石油集团有限公司 A kind of super abrasive Talide discharge plasma sintering method
CN108165859B (en) * 2018-01-22 2019-08-30 合肥工业大学 A SPS sintering method of large-scale pure tungsten carbide cemented carbide without binder phase
CN109692955A (en) * 2019-03-04 2019-04-30 郑州大学 A kind of pure WC hard alloy preparation method and pure WC hard alloy
CN112250442B (en) * 2020-09-30 2021-08-24 北京科技大学 A kind of preparation method of high strength and toughness unbonded phase nanocrystalline cemented carbide
CN120192164B (en) * 2025-05-27 2025-09-02 安徽尚欣晶工新材料科技有限公司 Large-size optical mold material for aspheric glass lens molding and preparation method thereof

Also Published As

Publication number Publication date
CN1609053A (en) 2005-04-27

Similar Documents

Publication Publication Date Title
CN1271004C (en) Sintering process of superfine pure WC without adhering phase
CN101684520B (en) Ultrasonic-assisted densification device
Guo et al. Rapid diffusion bonding of WC-Co cemented carbide to 40Cr steel with Ni interlayer: effect of surface roughness and interlayer thickness
Wang et al. Microstructure and mechanical properties of (Ti, W) C cermets prepared by ultrafast spark plasma sintering
CN106424741B (en) SiC particulate enhances intermetallic compound base laminar composite Ti/Al3The preparation method of Ti
Yin et al. Improvement in microstructure and mechanical properties of Ti (C, N) cermet prepared by two-step spark plasma sintering
Ali et al. Investigation of Boron addition and compaction pressure on the compactibility, densification and microhardness of 316L Stainless Steel
CN106116582A (en) A kind of sintering method of tungsten carbide without cobalt
CN110541151A (en) Polycrystalline cubic boron nitride composite sheet and preparation method thereof
CN103243252A (en) Binder-phase wolfram-carbide (WC) hard alloy and preparation method thereof
CN107287461B (en) A kind of Ultra-fine Grained high performance Ti (C, N)-TiB2- WC-TaC composite cermets cutter and preparation method
CN113106314B (en) Core-shell structure TiB2Base cermet and method for preparing same
Xue et al. Microstructure, mechanical property and cutting performance of (Ti, W) C/Mo/Co/Ni cermet tool material prepared by spark plasma sintering and high frequency induction heating
CN102021473B (en) A kind of preparation method of Fe3Al-Al2O3 composite material
CN114055010A (en) A copper-based alloy brazing material containing trace Ge, preparation method and brazing method thereof
Kim et al. Mechanical properties of binderless tungsten carbide by spark plasma sintering
Liu et al. Microstructures and interfacial quality of diffusion bonded TC21 titanium alloy joints
CN115652166B (en) Superhard hard alloy material for ultrahigh-pressure water jet knife and preparation method thereof
CN115138849B (en) Preparation method of binding phase-free hard alloy cutter material
Xiao et al. Microstructure and mechanical properties of powder metallurgy Ti-Al-Mo-V-Ag alloy
CN106810260B (en) Preparation method of tungsten carbide-based non-binding phase hard alloy
Chang et al. Effects of vacuum sintering, HIP and HP treatments on the microstructure, mechanical and electrical properties of Cr70Cu30 alloys
Fukumoto et al. Fabrication of composite material using alumina agglomerated sludge and aluminum powder by spark plasma sintering
Ye et al. Microstructure and shear strength of the brazed joint of Ti (C, N)-based cermet to steel
Brookes Making hardmetal even harder with dispersed cBN

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20060823

Termination date: 20091211