CN106756187B - A kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material - Google Patents

A kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material Download PDF

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CN106756187B
CN106756187B CN201611169388.3A CN201611169388A CN106756187B CN 106756187 B CN106756187 B CN 106756187B CN 201611169388 A CN201611169388 A CN 201611169388A CN 106756187 B CN106756187 B CN 106756187B
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rice hulls
powder
porous titanium
pore creating
titanium material
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CN106756187A (en
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贾磊
王新生
吕振林
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Xian University of Technology
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Xian University of Technology
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/08—Alloys with open or closed pores
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1121—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C14/00—Alloys based on titanium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Powder Metallurgy (AREA)

Abstract

The invention discloses a kind of powder metallurgic methods that porous titanium material is prepared with rice hulls pore creating material, including obtaining the rice hulls powder of different-grain diameter size after rice hulls are carried out with acidification, cleaning, crushing, sieve powder, then grinding, compression moulding and its vacuum-sintering after rice hulls powder is mixed with titanium valve, obtain porous titanium material, not only increase the porosity of porous titanium material, compressive strength is increased, meets the requirement of medical treatment or building etc. on porous titanium material；And the present invention prepares more titanium material using biological material rice hulls as pore creating material, and not only manufacturing cost reduces but also production craft step is simple, there is good use value.

Description

A kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material
Technical field
The invention belongs to porous titanium products preparation method for material technical fields, and in particular to a kind of more with the preparation of rice hulls pore creating material The powder metallurgic method of hole titanium material.
Background technology
China is a large agricultural country and Rice Cropping big country, and annual rice hulls yield is about 4 × 107Ton, but it is comprehensive Utilization rate less than 10%, directly burnt or discarded by wherein most rice hulls, and only fraction is used as animal feed, not only Serious waste of resources, and environmental pollution is caused, in terms of the comprehensive utilization of rice hulls, as a kind of cheap biomass Raw material is widely used in regenerative resource, such as prepares cement concrete material by the use of rice hulls as high-performance additives, Using rice hulls as pore creating material processability is excellent, low-cost porous alumina ceramic and clay brick etc.；It uses Pore creating material of the rice hulls as sintered article, not only make use of the byproduct of Grain Trade, but also also add sintered products Added value, for rice hulls after high-temp combustion, a portion organic substance forms hole, the size of rice hulls after burning Kong Yue great that is bigger, being formed during liquid-phase combustion, the influence of intensity are bigger.
Porous material has the characteristics that porosity, thermal conductivity, excellent mechanical performance and biological property become and grinds in recent years The hot spot studied carefully is widely used in fluid filter, catalyst carrier, heat exchanger, thermal insulation, solid oxide fuel cell, The fields such as burner, biomedical implants, since its relative density is low, porosity is high, specific surface area is high, resistance to sudden heating is good Good, thermal mass is low to wait unique performance, and in terms of the preparation for being also employed in the active porous titanium material of object, but some researchers rely on The volatilization of the pore creating materials such as low-melting-point metal such as Ni, Mg and Al prepares porous titanium material, the pore creating material that another part researcher uses Inorganic salt materials, such as potassium chloride, sodium chloride, urea and ammonium hydrogen carbonate, these materials all there are one it is common the characteristics of, fusing point Temperature is low, by high temperature sintering its crystal volatilization is made to generate hole in the base and prepares porous material, so according to porous material Pore creating material granularity can design the elasticity modulus of different porositys, pore structure and POROUS TITANIUM, them is enable to meet application Requirement, but these materials are obtained by industrialized production, and complex process, cost is big, are existed in preparation process certain The problem of.
The content of the invention
The object of the present invention is to provide a kind of powder metallurgic methods that porous titanium material is prepared with rice hulls pore creating material, solve The problem of cost is excessively high in existing porous titanium material preparation process, complex production process.
The technical solution adopted in the present invention is a kind of powder metallurgy that porous titanium material is prepared with rice hulls pore creating material Method comprises the following steps：
Step 1, rice hulls are pre-processed
Step 1.1, suitable rice hulls, stirring and pickling are added in aqueous citric acid solution；
Step 1.2, step 1.1 treated rice hulls are filtered, is placed in stirring and washing 2-3 time in deionized water, filtering Drying；
Step 1.3, step 1.2 treated rice hulls crushed, obtain rice hulls powder after sieve powder；
Step 2, the rice hulls powder in appropriate step 1.2 with titanium valve is mixed, and adds in abrasive body thereto, inserted mixed It is uniformly mixed in powder machine, obtains mixed powder；
Step 3, the mixed powder in step 2 is added in column stainless steel mould, is suppressed using unidirectional oil pressure universal testing machine Shaping, obtains green compact；
Step 4, the green compact in step 3 are placed in vacuum sintering furnace and be sintered, obtain porous titanium material.
It is of the invention to be further characterized in that,
Aqueous citric acid solution is formulated as in step 1.1：The anhydrous citric acid powder of quality 2-4g is added in into volume 150- In the deionized water of 250ml, stir evenly；And the mass ratio of the rice hulls in step 1.1 and anhydrous citric acid powder is 3-5: 1。
45-55 DEG C of temperature, mixing time 20-40min, mixing speed 5-15r/min when being stirred in step 1.1.
Mixing time 5-10min in step 1.2,90-100 DEG C of drying temperature, drying time 50-70min.
The grain size of step 1.3 semilate rice husk powder is in 100-180 μm, 180-250 μm, 250-380 μm or 380-550 μm Any one.
The mass ratio of titanium valve and rice hulls powder is 4.5-5.5 in the step 2:1.
In step 2 abrasive body be zirconium oxide sphere, and with the ratio of grinding media to material 4 of rice hulls powder and titanium valve:1, when mixing the powder time Between be 1.5-2.5h.
The dwell time is 2-5min during compression moulding in step 3.
The vacuum degree of vacuum sintering furnace is 10 in step 4-3Pa。
The beneficial effects of the invention are as follows：A kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material of the present invention By obtaining the rice hulls powder of different-grain diameter size after rice hulls are carried out with acidification, cleaning, crushing, sieve powder, then will Grinding, compression moulding and its vacuum-sintering after rice hulls powder is mixed with titanium valve, obtain porous titanium material, not only increase The porosity of porous titanium material, increases compressive strength, meets the requirement of medical treatment or building etc. on porous titanium material； And the present invention prepares more titanium material using rice hulls as pore creating material, and not only manufacturing cost reduces but also production craft step Simply, there is good use value.
Description of the drawings
Fig. 1 is a kind of flow diagram for the powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material of the present invention；
Fig. 2 is the scanning electron microscope (SEM) photograph of normal titanium valve；
Fig. 3 is the scanning electron microscope (SEM) photograph of embodiment 2 in the present invention；
Fig. 4 is the scanning electron microscope (SEM) photograph of embodiment 3 in the present invention；
Fig. 5 is the relation schematic diagram between the porosity and mechanical property of embodiment 3 in the present invention.
Specific embodiment
The present invention is described in detail with reference to the accompanying drawings and detailed description.
A kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material of the present invention, as shown in Figure 1, including following Step：
Step 1, rice hulls are pre-processed, avoids influence of the impurity to Titanium base
Step 1.1, suitable rice hulls are added in aqueous citric acid solution, in 45-55 DEG C of temperature, speed 5-15r/min Under the conditions of stirring and pickling 20-40min, wherein aqueous citric acid solution is formulated as：The anhydrous citric acid powder of quality 2-4g is added It in the deionized water for entering volume 150-250ml, stirs evenly, and the mass ratio of rice hulls and anhydrous citric acid powder is 3-5:1；
Step 1.2, step 1.1 treated rice hulls are filtered, is placed in stirring and washing 2-3 time in deionized water, filtering Drying, wherein mixing time 5-10min, 90-100 DEG C of drying temperature, drying time 50-70min；
Step 1.3, step 1.2 treated rice hulls crushed, obtain rice hulls powder after sieve powder, rice hulls powder Grain size is any one in 100-180 μm, 180-250 μm, 250-380 μm or 380-550 μm；
Step 2, it is 4.5-5.5 by mass ratio by the rice hulls powder in appropriate step 1.2:1 titanium valve and rice hulls powder Mixing, and abrasive body zirconium oxide sphere is added in thereto, it inserts in mixed powder machine and is uniformly mixed, obtain mixed powder, wherein ratio of grinding media to material 4: 1, it is 1.5-2.5h to mix the powder time；
Step 3, the mixed powder in step 2 is added in column stainless steel mould, is suppressed using unidirectional oil pressure universal testing machine Shaping, pressurize 2-5min obtain green compact；
Step 4, the green compact in step 3 are placed in vacuum degree as 10-3Sintering, obtains porous titanium products in the vacuum sintering furnace of Pa Material.
Embodiment 1
(1) rice hulls pickling processes
The rice hulls of use come from Wuhan meter Chang, and it is 3 to take mass ratio:1 rice hulls and anhydrous citric acid powder, by matter The anhydrous citric acid powder for measuring 2g is added in the deionized water of volume 150ml, stirs evenly to form aqueous citric acid solution, by paddy Shell is placed in aqueous citric acid solution, the stirring and pickling 40min under the conditions of temperature 45 C, speed 5r/min, the rice after filtering acidifying Husk places it in stirring and washing 3 times in deionized water, refilters drying, wherein mixing time 5min, 90 DEG C of drying temperature, Drying time 50min.
(2) pulverization process
The rice hulls being acidified after washing are inserted in pulverizer and are crushed, then screening obtains rice hulls powder, rice hulls powder The grain size at end is 100-180 μm.
(3) grinding and compression moulding
It is 4.5 to take mass ratio:1 titanium valve is mixed with rice hulls powder, and adds in abrasive body zirconium oxide sphere thereto, works as ball Material is than being 4:Mixed powder 1.5h in mixed powder machine is inserted when 1 to be uniformly mixed, and obtains mixed powder；Then mixed powder is added in into column stainless steel mould Interior, using unidirectional oil pressure universal testing machine compression moulding, pressurize 2min obtains green compact.
(4) it is sintered
Green compact are placed in vacuum degree as 10-3Sintering, obtains porous titanium material in the vacuum sintering furnace of Pa.
Embodiment 2
(1) rice hulls pickling processes
The rice hulls of use come from Wuhan meter Chang, and it is 4 to take mass ratio:1 rice hulls and anhydrous citric acid powder, by matter The anhydrous citric acid powder for measuring 3g is added in the deionized water of volume 200ml, stirs evenly to form aqueous citric acid solution, by paddy Shell is placed in aqueous citric acid solution, the stirring and pickling 30min under the conditions of temperature 50 C, speed 10r/min, the rice after filtering acidifying Husk places it in stirring and washing 2 times in deionized water, refilters drying, wherein mixing time 8min, 95 DEG C of drying temperature, Drying time 60min.
(2) pulverization process
The rice hulls being acidified after washing are inserted in pulverizer and are crushed, then screening obtains rice hulls powder, rice hulls powder The grain size at end is 180-250 μm.
(3) grinding and compression moulding
It is 5 to take mass ratio:1 titanium valve is mixed with rice hulls powder, and adds in abrasive body zirconium oxide sphere thereto, when ball material Than for 4:Mixed powder 2h in mixed powder machine is inserted when 1 to be uniformly mixed, and obtains mixed powder；Then mixed powder is added in column stainless steel mould, Using unidirectional oil pressure universal testing machine compression moulding, pressurize 4min obtains green compact.
(4) it is sintered
Green compact are placed in vacuum degree as 10-3Sintering, obtains porous titanium material in the vacuum sintering furnace of Pa.
Embodiment 3
(1) rice hulls pickling processes
The rice hulls of use come from Wuhan meter Chang, and it is 5 to take mass ratio:1 rice hulls and anhydrous citric acid powder, by matter The anhydrous citric acid powder for measuring 4g is added in the deionized water of volume 250ml, stirs evenly to form aqueous citric acid solution, by paddy Shell is placed in aqueous citric acid solution, the stirring and pickling 20min under the conditions of 55 DEG C of temperature, speed 15r/min, the rice after filtering acidifying Husk places it in stirring and washing 3 times in deionized water, refilters drying, wherein mixing time 10min, drying temperature 100 DEG C, drying time 70min.
(2) pulverization process
The rice hulls being acidified after washing are inserted in pulverizer and are crushed, then screening obtains rice hulls powder, rice hulls powder The grain size at end is 380-550 μm.
(3) grinding and compression moulding
It is 5.5 to take mass ratio:1 titanium valve is mixed with rice hulls powder, and adds in abrasive body zirconium oxide sphere thereto, works as ball Material is than being 4:Mixed powder 2.5h in mixed powder machine is inserted when 1 to be uniformly mixed, and obtains mixed powder；Then mixed powder is added in into column stainless steel mould Interior, using unidirectional oil pressure universal testing machine compression moulding, pressurize 5min obtains green compact.
(4) it is sintered
Green compact are placed in vacuum degree as 10-3Sintering, obtains porous titanium material in the vacuum sintering furnace of Pa.
It is respectively that embodiment 2 and embodiment 3 generate as shown in Figure 3-4 as shown in Fig. 2, being the scanned photograph of normal titanium valve POROUS TITANIUM scanned photograph, it can be deduced that, the normal titanium of the void ratio of POROUS TITANIUM in the scanned photograph of embodiment 2 and embodiment 3 The hole bigger of powder, as shown in figure 5, and the porosity maximum of porous titanium material can reach 59.45%, compressive strength maximum energy Reach 70MPa, maximum flexibility mould is 6.36Gpa, meets the requirement of medical treatment or building etc. on porous titanium material；And The present invention prepares more titanium material using biological material rice hulls as pore creating material, and not only manufacturing cost reduces but also production work Skill step is simple, there is good use value.

Claims (4)

1. a kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material, which is characterized in that comprise the following steps：
Step 1, rice hulls are pre-processed
Step 1.1, suitable rice hulls, stirring and pickling are added in aqueous citric acid solution；
45-55 DEG C of temperature, mixing time 20-40min, mixing speed 5-15r/min when wherein stirring；
Step 1.2, step 1.1 treated rice hulls are filtered, is placed in stirring and washing 2-3 times in deionized water, filtering drying；
Step 1.3, step 1.2 treated rice hulls crushed, obtain rice hulls powder after sieve powder；
Wherein the grain size of rice hulls powder is any one in 100-180 μm, 180-250 μm, 250-380 μm or 380-550 μm；
Step 2, the rice hulls powder in appropriate step 1.2 with titanium valve is mixed, and adds in abrasive body thereto, insert mixed powder machine It is interior to be uniformly mixed, obtain mixed powder；
The mass ratio of wherein titanium valve and rice hulls powder is 4.5-5.5:1；
Step 3, the mixed powder in step 2 is added in column stainless steel mould, using unidirectional oil pressure universal testing machine compression moulding, Obtain green compact；The dwell time is 2-5min during compression moulding；
Step 4, the green compact in step 3 are placed in vacuum degree as 10-3Sintering, obtains porous titanium material in the vacuum sintering furnace of Pa.
2. a kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material according to claim 1, feature It is, aqueous citric acid solution is formulated as in the step 1.1：The anhydrous citric acid powder of quality 2-4g is added in into volume In the deionized water of 150-250ml, stir evenly；And the rice hulls in step 1.1 and the mass ratio of anhydrous citric acid powder are 3-5:1。
3. a kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material according to claim 1, feature It is, mixing time 5-10min in the step 1.2,90-100 DEG C of drying temperature, drying time 50-70min.
4. a kind of powder metallurgic method that porous titanium material is prepared with rice hulls pore creating material according to claim 1, feature Be, in the step 2 abrasive body be zirconium oxide sphere, and with the ratio of grinding media to material 4 of rice hulls powder and titanium valve:1, mix the powder time For 1.5-2.5h.
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CN107779640A (en) * 2017-11-01 2018-03-09 成都先进金属材料产业技术研究院有限公司 The preparation method of POROUS TITANIUM
CN111571291B (en) * 2020-05-21 2021-06-29 贵州永红航空机械有限责任公司 Filling material and filling method
CN115582141B (en) * 2021-07-06 2023-08-22 中国石油天然气股份有限公司 Catalyst for slurry cracking and coke gasification thereof and preparation method thereof
CN114455974A (en) * 2022-02-11 2022-05-10 四川墨夏空间艺术设计股份有限公司 Method for manufacturing light ceramic jar cover for wine storage

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Publication number Priority date Publication date Assignee Title
CN102015576A (en) * 2008-02-29 2011-04-13 康宁股份有限公司 Anisotropic porous ceramic article and manufacture thereof
CN103131883A (en) * 2013-03-04 2013-06-05 重庆大学 Preparation method of titanium foam used for cortical bone
CN103752831A (en) * 2013-12-23 2014-04-30 南京高谦功能材料科技有限公司 Porous metal film preparation method

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
CN102015576A (en) * 2008-02-29 2011-04-13 康宁股份有限公司 Anisotropic porous ceramic article and manufacture thereof
CN103131883A (en) * 2013-03-04 2013-06-05 重庆大学 Preparation method of titanium foam used for cortical bone
CN103752831A (en) * 2013-12-23 2014-04-30 南京高谦功能材料科技有限公司 Porous metal film preparation method

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