CN101468391B - Mixing method of iron-based powder for powder metallurgy - Google Patents
Mixing method of iron-based powder for powder metallurgy Download PDFInfo
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- CN101468391B CN101468391B CN 200710159252 CN200710159252A CN101468391B CN 101468391 B CN101468391 B CN 101468391B CN 200710159252 CN200710159252 CN 200710159252 CN 200710159252 A CN200710159252 A CN 200710159252A CN 101468391 B CN101468391 B CN 101468391B
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- 239000000843 powder Substances 0.000 title claims abstract description 77
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims abstract description 37
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 27
- 238000004663 powder metallurgy Methods 0.000 title claims abstract description 17
- 238000002156 mixing Methods 0.000 title abstract description 14
- 238000001035 drying Methods 0.000 claims abstract description 24
- 239000002184 metal Substances 0.000 claims abstract description 18
- 229910052751 metal Inorganic materials 0.000 claims abstract description 18
- 239000011159 matrix material Substances 0.000 claims abstract description 16
- 239000000314 lubricant Substances 0.000 claims abstract description 13
- 229910052755 nonmetal Inorganic materials 0.000 claims abstract description 13
- 239000000853 adhesive Substances 0.000 claims abstract description 10
- 230000001070 adhesive effect Effects 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 10
- 230000008569 process Effects 0.000 claims abstract description 10
- 239000007789 gas Substances 0.000 claims abstract description 7
- 239000011261 inert gas Substances 0.000 claims abstract description 5
- 239000000203 mixture Substances 0.000 claims description 16
- 239000011230 binding agent Substances 0.000 claims description 14
- 239000002245 particle Substances 0.000 claims description 6
- 238000012216 screening Methods 0.000 claims description 6
- 239000002202 Polyethylene glycol Substances 0.000 claims description 5
- 239000003595 mist Substances 0.000 claims description 5
- 229920001223 polyethylene glycol Polymers 0.000 claims description 5
- 206010013786 Dry skin Diseases 0.000 claims description 2
- 238000001816 cooling Methods 0.000 claims description 2
- 230000007246 mechanism Effects 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims description 2
- 238000012856 packing Methods 0.000 claims description 2
- 238000010348 incorporation Methods 0.000 claims 1
- 230000001681 protective effect Effects 0.000 abstract description 9
- 238000011031 large-scale manufacturing process Methods 0.000 abstract description 5
- 230000003647 oxidation Effects 0.000 abstract description 4
- 238000007254 oxidation reaction Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract 3
- 238000009792 diffusion process Methods 0.000 abstract 1
- 238000004806 packaging method and process Methods 0.000 abstract 1
- 230000002265 prevention Effects 0.000 abstract 1
- 238000007873 sieving Methods 0.000 abstract 1
- 239000011812 mixed powder Substances 0.000 description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 229910002804 graphite Inorganic materials 0.000 description 7
- 239000010439 graphite Substances 0.000 description 7
- 239000000428 dust Substances 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 238000005204 segregation Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 238000010237 hybrid technique Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000005012 migration Effects 0.000 description 3
- 238000013508 migration Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 230000009969 flowable effect Effects 0.000 description 2
- 238000005304 joining Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 229920005596 polymer binder Polymers 0.000 description 2
- 239000002491 polymer binding agent Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
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Abstract
The invention discloses a mixing method of iron-based powder used in powder metallurgy. The mixing method is characterized by comprising: preparing raw material powder (except lubricant) in matrix iron powder according to formula; adding at least one kind or more than one kind of metal powder and nonmetal powder according to a proportion no more than 25 percent into the raw material powder; meanwhile, adding adhesive powder of 0.001 to 1.0 percent by mass fraction into the raw material powder; mixing the materials in a biconical mixing device or a conical mixing device for 20 to 60 minutes and drying the materials in drying equipment filled with protective inert gases or reducing gases at a temperature of between 200 and 600 DEG C; and then, sieving the materials and adding the materials in the biconical mixing device or the conical mixing device again (adding lubricant), and packaging the materials after even mixing. The mixing method takes the double effects of adhesion and diffusion and transfer as basic principle, and can realize large-scale production under the conditions of less consumption of the prior adhesive and protective atmosphere; moreover, the mixing method has the characteristics of simple process, common equipment, low cost, convenient use, effective increase of powder product density and prevention of powder oxidation, and the like.
Description
Technical field
The present invention relates to a kind of mixed method of iron-based powder for powder metallurgy.
Background technology
The mixing of iron-based powder is one critical process during sintered metal product is produced, it is that at least a above metal, the non-metal powders such as the Cu of certain particle diameter, Ni, graphite and lubricant are added to take water-atomized iron powder or reduced iron powder in the iron-based powder of matrix, thereby improves the final performance of sintered metal product behind suppression performance and the sintering.
In actual production, it fully evenly is very difficult something that the mixing of powder reaches.Mixed iron-based powder is because processes such as placement, transportation and fillings, and the metal of adding, non-metal powder produce segregation, causes composition, performance and the overall dimensions of the sintered metal product produced to produce fluctuation.In addition, owing to contain more fine particle, make the poor fluidity of powder, filling mould difficulty.Also can produce the dust pollution environment in the use procedure.
For the problems referred to above, the relatively advanced Sweden of powder metallurgy, Canada and Japan and other countries have successively been developed powder metallurgy adhesive treatment hybrid technique in the world, its cardinal principle is take iron-based powder as matrix, adopts binding agent that metal, non-metal powder are bonded in (referring to Fig. 1) on the matrix powder.The problem of the sintered metal product composition that the iron-based powder segregation caused after the appearance of these techniques had solved and mixed, performance and overall dimensions fluctuation has also reduced airborne dust, thus use powder clean environment many.Patent CN1373696A and CN1370645A have announced two kinds of mixed methods.But owing to used complicated technique, special equipment and several polymer-binders, flowable, make the output investment ratio that reaches large-scale production larger, cause the mixed-powder cost higher, be unfavorable for promoting.In the bonding process, be heated in addition the possibility that Powder Oxidation is arranged about 150 ℃, can affect the mixed-powder performance.In a word, because complex process, special production equipment and problems such as several polymer-binders, flowable, make this popularization that product properties behind pressing process and the sintering is improved the mixed-powder that produces contribution run into serious hindrance.
Summary of the invention
The objective of the invention is to bond and spreading, move double action is basic principle; provide a kind of with simple technique; conventional equipment; the situation of using less conventional binders to exist at protective atmosphere namely can reach the mixed method of the iron-based powder for powder metallurgy of large-scale production; the problem of powder metallurgy composition, performance and the overall dimensions fluctuation of using this method can effectively solve equally mixed iron-based powder segregation to cause has also reduced the pollution of airborne dust to environment.
Purpose of the present invention realizes like this:
Press formulated material powder (except lubricant) in the matrix iron powder; at least one or more metals, non-metal powder add to be no more than 25% ratio; the adhesive powder that adds simultaneously 0.001%~1.0% mass fraction; in bipyramid blender or tapered blender, mixed 20~60 minutes, then have protectiveness inert gas optimal selection N
2Or reducibility gas (H
2And N
2Mist) drying equipment in after 200~600 ℃ of dryings, through screening again enter in bipyramid blender or the tapered blender add mix lubricant evenly after packing.
Above-mentioned said by the formulated material powder, the granularity selection that comprises the granularity selection of matrix iron powder and the metal that will add, nonmetal, adhesive powder, the matrix iron powder is selected the following powder of maximum particle diameter 200 μ m, the metal that adds, the nonmetal and following powder of adhesive powder selection maximum particle diameter 75 μ m, the special preferred polyethylene glycol of binding agent etc.Employed drying equipment is a kind of continuous pan feeding and discharging, simultaneously the mechanism of heat drying function and cooling down function is arranged, and namely can heat mixed-powder and again can the mixed-powder that drying is good be cooled to room temperature or near room temperature.The protective gas that passes into is inert gas or reducibility gas, abides by the optimum form that passes into and powder 5~30m per ton
3/ hour flow, the dry time was by 30~120 minutes/ton powder.
Characteristics of the present invention comprise the double action of binding agent bonding and diffusive migration, binding agent is bonded in metal, the non-metal powder that adds on the matrix iron powder surface, form cluster of grains, the metal of interpolation, nonmetal diffusive migration are also arranged to matrix iron powder surface, form cluster of grains.Reduce so to greatest extent the free state of the powder that adds, also exist simultaneously under binding agent bonding and the diffusive migration double action, the mutual bonding of tiny iron matrix powder particles forms cluster of grains.Although added tiny metal; non-metal powder; but the fine particle ratio significantly reduces in the mixed-powder through making after the inventive method processing; and exist with the formation of larger-size cluster of grains; efficiently solve the powder composition that mixed iron-based grain end segregation causes; the fluctuation problem of performance and size; reduced simultaneously the pollution of airborne dust to environment owing to the cluster of grains size is larger; although measure the bond effect of iron-based powder after mixing; so far there is not the generally acknowledged quantitative contrast of method and apparatus; but the iron base powder mixture end of making by this method is for the production of auto parts such as tooth hub; the compositions such as valve seat and family's electrical accessory; performance and size fluctuation are all in user's claimed range; particularly because technique is simple; use the conventional equipment of domestic procurement; traditional binding agent can form large-scale production; the import mixed-powder that compares same recipe, market price low 20%~40%.
Advantage of the present invention comprises that simple technique and conventional equipment, the less conventional binders of use can reach large-scale production; can effectively avoid mixed Powder Oxidation because protective atmosphere exists simultaneously, use the density of less binding agent Effective Raise pulverulent product.The performance of mixed-powder reaches same kind of products at abroad, is convenient to penetration and promotion.The present invention has following characteristics with the foreign technology ratio:
1. technique is simple, conventional equipment, and cost is low; 2. the conventional binders of buying easy to use, and consumption is about 50%~80% of external consumption, but Effective Raise pulverulent product density; 3. use protective atmosphere to prevent Powder Oxidation.
Description of drawings
Fig. 1 is the hybrid technique flow chart of existing iron-based powder for powder metallurgy;
Fig. 2 is the hybrid technique flow chart of iron-based powder for powder metallurgy of the present invention.
The specific embodiment
Embodiment 1:
The present invention describes specific embodiment so that mix to add mass fraction be respectively 1.5%Cu, 0.6% graphite and 0.75% lubricant in the water-atomized iron powder as example.
With granularity less than the Cu of 75 μ m, the granularity graphite less than 20 μ m, joining granularity by formula rate produces among the water-atomized iron powder FSY200.30 less than 180 μ m matrix Anshan iron and steel plants, add simultaneously the granularity of 0.3% mass fraction in double cone mixer, to mix 60 minutes less than 20 μ m binding agent polyethylene glycol, enter continuously in the drying equipment under 300 ℃ baking temperature, use the H of 75% volume fraction
2It is powder 20m per ton that the mist of+25% volume fraction is done the protective atmosphere flow
3/ hour, carry out drying with 90 minutes rate of drying of powder per ton, continuous drying powder out is forced to be cooled to room temperature or near room temperature in system, reuse the mix lubricant that blender adds the formula rate requirement simultaneously and can pack in 60 minutes behind screening process.
Embodiment 2:
The present invention describes specific embodiment so that mix to add mass fraction be respectively 1.0%Ni, 1.5%Cu, 0.6% graphite and 0.75% lubricant in the water-atomized iron powder as example.
With granularity less than Ni, the Cu of 45 μ m, the granularity graphite less than 20 μ m, joining granularity by formula rate produces among the water-atomized iron powder FSY200.30 less than 180 μ m matrix Anshan iron and steel plants, add simultaneously the granularity of 0.2% mass fraction in double cone mixer, to mix 60 minutes less than 20 μ m binding agent polyethylene glycol, enter continuously in the drying equipment under 250 ℃ baking temperature, use the H of 75% volume fraction
2It is powder 10m per ton that the mist of+25% volume fraction is done the protective atmosphere flow
3/ hour, carry out drying with 90 minutes rate of drying of powder per ton, continuous drying powder out is forced to be cooled to room temperature or near room temperature in system, reuse the mix lubricant that blender adds the formula rate requirement simultaneously and can pack in 60 minutes behind screening process.
Embodiment 3:
The present invention describes specific embodiment so that mix to add mass fraction be respectively 6.0%Co, 1.5%Ni, 4.0%Mo, 1.5%Cu, 0.7% graphite and 0.80% lubricant in the water-atomized iron powder as example.
With granularity less than the above-mentioned metal of 75 μ m and alloy, granularity less than the graphite of 20 μ m, join granularity by formula rate and produce among the water-atomized iron powder FSY200.30 less than 180 μ m matrix Anshan iron and steel plants, add simultaneously the granularity of 0.5% mass fraction in double cone mixer, to mix 60 minutes less than 20 μ m binding agent polyethylene glycol, enter continuously in the drying equipment under 400 ℃ baking temperature, use the H of 75% volume fraction
2It is powder 20m per ton that the mist of+25% volume fraction is done the protective atmosphere flow
3/ hour, carry out drying with 90 minutes rate of drying of powder per ton, continuous drying powder out is forced to be cooled to room temperature or near room temperature in system, reuse the mix lubricant that blender adds the formula rate requirement simultaneously and can pack in 60 minutes behind screening process.
Claims (7)
1. the mixed method of an iron-based powder for powder metallurgy; it is characterized in that: press the formulated material powder in the matrix iron powder; more than one metals and non-metal powder are added to be no more than 25% ratio; the adhesive powder that adds simultaneously 0.001%~1.0% mass fraction; in tapered blender, mix; then in the drying equipment with protectiveness inert gas or reducibility gas with after 200~600 ℃ of dryings, through screening again enter in the tapered blender add mix lubricant evenly after packing.
2. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1, it is characterized in that: by the formulated material powder, the granularity selection that comprises the granularity selection of matrix iron powder and the metal that will add, nonmetal, adhesive powder, the matrix iron powder is selected the following powder of particle diameter 200 μ m, the metal of interpolation, the nonmetal and following powder of adhesive powder selection particle diameter 75 μ m.
3. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1 and 2, it is characterized in that: material powder and adhesive powder, the incorporation time in tapered blender are 20~60 minutes.
4. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1 and 2 is characterized in that: comprise continuous pan feeding and drawing mechanism in the drying equipment, heat drying apparatus and device for cooling.
5. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1 and 2, it is characterized in that: the protectiveness inert gas is N
2, reducibility gas is H
2And N
2Mist, the gas flow that passes into is by powder per ton 5~30m per hour
3, the dry time was pressed powder per ton 30~120 minutes.
6. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1 and 2, it is characterized in that: binding agent is polyethylene glycol.
7. the mixed method of a kind of iron-based powder for powder metallurgy according to claim 1 and 2, it is characterized in that: continuous drying powder out is forced to be cooled to room temperature or near room temperature in system, reuses the mix lubricant that tapered blender adds the formula rate requirement simultaneously and can pack in 20~60 minutes behind screening process.
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CN102069187B (en) * | 2011-03-01 | 2012-09-19 | 杭州寰宇粉体科技有限公司 | Mixing method of iron-based powder metallurgy bonding powder |
CN102233425A (en) * | 2011-07-22 | 2011-11-09 | 浙江中平粉末冶金有限公司 | Powder metallurgy formula and process |
CN103394686B (en) * | 2013-07-25 | 2016-06-29 | 莱芜钢铁集团有限公司 | A kind of two-part dry mixing methods of P/m Iron Base mixed powder |
CN105234390A (en) * | 2015-10-20 | 2016-01-13 | 江门市前通粉末冶金厂有限公司 | Material stirring method for powder metallurgy |
CN106825541A (en) * | 2016-12-26 | 2017-06-13 | 有研粉末新材料(北京)有限公司 | A kind of preparation method of bond powders |
CN107321996B (en) * | 2017-06-26 | 2024-01-19 | 安泰(霸州)特种粉业有限公司 | Closed continuous post-treatment system for metal powder |
CN107900361B (en) * | 2017-11-23 | 2019-10-18 | 北京科技大学 | A device and method for high-throughput research and preparation of iron-based powder metallurgy products |
CN114178522A (en) * | 2021-09-06 | 2022-03-15 | 辽宁晟钰金属制品制造有限公司 | Method for preparing iron-based premixed powder |
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---|---|---|---|---|
CN1319468A (en) * | 2001-01-04 | 2001-10-31 | 中南大学 | Method for making warm-pressing iron powder |
CN1759960A (en) * | 2005-10-28 | 2006-04-19 | 合肥波林新材料有限公司 | Warm processing powdered iron, and preparation method |
CN2835914Y (en) * | 2005-08-06 | 2006-11-08 | 天水华圆制药设备科技有限责任公司 | Microwave vacuum continuous drying machine with double drying chambers |
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2007
- 2007-12-28 CN CN 200710159252 patent/CN101468391B/en active Active
Patent Citations (3)
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---|---|---|---|---|
CN1319468A (en) * | 2001-01-04 | 2001-10-31 | 中南大学 | Method for making warm-pressing iron powder |
CN2835914Y (en) * | 2005-08-06 | 2006-11-08 | 天水华圆制药设备科技有限责任公司 | Microwave vacuum continuous drying machine with double drying chambers |
CN1759960A (en) * | 2005-10-28 | 2006-04-19 | 合肥波林新材料有限公司 | Warm processing powdered iron, and preparation method |
Non-Patent Citations (1)
Title |
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Effective date of registration: 20170406 Address after: Lingshan Hongqi Road 114042 Anshan city of Liaoning Province, Lishan District No. 9 Patentee after: Anshan Iron and steel (Anshan) metallurgical powder Co., Ltd. Address before: Anshan City, Liaoning province 114031 Lishan District Jianguo Road 40 A Patentee before: Angang Heavy Machinery Co., Ltd. |