CN106702257A - Cast iron piston ring and preparation method thereof - Google Patents

Cast iron piston ring and preparation method thereof Download PDF

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Publication number
CN106702257A
CN106702257A CN201611165025.2A CN201611165025A CN106702257A CN 106702257 A CN106702257 A CN 106702257A CN 201611165025 A CN201611165025 A CN 201611165025A CN 106702257 A CN106702257 A CN 106702257A
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CN
China
Prior art keywords
iron
cast
inovulant
analysis
piston ring
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Pending
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CN201611165025.2A
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Chinese (zh)
Inventor
韦祖旺
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Guangxi University
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Guangxi University
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Priority to CN201611165025.2A priority Critical patent/CN106702257A/en
Publication of CN106702257A publication Critical patent/CN106702257A/en
Pending legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/10—Cast-iron alloys containing aluminium or silicon
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/10—Making spheroidal graphite cast-iron
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/08—Making cast-iron alloys
    • C22C33/10—Making cast-iron alloys including procedures for adding magnesium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/04—Cast-iron alloys containing spheroidal graphite
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/0084—Pistons  the pistons being constructed from specific materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2201/00—Metals
    • F05C2201/04—Heavy metals
    • F05C2201/0433—Iron group; Ferrous alloys, e.g. steel
    • F05C2201/0436—Iron
    • F05C2201/0439—Cast iron
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Abstract

The invention discloses a cast iron piston ring and a preparation method of the piston ring. The cast iron piston ring comprises, by weight percent, 2.9% to 3.3% of C, 2.2% to 2.4% of Si, 0.8% to 1.1% of Mn, 0.04% to 0.06% of B, 0.3% to 0.45% of P, smaller than or equal to 0.08% of S and the balance Fe. The preparation method comprises material preparation, preheating, smelting, quick analysis on-the-spot sample, final deoxidation, ductile processing, inoculation and casting. The method is simple in smelting process, through control over the adding amount of carbon, silicon and boron in cast iron and spheroidizing, high-performance antifriction nodular cast iron can be casted, meanwhile, production cost is reduced, and the method is particularly suitable for casting the piston ring.

Description

A kind of cast-iron piston ring and preparation method thereof
Technical field
The present invention relates to the production technical field of ferrous metal, especially a kind of cast-iron piston ring and preparation method thereof.
Background technology
China is begun to produce spheroidal graphite cast-iron from nineteen fifty, and abundant rare earth resources have been developed since adding for the seven's+, Therefore the unique Rare-earth Elements Treated Nodular Iron of China has been developed on the basis of magnesium spheroidal graphite cast-iron, as important founding materials.Boracic Spheroidal graphite cast-iron is a kind of antifriction material of function admirable, it have hardness very high and extension casting service life the characteristics of. Need to only add boron, matrix hardly to change in cast iron containing boron spheroidal cast iron, simply occur one in austenite Divide boron-carbide.Aobvious Cheng hardness HV=1100 higher due to boron-carbide or so, therefore Wear vesistance is improve, while boron carbon Compound is uniformly distributed in the base, so not bringing many difficulties to processing characteristics.Therefore, boracic anti-attrition spheroidal graphite cast-iron is developed To extend the service life of casting.
The content of the invention
It is an object of the present invention to regarding to the issue above, a kind of cast-iron piston ring and preparation method thereof is proposed, by control The addition of carbon in cast iron, silicon and boron and spheroidising, cast out high-performance anti-attrition spheroidal graphite cast-iron.
The technical solution adopted for the present invention to solve the technical problems is：C2.9~3.3%, Si2.2~2.4%, Mn0.8~ 1.1%th, B0.04~0.06%, P0.3~0.45%, S≤0.08%, balance of Fe.
A kind of method for preparing cast-iron piston ring, including following several steps：
The first step：Dispensing：By steel scrap, foundry returns, the pig iron, ferromanganese, ferrosilicon, pure boron press C2.9~3.3%, Si2.2~2.4%, Mn0.8~1.1%, B0.04~0.06%, P0.3~0.45%, S≤0.08%, the mode of balance of Fe percentage by weights are matched somebody with somebody Material；
Second step：Preheating：Will optimize calculate steel scrap, foundry returns, the pig iron input intermediate frequency furnace in preheated；
3rd step：Melting：By the steel scrap in intermediate frequency furnace, foundry returns, the pig iron fusing after, put into its quantity for furnace charge 18~ 28%, composition carries out pre-deoxidation for the deoxidier of lime 70%+ fluorites 30%, then puts into ferromanganese, ferrosilicon and pure boron that baking is processed, When bonded hard ferrite magnet is warming up to 1400~1460 DEG C, add 0.1% deslagging agent once to remove the gred, be then covered by be sampled point of heat preserving agent etc. Analysis；
4th step：Both analysis：Iron liquid is taken quickly to be analyzed with stokehold spectrometer analysis combination carbon silicon heat analysis, according to Analysis result adjusts chemical composition；
5th step：Final deoxidizing：Bonded hard ferrite magnet is warming up to 1480~1640 DEG C, the aluminium that its quantity is iron liquid 0.1~0.3% is put into Carry out final deoxidizing；
6th step：Spheroidising and inoculation：Iron liquid flows to casting ladle from intermediate frequency furnace, carried out in casting ladle spheroidising, Inoculation and secondary except Slag treatment, adds 1.2~1.4% nodulizers that its quantity is iron liquid amount, the granularity of nodulizer for 8~ 26mm, nodulizer is FeSiMg8Re3；Add 1~1.2% inovulant that its quantity is iron liquid amount, the granularity of inovulant for 4~ 8mm, inovulant is 75 ferrosilicon；Add 0.1% deslagging agent that its quantity is iron liquid amount, cast triangle of being skimmed at once after spheroidizing reacion Test piece and spectrometer analysis detect that liquid iron balling and chemical composition are poured into a mould after qualified；
7th step：Cast：1480~1520 DEG C of pouring temperature, as cast its quantity of addition is iron liquid amount when casting ladle is poured into a mould 0.08~0.16% post inoculant, the granularity of inovulant is 2~6mm, and inovulant is 75 ferrosilicon, obtains being lived containing boron spheroidal cast iron Plug ring casting.
The beneficial effects of the invention are as follows：Smelting technology is simple, by the addition and ball that control carbon in cast iron, silicon and boron Change is processed, and casts out high-performance anti-attrition spheroidal graphite cast-iron, while reducing production cost, is particularly suitable for cast pistons ring.
Specific embodiment
Embodiment 1：
A kind of method for preparing cast-iron piston ring of this example, including following several steps：
The first step：Dispensing：By steel scrap, foundry returns, the pig iron, ferromanganese, ferrosilicon, pure boron press C2.9%, Si2.2%, Mn0.8%, B0.04%, P0.3%, S≤0.08%, the mode of balance of Fe percentage by weights carries out dispensing；
Second step：Preheating：Will optimize calculate steel scrap, foundry returns, the pig iron input intermediate frequency furnace in preheated；
3rd step：Melting：After by the steel scrap in intermediate frequency furnace, foundry returns, pig iron fusing, its quantity is put into for furnace charge 18%, into Being divided into the deoxidier of lime 70%+ fluorites 30% carries out pre-deoxidation, then puts into ferromanganese, ferrosilicon and pure boron that baking is processed, works as iron liquid Temperature is warming up to 1400 DEG C, adds 0.1% deslagging agent once to remove the gred, and is then covered by heat preserving agent and waits sampling analysis；
4th step：Both analysis：Iron liquid is taken quickly to be analyzed with stokehold spectrometer analysis combination carbon silicon heat analysis, according to Analysis result adjusts chemical composition；
5th step：Final deoxidizing：Bonded hard ferrite magnet is warming up to 1480 DEG C, putting into the aluminium that its quantity is iron liquid 0.1% carries out final deoxidizing；
6th step：Spheroidising and inoculation：Iron liquid flows to casting ladle from intermediate frequency furnace, carried out in casting ladle spheroidising, Inoculation and secondary except Slag treatment, adds 1.2% nodulizer that its quantity is iron liquid amount, and the granularity of nodulizer is 8mm, nodularization Agent is FeSiMg8Re3；1% inovulant that its quantity is iron liquid amount is added, the granularity of inovulant is 4mm, and inovulant is 75 ferrosilicon； 0.1% deslagging agent that its quantity is iron liquid amount is added, skimmed at once after spheroidizing reacion cast test wedge and spectrometer analysis detection Poured into a mould after liquid iron balling and chemical composition are qualified；
7th step：Cast：1480 DEG C of pouring temperature, as cast adds 0.08% 2 that its quantity is iron liquid amount when casting ladle is poured into a mould Secondary inovulant, the granularity of inovulant is 2mm, and inovulant is 75 ferrosilicon, obtains boracic ductile iron piston ring casting.
Embodiment 2：
A kind of method for preparing cast-iron piston ring of this example, including following several steps：
The first step：Dispensing：By steel scrap, foundry returns, the pig iron, ferromanganese, ferrosilicon, pure boron press C3.1%, Si2.3%, Mn0.95%, B0.05%, P0.375%, S≤0.08%, the mode of balance of Fe percentage by weights carries out dispensing；
Second step：Preheating：Will optimize calculate steel scrap, foundry returns, the pig iron input intermediate frequency furnace in preheated；
3rd step：Melting：After by the steel scrap in intermediate frequency furnace, foundry returns, pig iron fusing, its quantity is put into for furnace charge 23%, into Being divided into the deoxidier of lime 70%+ fluorites 30% carries out pre-deoxidation, then puts into ferromanganese, ferrosilicon and pure boron that baking is processed, works as iron liquid Temperature is warming up to 1430 DEG C, adds 0.1% deslagging agent once to remove the gred, and is then covered by heat preserving agent and waits sampling analysis；
4th step：Both analysis：Iron liquid is taken quickly to be analyzed with stokehold spectrometer analysis combination carbon silicon heat analysis, according to Analysis result adjusts chemical composition；
5th step：Final deoxidizing：Bonded hard ferrite magnet is warming up to 1510 DEG C, putting into the aluminium that its quantity is iron liquid 0.2% carries out final deoxidizing；
6th step：Spheroidising and inoculation：Iron liquid flows to casting ladle from intermediate frequency furnace, carried out in casting ladle spheroidising, Inoculation and secondary except Slag treatment, adds 1.3% nodulizer that its quantity is iron liquid amount, and the granularity of nodulizer is 17mm, nodularization Agent is FeSiMg8Re3；1.1% inovulant that its quantity is iron liquid amount is added, the granularity of inovulant is 6mm, and inovulant is 75 silicon Iron；0.1% deslagging agent that its quantity is iron liquid amount is added, skimmed at once after spheroidizing reacion cast test wedge and spectrometer analysis Poured into a mould after detection liquid iron balling and chemical composition are qualified；
7th step：Cast：1500 DEG C of pouring temperature, as cast adds 0.12% 2 that its quantity is iron liquid amount when casting ladle is poured into a mould Secondary inovulant, the granularity of inovulant is 4mm, and inovulant is 75 ferrosilicon, obtains boracic ductile iron piston ring casting.
Embodiment 3：
A kind of method for preparing cast-iron piston ring of this example, including following several steps：
The first step：Dispensing：By steel scrap, foundry returns, the pig iron, ferromanganese, ferrosilicon, pure boron by 3.3%, Si2.4%, Mn1.1%, B0.06%, P0.45%, S≤0.08%, the mode of balance of Fe percentage by weights carries out dispensing；
Second step：Preheating：Will optimize calculate steel scrap, foundry returns, the pig iron input intermediate frequency furnace in preheated；
3rd step：Melting：After by the steel scrap in intermediate frequency furnace, foundry returns, pig iron fusing, its quantity is put into for furnace charge 28%, into Being divided into the deoxidier of lime 70%+ fluorites 30% carries out pre-deoxidation, then puts into ferromanganese, ferrosilicon and pure boron that baking is processed, works as iron liquid Temperature is warming up to 1460 DEG C, adds 0.1% deslagging agent once to remove the gred, and is then covered by heat preserving agent and waits sampling analysis；
4th step：Both analysis：Iron liquid is taken quickly to be analyzed with stokehold spectrometer analysis combination carbon silicon heat analysis, according to Analysis result adjusts chemical composition；
5th step：Final deoxidizing：Bonded hard ferrite magnet is warming up to 1640 DEG C, putting into the aluminium that its quantity is iron liquid 0.3% carries out final deoxidizing；
6th step：Spheroidising and inoculation：Iron liquid flows to casting ladle from intermediate frequency furnace, carried out in casting ladle spheroidising, Inoculation and secondary except Slag treatment, adds 1.4% nodulizer that its quantity is iron liquid amount, and the granularity of nodulizer is 26mm, nodularization Agent is FeSiMg8Re3；1.2% inovulant that its quantity is iron liquid amount is added, the granularity of inovulant is 8mm, and inovulant is 75 silicon Iron；0.1% deslagging agent that its quantity is iron liquid amount is added, skimmed at once after spheroidizing reacion cast test wedge and spectrometer analysis Poured into a mould after detection liquid iron balling and chemical composition are qualified；
7th step：Cast：1520 DEG C of pouring temperature, as cast adds 0.16% 2 that its quantity is iron liquid amount when casting ladle is poured into a mould Secondary inovulant, the granularity of inovulant is 6mm, and inovulant is 75 ferrosilicon, obtains boracic ductile iron piston ring casting.
Specific embodiment of the invention is described above, but these explanations can not be considered as limiting the present invention Scope, protection scope of the present invention limits by appended claims, Wang where appointing on the basis of the claims in the present invention What modification, equivalent and improvement etc., each falls within the Inner of protection scope of the present invention.

Claims (2)

1. a kind of cast-iron piston ring, it is characterised in that：The percentage by weight of its composition is：C2.9~3.3%, Si2.2~ 2.4%th, Mn0.8~1.1%, B0.04~0.06%, P0.3~0.45%, S≤0.08%, balance of Fe.
2. a kind of method of the cast-iron piston ring prepared described in claim 1, it is characterised in that:Including following several steps：
The first step：Dispensing：By steel scrap, foundry returns, the pig iron, ferromanganese, ferrosilicon, pure boron press C2.9~3.3%, Si2.2~2.4%, Mn0.8~1.1%, B0.04~0.06%, P0.3~0.45%, S≤0.08%, the mode of balance of Fe percentage by weights are matched somebody with somebody Material；
Second step：Preheating：Will optimize calculate steel scrap, foundry returns, the pig iron input intermediate frequency furnace in preheated；
3rd step：Melting：By the steel scrap in intermediate frequency furnace, foundry returns, the pig iron fusing after, put into its quantity for furnace charge 18~ 28%, composition carries out pre-deoxidation for the deoxidier of lime 70%+ fluorites 30%, then puts into ferromanganese, ferrosilicon and pure boron that baking is processed, When bonded hard ferrite magnet is warming up to 1400~1460 DEG C, add 0.1% deslagging agent once to remove the gred, be then covered by be sampled point of heat preserving agent etc. Analysis；
4th step：Both analysis：Iron liquid is taken quickly to be analyzed with stokehold spectrometer analysis combination carbon silicon heat analysis, according to Analysis result adjusts chemical composition；
5th step：Final deoxidizing：Bonded hard ferrite magnet is warming up to 1480~1640 DEG C, the aluminium that its quantity is iron liquid 0.1~0.3% is put into Carry out final deoxidizing；
6th step：Spheroidising and inoculation：Iron liquid flows to casting ladle from intermediate frequency furnace, carried out in casting ladle spheroidising, Inoculation and secondary except Slag treatment, adds 1.2~1.4% nodulizers that its quantity is iron liquid amount, the granularity of nodulizer for 8~ 26mm, nodulizer is FeSiMg8Re3；Add 1~1.2% inovulant that its quantity is iron liquid amount, the granularity of inovulant for 4~ 8mm, inovulant is 75 ferrosilicon；Add 0.1% deslagging agent that its quantity is iron liquid amount, cast triangle of being skimmed at once after spheroidizing reacion Test piece and spectrometer analysis detect that liquid iron balling and chemical composition are poured into a mould after qualified；
7th step：Cast：1480~1520 DEG C of pouring temperature, as cast its quantity of addition is iron liquid amount when casting ladle is poured into a mould 0.08~0.16% post inoculant, the granularity of inovulant is 2~6mm, and inovulant is 75 ferrosilicon, obtains being lived containing boron spheroidal cast iron Plug ring casting.
CN201611165025.2A 2016-12-16 2016-12-16 Cast iron piston ring and preparation method thereof Pending CN106702257A (en)

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Application Number Priority Date Filing Date Title
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1045424A (en) * 1989-04-28 1990-09-19 山东省新材料研究所 A kind of antifriction cast iron and production method thereof
CN101161845A (en) * 2007-11-28 2008-04-16 中国船舶重工集团公司第十二研究所 Synthetic cast iron for production of hydraulic piece and preparation method thereof
CN101773989A (en) * 2010-01-29 2010-07-14 迁安市津唐球墨铸管有限公司 Process for producing ductile cast iron by short-flow melting and sodium silicate sand molding

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1045424A (en) * 1989-04-28 1990-09-19 山东省新材料研究所 A kind of antifriction cast iron and production method thereof
CN101161845A (en) * 2007-11-28 2008-04-16 中国船舶重工集团公司第十二研究所 Synthetic cast iron for production of hydraulic piece and preparation method thereof
CN101773989A (en) * 2010-01-29 2010-07-14 迁安市津唐球墨铸管有限公司 Process for producing ductile cast iron by short-flow melting and sodium silicate sand molding

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
陆文华: "《铸铁及其熔炼》", 30 April 1981, 机械工业出版社 *

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Application publication date: 20170524