CN108570623A - A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method - Google Patents

A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method Download PDF

Info

Publication number
CN108570623A
CN108570623A CN201810589816.0A CN201810589816A CN108570623A CN 108570623 A CN108570623 A CN 108570623A CN 201810589816 A CN201810589816 A CN 201810589816A CN 108570623 A CN108570623 A CN 108570623A
Authority
CN
China
Prior art keywords
alloy
powder
sro
casting
iron
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.)
Withdrawn
Application number
CN201810589816.0A
Other languages
Chinese (zh)
Inventor
罗丰华
赵忠新
夏光明
贺立
卢静
李益民
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.)
Central South University
Original Assignee
Central South 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 Central South University filed Critical Central South University
Priority to CN201810589816.0A priority Critical patent/CN108570623A/en
Publication of CN108570623A publication Critical patent/CN108570623A/en
Priority to CN201910407525.XA priority patent/CN109972057A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/002—Heat treatment of ferrous alloys containing Cr
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • C22C33/06—Making ferrous alloys by melting using master alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/32—Ferrous alloys, e.g. steel alloys containing chromium with boron

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method, and the content of alloy each element is Cr：9.0~13.0, B：2.6~2.9, C：0.7~0.9, Nb：0.4~0.8, V：The content of 0.4~0.8, Mn are less than 0.3, Sr：0.02~0.6, surplus Fe, C, B total amount is 3.3~3.6；C/Cr content ratios：0.06~0.08；The total amount of Nb, V are 0.5~1.0, the preparation of Fe SrO powder compacts are got out first, by cast alloys after alloying ingredient, melting and Metamorphism treatment.Ingot casting average hardness of the present invention HRC66.5~69.6, impact flexibility reach 12.5~16.3J/cm2, bending strength reaches 1260~1662MPa.

Description

A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method
Technical field
The invention belongs to high-hardness and wear-resistant cast-iron fields, are related to a kind of fine hard phase and super saturated solid solution that strontium is rotten Body, martensitic matrix phase wear and corrosion resistant cast iron alloy and its component preparation method, can be widely used for electric power, metallurgy, machinery, Mechanical wearing piece manufacture in the industries such as chemical industry.
Technical background
Fe-Cr-B-C abrasion resistant casting alloys are mainly with Fe2B or M2B is hard phase, has good toughness and high rigidity, height Corrosion resistance, melting-casting manufacturability is good, has very foreground.
Metamorphism treatment is to improve one of Fe-Cr-B-C alloy structures and mechanical property effective ways.Alterant is according to effect The elements such as strong carbon, nitrogen, sulfide formation element, such as Ti, V, and strong constitutional supercooling element, such as surface active element can be divided into Rare earth (RE), Mg etc..
Rare earth element is gathered on the solid growth interface of liquid, and limitation crystal grain is grown up, to improve the hardness of alloy, intensity and resistance to Mill property；And thinning microstructure, so that boride suspension shape and graininess distribution is occurred, improves impact flexibility.Research shows that：In Fe-Cr- The cerium (Ce) of addition 0.6% can make impact flexibility improve 86.4% in B-C alloys.Add the mixing alterant of 1.0% (Ce+La) Into Fe-Cr-B alloys, the hardness of alloy increases to 70.2HRC by 52HRC, and impact flexibility is by 3.36J/cm2It is increased to 6.38J/cm2。
RE Modified can rare earth alloy or rare-earth wires single Modification Manners, can also take compound modification treatment, i.e., with N, The mixture of the elements such as Ti, V, Mg, Si and rare earth is as alterant.Silicon Mg mixed rare-earth rotten (RE-Si-Mg) is most common Composite inoculating, some researches show that：Fe-Cr-B-C alloys impact toughness after RE-Si-Mg is rotten is higher than not rotten premise 72.2%；After RE-Ti goes bad and is heat-treated, impact flexibility improves 1.8 times；Through RE-Mg go bad impact flexibility improve 34.6%；Desmachyme all disappears after RE-Ti-N is rotten, and toughness improves 133.3%；Through RE-Mg-V-Ti Metamorphism treatments Afterwards, impact flexibility reaches 15.6J/cm2；After RE-Ti-Si-V Metamorphism treatments, impact flexibility reaches 12J/cm2More than.
These using the method for RE Modified all there are one common difficulty, i.e. the pure rare earth, rare earth alloy of high activity or multiple Close rare earth material.Due to the high activity of rare earth so that the tissue of alloy, performance are difficult to control after alterant itself or Metamorphism treatment System, modification effect are difficult to ensure.
Document 1：LM cathodes research-emission principle and present Research [D] Beijing University of Technology, 2001：pp44-50.Carbonization La2O3The chemical balance of-Mo alloys：
3Mo2C(s)+La2O3(s)=2La (s, l)+3CO (g)+6Mo
Due to Mo2The effect of C, the reduction reaction free enthalpy variation for generating simple substance La is small very much, to reaction product La With the also high 10 several orders of magnitude of the equilibrium partial pressure of CO.When temperature is higher than 1673K, i.e., 1400 DEG C, CO partial pressures are less than E-9atm When, reaction equation can carry out to the right automatically, i.e. reduction generates simple substance La.
Patent document 2：The antifriction alloy hardness of Authorization Notice No. CN 105695884B, preparation are HRC66~70, impact 4~9J/cm of toughness2.The hardness of such alloy is higher, but impact flexibility is insufficient, and intensity index is relatively low, and bending strength is relatively low, 346~477MPa ranges limit the occasion that the Alloyapplication is big in some external loads, impact resistance is needed to act on.
Invention content
The object of the present invention is to provide a kind of rotten toughening high hardness alloy of rare earth strontium and its casting methods.This method uses It is alterant to have SrO, and the carbide, boride in high temperature melting state Fe-Cr-B-C alloys, which have, promotes high activity Sr first The thermodynamic condition that element is formed, and form compound containing Sr in C, B so that casting alloy structure refinement, carbon boride break Netted and presentation graininess distribution, to improve impact flexibility.
Since SrO powder densities are very low, being added directly into melt can float with clinker and cause Sr loss of elements, to lose Remove modification effect, thus the present invention using SrO powder with iron powder after mixing, be molded into powder compact, then with Fe-Cr-B-C Casting alloy melts together.The weight ratio of SrO powder and iron powder substantially 1:3~19, that is, form Fe-4.27~21.36wt.%Sr Mixing briquetting.The too high levels of the too low then Fe of Sr amounts, can influence burdening calculation；And then green compact forming is tired for Sr too high levels It is difficult.Wherein SrO powder is white amorphous powder, and SrO contents are more than 99.0%, therefore do not do to its purity and granularity and strictly want It asks.Fe powder is to restore Fe powder or water atomization Fe powder, can be containing in the alloying element or impurity ranges in modified cast iron in Fe powder Element, such as Ni, V, Cr, being subject to does not influence briquette forming and influences burdening calculation.
The high-wearing feature for the patent document 2 that the present invention selects, high corrosion-resistant Fe-Cr-B-C alloys are basic alloy, then are added Add 0.02~0.6%Sr elements rotten.The multi-element eutectic alloy containing elements such as Fe, Cr, B, C, Nb, V, Sr is formed, each element Mass percentage is Cr：9.0~13.0, B：2.6~2.9, C：0.7~0.9, Nb：0.4~0.8, V：0.4~0.8, Mn's Content is less than 0.3, Sr：0.02~0.6, S, P：≤ 0.01, surplus Fe.Wherein C, B summation：3.3~3.6；C/Cr content ratios： 0.06~0.08；The summation of Nb, V are 0.5~1.0.
With reference to patent document 2, it is specific prepare alloy when, can be used ferrochrome (high-carbon, middle carbon, micro- carbon), ferro-boron, ferro-niobium, Vanadium iron, pure iron, etc. according to component requirements dispensing.Raw material and its composition are listed in table 1.
Table 1 can be applied to prepare the raw material and composition of invention alloy
The material composition of table 1 is not unique, and specific ingredient raw material obtained by reality determine.Wherein ferrochrome, Crome metal, ferro-boron, ferro-niobium and vanadium iron provide the content of Cr, B, Nb and V of invention alloy, and high carbon ferro-chrome is used for balancing C content.It is pure Iron can be electrical pure iron, electromagnetic pure iron or ingot iron.
The method specifically comprises the following steps：
(1) Fe-SrO powder compacts prepare
After mixing using iron powder and SrO powder, it is molded into powder compact.The weight ratio of SrO powder and iron powder substantially 1:3 ~19, that is, form the Fe-SrO mixing briquettings of Fe-4.27~21.36%Sr.The carrier to go bad as rare earth Sr.
(2) alloying ingredient, melting and Metamorphism treatment
After weighing good corresponding raw material according to the component requirements proportioning of Fe-Cr-B-C alloys, then add 0.02~0.6%Sr Element is rotten.Fe-SrO powder compacts are positioned over furnace bottom first, be then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and Pure iron.Induction furnace, vaccum sensitive stove etc. can be used carry out melting and prepares alloy.Fusion temperature is higher than 1560~1660 DEG C；Then it drops Low furnace power, after melt temperature is down to 1300~1380 DEG C, with the fine aluminium deoxidation of dispensing total amount 0.1~0.15%；Continue Heat preservation stands about 5~10 minutes.
(3) it casts
Ranging from 1250~1300 DEG C of cast temperature.Designed alloy has deep eutectic ingredient, is molded in normal sands Non-equilibrium matrix can be formed under the conditions of making, such as amorphous, nanocrystalline or martensitic structure.Since designed alloy is total Brilliant ingredient, melt have good mobility fine, can casting and forming by various methods, such as normal sands Mold casting or The special casting method such as model casting, lost foam casting, permanent mold casting, ceramic mold casting, die casting, centrifugal casting.From solidification Temperature should be not less than 60 DEG C/min to the cooling velocity between 600 DEG C, but volume can be caused to become since non-equilibrium transformation occurs Change, lead to stress cracking phenomenon since temperature is inconsistent when preparing heavy castings, casting should be between 600~800 DEG C Release the constraint of mold.Stress relief annealing technique and necessary machining processes less than 600 DEG C subsequently can be used in ingot casting.
Step (1) described iron powder is purity >=98.5%, the reduced iron powder or purity >=99.0% of -100 mesh of granularity, grain Spend the water-atomized iron powder of -100 mesh, or quite granularity contains a small amount of alloy iron powder for not influencing casting alloy ingredient.Also may be used To select the powder of smaller particle size, the compact strength with follow-up dispensing and furnace charge preparation is not influenced can be pressed by being subject to.
Step (1) is described to be uniformly mixed into mixed cartridge type batch mixing, V-type batch mixing or stir mixing, substantial uniform to realize .
Step (1) described green compact is die forming, and pressing pressure is 100~600MPa, and green compact size is unlimited.It can also adopt Take isostatic cool pressing method.
The purpose that Fe-SrO powder compacts are positioned over furnace bottom is by step (2)：The substances such as ferrochrome, ferro-boron have than pure iron Low fusion temperature, therefore can preferentially melt and be impregnated into the Fe-SrO powder compacts of bottom so that straight iron powder gradually melts, and Release SrO powder particles.Since the density of SrO is relatively low, about 4.7g/cm3, understand gradually upper emersion melt.It floats in SrO powder Process, by Fe3C、Cr3C2Equal carbide restore to form active Sr elements, and are reacted with C, B, are formed and are similar to Sr (B, C)6's Compound.By the metamorphism of Sr, the reticular structure and Needle-shaped boride of distribution along crystal boundary disappear, alloy by primary crystal matrix phase and Eutectic structure forms, and this eutectic structure, which is interted by tiny matrix phase with hard phase, to be formed so that the intensity of alloy and impact Toughness is improved.
The CO gases formed in SrO powder floating, reaction process also have the effect of degasification, slagging-off, to which further purification is molten Body.
If SrO powder is not previously prepared to be positioned over furnace bottom at briquetting, it is easy to float to bath surface, bath surface rapidly Oxygen content is high, and SrO is not easy to be reduced to form active Sr, and loses modification effect.
The Fe3C、Cr3C2Equal carbide are formed by C and Fe element reactions when high carbon ferro-chrome and fusing, due to Fe3C、 Cr3C2The stability of equal carbide at high temperature is not so good as Mo2C, and the temperature melted is more than 1400 DEG C of reactions described in document 1 Temperature, the partial pressure of CO gases is also extremely low in melt；And the property of Sr and La is much like, thus it is similar to document 1, it generates and lives The reduction reaction of property Sr can carry out.EDS energy spectrum analysis, which also indicates that, contains Sr elements in casting alloy object phase.
Casting described in step (3) also can realize casting by placing the means such as chill in water cooling, swage, mold, with into One step promotes matrix that non-equilibrium transformation occurs, and forms high hardness martensitic.
The Fe-Cr-B-C alloys that the Sr Modification Manners of the present invention are not limited to, can also be applied to other cast irons and C content are higher Smelting iron and steel is rotten, micronization processes.
The present invention's is mainly characterized by directly using SrO powder mixed with iron powder, forms powder compact, is carried as Sr elements are rotten Body.Utilize Fe in Fe-Cr-B-C alloy high-temp melts3C、Cr3C2The reduction of equal carbide forms active Sr elements, and with C, B reacts, and is formed and is similar to Sr (B, C)6Compound, avoid the occurrence of that boride is netted and acicular texture, promote tiny eutectic It organizes the formation of, plays the rotten toughening effect of thinning microstructure.The matrix of ingot structure is mutually that Cr, B, C with high rigidity strengthen Non-equilibrium microstructure；Hard phase is boron, the carbon compound of high rigidity, and tiny eutectic structure is mutually formed with matrix.Ingot casting is whole Hardness reaches HRC66.5~69.6, and impact flexibility reaches 12.5~16.3J/cm2, bending strength reaches 1260~1662MPa.
Description of the drawings
6 cast sturcture of Fig. 1 present examples schemes；
6 casting alloy X-ray diffracting spectrum of Fig. 2 present examples；
The EDS collection of illustrative plates and ingredient of 6 casting matrix phase of Fig. 3 present examples.
Specific implementation mode
The various method of smelting of the present invention, casting method are not limited by following examples, and any right in the present invention is wanted The improvement in range and variation for asking book claimed are all within protection scope of the present invention.
Select high carbon ferro-chrome, chromic carbide iron, crome metal, ferro-boron, ferro-niobium, vanadium iron, ingot iron, straight iron powder, SrO powder, pure Aluminium etc. is raw material, and alloy is configured in the composition range that invention requires.
Embodiment 1. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:3, that is, form the Fe-SrO mixing briquettings of Fe-21.36wt.%Sr.The carrier to go bad as rare earth Sr.
It is original to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, vanadium iron, ingot iron and above-mentioned Fe-SrO mixing briquetting Material, composition range are as follows：Cr:10.0wt.%；B:2.9wt.%；C:0.7wt.%；Nb:0.4wt.%；V:0.2wt.%；Sr: 0.6wt.%；Impurity element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore not It is listed in Table 2.
After weighing good corresponding raw material according to component requirements proportioning, using induction melting and sand mold die cast.Specific steps For：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1660 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1380 DEG C, with dispensing total amount 0.15% fine aluminium deoxidation；Continue heat preservation and stands about 10 minutes.
Ranging from 1300 DEG C of cast temperature.About 6 minutes after having cast, sand mould is opened, ingot casting temperature is less than 800 at this time DEG C, from setting temperature to 800 DEG C cooling rate be about 70 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC68.2, and impact flexibility reaches 12.6J/cm2, bending strength reaches 1380MPa。
Embodiment 2. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:19, that is, form the Fe-SrO mixing briquettings of Fe-4.27wt.%Sr.The carrier to go bad as rare earth Sr.
It is raw material, ingredient to select high carbon ferro-chrome, crome metal, ferro-boron, ferro-niobium, ingot iron and above-mentioned Fe-SrO mixing briquetting Range is as follows：Cr:10.0wt.%；B:2.7wt.%；C:0.7wt.%；Nb:0.5wt.%；Sr:0.02wt.%；Impurity element Control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore unlisted in table 2.
After weighing good corresponding raw material according to component requirements proportioning, vacuum induction melting and the casting of water cooling swage can be used It makes.The specific steps are：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium and pure iron.Fusing temperature Degree is 1560 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1300 DEG C, with dispensing total amount 0.1% Fine aluminium deoxidation；Continue heat preservation and stands about 5 minutes.
Ranging from 1250 DEG C of cast temperature.About 10 minutes after having cast, water cooling swage is opened, ingot casting temperature is less than at this time 600 DEG C, from setting temperature to 600 DEG C cooling rate be about 70 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC69.6, and impact flexibility reaches 13.4J/cm2, bending strength reaches 1260MPa。
Embodiment 3. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:10, that is, form the Fe-SrO mixing briquettings of Fe-7.77wt.%Sr.The carrier to go bad as rare earth Sr.
It is raw material to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, ingot iron and above-mentioned Fe-SrO mixing briquetting, at Divide range as follows：Cr：10.0wt.%；B：2.7wt.%；C:0.8wt.%；Nb:0.6wt.%；Sr:0.10wt.%；Impurity member Element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore unlisted in table 2.
After good corresponding raw material being weighed according to component requirements proportioning, using induction melting and model casting, the specific steps are：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1580 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1320 DEG C, with dispensing total amount 0.12% fine aluminium deoxidation；Continue heat preservation and stands about 8 minutes.
Ranging from 1280 DEG C of cast temperature.About 10 minutes after having cast, sand mold fusible pattern is opened, ingot casting temperature is less than at this time 700 DEG C, from setting temperature to 700 DEG C cooling rate be about 60 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC67.6, and impact flexibility reaches 16.3J/cm2, bending strength reaches 1460MPa。
Embodiment 4. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:15, that is, form the Fe-SrO mixing briquettings of Fe-5.34wt.%Sr.The carrier to go bad as rare earth Sr.
It is original to select high carbon ferro-chrome, crome metal, ferro-boron, ferro-niobium, vanadium iron, ingot iron and above-mentioned Fe-SrO mixing briquetting Material, composition range are as follows：Cr：11.0wt.%；B：2.7wt.%；C:0.7wt.%；Nb:0.2wt.%；V:0.4wt.%；Sr: 0.20wt.%；Impurity element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore It is unlisted in table 2.
After good corresponding raw material being weighed according to component requirements proportioning, using induction melting and sand casting, the specific steps are：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1600 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1350 DEG C, with dispensing total amount 0.13% fine aluminium deoxidation；Continue heat preservation and stands about 9 minutes.
Ranging from 1280 DEG C of cast temperature.About 7 minutes after having cast, sand mould is opened, ingot casting temperature is less than 800 at this time DEG C, from setting temperature to 800 DEG C cooling rate be about 60 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC66.8, and impact flexibility reaches 12.5J/cm2, bending strength reaches 1520MPa。
Embodiment 5. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:4, that is, form the Fe-SrO mixing briquettings of Fe-17.09wt.%Sr.The carrier to go bad as rare earth Sr.
It is original to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, vanadium iron, ingot iron and above-mentioned Fe-SrO mixing briquetting Material, composition range are as follows：Cr：10.0wt.%；B：2.6wt.%；C：0.6wt.%；Nb：0.3wt.%；V：0.1wt.%；Sr: 0.30wt.%；Impurity element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore It is unlisted in table 2.
After weighing good corresponding raw material according to component requirements proportioning, using induction melting and lost foam casting, specific steps It is as follows：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1650 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1325 DEG C, with dispensing total amount 0.12% fine aluminium deoxidation；Continue heat preservation and stands about 6 minutes.
Ranging from 1285 DEG C of cast temperature.About 8 minutes after having cast, disappearance model sand mold is opened, ingot casting temperature is less than at this time 700 DEG C, from setting temperature to 700 DEG C cooling rate be about 70 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC69.5, and impact flexibility reaches 14.7J/cm2, bending strength reaches 1360MPa。
Embodiment 6. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:18, that is, form the Fe-SrO mixing briquettings of Fe-4.50wt.%Sr.The carrier to go bad as rare earth Sr.
It is raw material to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, ingot iron and above-mentioned Fe-SrO mixing briquetting, at Divide range as follows：Cr：10.0wt.%；B：2.6wt.%；C：0.8wt.%；Nb：0.8wt.%；Sr:0.40wt.%；Impurity member Element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore unlisted in table 2.
It is specific to walk using vacuum induction melting and iron mould casting after weighing good corresponding raw material according to component requirements proportioning It is rapid as follows：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1590 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1315 DEG C, with dispensing total amount 0.14% fine aluminium deoxidation；Continue heat preservation and stands about 7 minutes.
Ranging from 1290 DEG C of cast temperature.About 10 minutes after having cast, swage is opened, ingot casting temperature is less than 600 DEG C at this time, Cooling rate from setting temperature to 600 DEG C is about 70 DEG C/min.It is air-cooled to room temperature.
Fig. 1 is casting alloy tissue, and based on Fe primary phases and eutectic phase, wherein eutectic phase is Fe phases and boron, carbon compound The eutectic structure of object；Fig. 2 is the X-ray diffracting spectrum of casting alloy, and display alloy substrate is α-Fe phases, and diffraction maximum is wider, And it is wider near 65o, therefore be the martensitic phase for having a large amount of Cr solid solutions, carbon, boron compound Fe2B、Fe3C and Cr23C6For base The complex chemical compound of plinth, and show Sr (B, C)6Compound exists；Fig. 3 is casting alloy matrix phase EDS collection of illustrative plates and analysis As a result, as a result EDS can only show in alloy there are Sr elements in the qualitative analysis of ingredient, illustrate that SrO produces work with melt With, make Sr elements occur alloying, play melt metamorphism.
Gained ingot casting integral hardness reaches HRC66.5, and impact flexibility reaches 15.6J/cm2, bending strength reaches 1546MPa。
Embodiment 7. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:8, that is, form the Fe-SrO mixing briquettings of Fe-9.49wt.%Sr.The carrier to go bad as rare earth Sr.
It is original to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, vanadium iron, ingot iron and above-mentioned Fe-SrO mixing briquetting Material, composition range are as follows：Cr：11.0wt.%；B：2.6wt.%；C：0.9wt.%；Nb：0.2wt.%；V：0.2wt.%；Sr: 0.50wt.%；Impurity element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore It is unlisted in table 2.
After weighing good corresponding raw material according to component requirements proportioning, induction melting and lost foam casting can be used.Specific step It is rapid as follows：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1620 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1350 DEG C, with dispensing total amount 0.13% fine aluminium deoxidation；Continue heat preservation and stands about 8 minutes.
Ranging from 1260 DEG C of cast temperature.About 9 minutes after having cast, disappearance model sand mold is opened, ingot casting temperature is less than at this time 600 DEG C, from setting temperature to 600 DEG C cooling rate be about 70 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC68.4, and impact flexibility reaches 13.2J/cm2, bending strength reaches 1662MPa。
Embodiment 8. uses iron powder after mixing, to be molded into powder compact with SrO powder.The weight ratio of SrO powder and iron powder Substantially 1:12, that is, form the Fe-SrO mixing briquettings of Fe-6.57wt.%Sr.The carrier to go bad as rare earth Sr.
It is original to select high carbon ferro-chrome, chromic carbide iron, ferro-boron, ferro-niobium, vanadium iron, ingot iron and above-mentioned Fe-SrO mixing briquetting Material, composition range are as follows：Cr：13.0wt.%；B：2.6wt.%；C：0.8wt.%；Nb：0.6wt.%；V：0.4wt.%；Sr: 0.06wt.%；Impurity element control is shown in Table 2.The impurity such as a small amount of Al, Mn, N will not cause alloy property essence to change, therefore It is unlisted in table 2.
After weighing good corresponding raw material according to component requirements proportioning, using induction melting and lost foam casting, specific steps It is as follows：
Fe-SrO powder compacts are positioned over furnace bottom, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron. Fusion temperature is 1600 DEG C；Until completely melted, furnace power is reduced, after melt temperature is down to 1320 DEG C, with dispensing total amount 0.12% fine aluminium deoxidation；Continue heat preservation and stands about 6 minutes.
Ranging from 1280 DEG C of cast temperature.About 9 minutes after having cast, disappearance model sand mold is opened, ingot casting temperature is less than at this time 700 DEG C, from setting temperature to 700 DEG C cooling rate be about 60 DEG C/min.It is air-cooled to room temperature.
Gained ingot casting integral hardness reaches HRC69.0, and impact flexibility reaches 16.0J/cm2, bending strength reaches 1432MPa。
Casting alloy performance detection prepared by each embodiment is as described below：
1. pair example casting metal carries out hardness test using HR-150A Rockwell hardness machines, load 150Kg makes a call to five It is averaged after point, is listed in table 2.
2. pair example casting metal carries out impact flexibility test using JBS-300B shock machines, range 150J is beaten It is averaged after five samples, is listed in table 2.
3. pair example casting metal material electronics universal testing machine carries out three-point bending resistance experiment, sample size is 2 × 5 × The rectangular specimen of 50mm, span 30mm take the bending strength average value of three same treatment samples to be listed in table 2.
The ingredient of 2 embodiment of table and hardness, impact flexibility and bending strength

Claims (5)

  1. The toughening high hardness alloy 1. a kind of rare earth strontium goes bad, it is characterised in that：The mass percentage of alloy each element is Cr： 9.0~13.0, B：2.6~2.9, C：0.7~0.9, Nb：0.4~0.8, V：The content of 0.4~0.8, Mn are less than 0.3, Sr： 0.02~0.6, S, P：≤ 0.01, surplus Fe, wherein C, B total mass percentage is：3.3~3.6；C/Cr mass ratioes： 0.06~0.08；The gross mass percentage composition of Nb, V is：0.5~1.0.
  2. The casting method of toughening high hardness alloy 2. rare earth strontium as described in claim 1 goes bad, it is characterised in that including following Process：
    (1) Fe-SrO powder compacts prepare
    After mixing using iron powder and SrO powder, it is molded into powder compact, the weight ratio of SrO powder and iron powder is 1:3~19, shape At the Fe-SrO mixing briquettings of Fe-4.27~21.36%Sr, the carrier to go bad as rare earth Sr；
    (2) alloying ingredient, melting and Metamorphism treatment
    After weighing good corresponding raw material according to the component requirements proportioning of Fe-Cr-B-C alloys, then add 0.02~0.6%Sr elements It is rotten：Fe-SrO powder compacts are positioned over furnace bottom first, are then placed in ferrochrome, crome metal, ferro-boron, ferro-niobium, vanadium iron and pure iron, Alloy is prepared using induction furnace melting, fusion temperature is 1560~1660 DEG C；Then furnace power is reduced, melt temperature is down to 1300~1380 DEG C, with the fine aluminium deoxidation of dispensing total amount 0.1~0.15%；Continue heat preservation and stands 5~10 minutes；
    (3) it casts
    Ranging from 1250~1300 DEG C of cast temperature, designed alloy has deep eutectic ingredient, in common sand casting item Non-equilibrium matrix can be formed under part, by various methods casting and forming, from setting temperature to 600 DEG C cooling speed Degree should be not less than 60 DEG C/min.
  3. The casting method of toughening high hardness alloy 3. rare earth strontium as claimed in claim 2 goes bad, it is characterised in that：It prepares large-scale When casting, casting releases the constraint of mold at 600~800 DEG C again.
  4. The casting method of toughening high hardness alloy 4. rare earth strontium as claimed in claim 2 goes bad, it is characterised in that：Step (1) The iron powder is purity >=98.5%, the reduced iron powder or purity >=99.0% of -100 mesh of granularity, the water mist of -100 mesh of granularity Change the alloy iron powder of iron powder or -100 mesh of granularity.
  5. The casting method of toughening high hardness alloy 5. rare earth strontium as claimed in claim 2 goes bad, it is characterised in that：Step (1) The green compact is die forming, and pressing pressure is 100~600MPa, or takes isostatic cool pressing method.
CN201810589816.0A 2018-06-08 2018-06-08 A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method Withdrawn CN108570623A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201810589816.0A CN108570623A (en) 2018-06-08 2018-06-08 A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method
CN201910407525.XA CN109972057A (en) 2018-06-08 2019-05-15 A kind of strontium element toughening high hardness alloy and its casting method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810589816.0A CN108570623A (en) 2018-06-08 2018-06-08 A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method

Publications (1)

Publication Number Publication Date
CN108570623A true CN108570623A (en) 2018-09-25

Family

ID=63573226

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810589816.0A Withdrawn CN108570623A (en) 2018-06-08 2018-06-08 A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method

Country Status (1)

Country Link
CN (1) CN108570623A (en)

Similar Documents

Publication Publication Date Title
CN108660392A (en) A kind of Si strengthens high hardness wear-resisting alloy and its casting method
CN108570623A (en) A kind of rare earth strontium goes bad toughening high hardness alloy and its casting method
CN108425072A (en) A kind of Rare Earth Lanthanum toughening high hard alloy and its casting and heat treatment method
CN108396249A (en) A kind of lanthanum carbonate toughening high hard alloy and its casting and heat treatment method
CN108707835A (en) A kind of rare-earth yttrium toughening high hard alloy and its casting and heat treatment method
CN108570612A (en) A kind of Rare Earth Lanthanum goes bad toughening high hardness alloy and its casting method
CN108570624A (en) A kind of cerium goes bad toughening high hardness alloy and its casting method
CN108570609A (en) A kind of yttrium nitrate goes bad toughening high hardness alloy and its casting method
CN108660391A (en) A kind of strontium nitrate goes bad toughening high hardness alloy and its casting method
CN108677104A (en) A kind of rare earth bait goes bad toughening high hardness alloy and its casting method
CN108441776A (en) A kind of erbium nitrate goes bad toughening high hardness alloy and its casting method
CN108707836A (en) A kind of yttrium carbonate goes bad toughening high hardness alloy and its casting method
CN108707837A (en) A kind of rare-earth yttrium goes bad toughening high hardness alloy and its casting method
CN108411218A (en) A kind of strontium carbonate goes bad toughening high hardness alloy and its casting method
CN108707838A (en) A kind of lanthanum nitrate goes bad toughening high hardness alloy and its casting method
CN109972057A (en) A kind of strontium element toughening high hardness alloy and its casting method
CN108570622A (en) A kind of carbonic acid erbium goes bad toughening high hardness alloy and its casting method
CN108570611A (en) A kind of cerous nitrate goes bad toughening high hardness alloy and its casting method
CN108570610A (en) A kind of cerous carbonate goes bad toughening high hardness alloy and its casting method
CN108677105A (en) A kind of lanthanum carbonate goes bad toughening high hardness alloy and its casting method
CN109972051B (en) Yttrium modified high-hardness alloy and casting method thereof
CN110016624A (en) A kind of lanthanum goes bad high hardness alloy and its casting method
CN110004378A (en) A kind of bait goes bad toughening high hardness alloy and its casting method
CN108570608A (en) A kind of rare earth strontium toughening high hard alloy and its casting and heat treatment method
CN109972056A (en) A kind of cerium modified wear-resistant alloy and its casting method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WW01 Invention patent application withdrawn after publication
WW01 Invention patent application withdrawn after publication

Application publication date: 20180925