CN101348878A - Isothermal quench bainitic ductile cast iron and use thereof - Google Patents
Isothermal quench bainitic ductile cast iron and use thereof Download PDFInfo
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- CN101348878A CN101348878A CNA2008101962662A CN200810196266A CN101348878A CN 101348878 A CN101348878 A CN 101348878A CN A2008101962662 A CNA2008101962662 A CN A2008101962662A CN 200810196266 A CN200810196266 A CN 200810196266A CN 101348878 A CN101348878 A CN 101348878A
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Abstract
The invention relates to an austempering bainite spheroidal graphite cast iron and application thereof. The compositions by weight percent of the austempering bainite spheroidal graphite cast iron are 3.50 to 3.8 percent of carbon, 2.2 to 2.7 percent of silicon, 0.2 to 0.5 percent of manganese, less than or equal to 0.07 percent of phosphor, less than or equal to 0.03 percent of sulfur, 0.03 to 0.06 percent of magnesium, 0.01 to 0.04 percent of rhenium, 0.45 to 0.75 percent of copper, and the balance being iron. The austempering bainite spheroidal graphite cast iron is used as a fitting part of a pump or a fitting part of a pulling machine. The austempering bainite spheroidal graphite cast iron has the advantages that: firstly, the austempering bainite spheroidal graphite cast iron has superior comprehensive performance, is easy to manufacture and has low cost; secondly, the austempering bainite spheroidal graphite cast iron has long service life, low manufacturing cost, superior corrosion resistance and abrasion resistance, and good strength, plasticity and toughness; and thirdly, the industrial production of the austempering bainite spheroidal graphite cast iron on pump products, particularly the application of the austempering bainite spheroidal graphite cast iron on marine pump products and mine pump products and the application of the austempering bainite spheroidal graphite cast iron as the fitting part of the pulling machine effectively improve the product performance in the two industries and can bring about significant economic benefit.
Description
Technical field
The present invention relates to the bainite ductile iron field, especially relate to isothermal quench bainitic ductile cast iron and application thereof, this isothermal quench bainitic ductile cast iron is specially adapted to pump class accessory and drawing wire machine accessory.
Background technology
Isothermal quench bainitic ductile cast iron (Austempered Ductile Iron is called for short ADI) is the new metallic material with excellent comprehensive performance, it has high strength and high-plasticity concurrently, and have high-wearing feature, shock-resistance and a characteristic such as erosion resistance preferably, with its be applied in proper domain can effectively prolong product work-ing life, reduce cost.In twentieth century the 1970s and 1980s, comprise that in the world a few countries of Finland, China is researched and developed this.Along with further investigation and application, this material causes the great interest of brainstrust and greatly concern in field of engineering technology, is called as one of significant achievement of the metallurgical aspect of cast iron over nearly 40 years.The nineties has progressively obtained promotion and application widely in Japan, the U.S., Europe later, and relevant national standard has been implemented in issue in succession.Different according to the control of matrix and chemical ingredients, isothermal quench bainitic ductile cast iron has different performances, and the cost and the difficulty of making also can be different.
Good, with low cost for obtained performance and be easy to make bainite ductile iron, people have carried out long-term exploration, have proposed various improvement projects.For example, Chinese patent literature discloses a kind of bainite auctile iron isothermal quenching technology [application number: 200510044091.X], it has solved and has adopted the unfavorable processing of salt bath in the present isothermal quench bainitic ductile cast iron technology, also can pollute, add the problem that behind the alloying element cost is increased, adopt the complete processing of water, have pollution-free as medium, products obtained therefrom tissue, performance can be controlled advantages such as reliable in quality.Its technology is: a. is heated to the austenitic area insulation with spheroidal graphite cast iron; B. in water, cool off; C. putting into constant-temperature oven cools off; D. the workpiece that isothermal is good is come out of the stove to cool off and is got final product.The somebody has invented a kind of bainite ductile iron abrading-ball and production technique [application number: 200610048751.6] thereof, and the weight ratio of constituents of this ductile iron grinding ball (wt.%) is: C:3.4～3.8%; Si:2.8～3.3%; Mn:2.9～3.4%; Mg:0.03～0.05%; Re:0.03～0.05%; P≤0.1%; S≤0.04%; Surplus is Fe.Its production technique is to utilize the medium-frequency induction furnace melting to prepare ductile iron grinding ball in conjunction with vacuum-evaporative pattern casting; Adopt the controlled chilling thermal treatment process that abrading-ball is heat-treated to obtain the bainite heterogeneous structure then; Carry out low-temperaturetempering at last.Prepared abrading-ball tissue is mainly acicular bainite and a small amount of martensite and residual austenite, surperficial average hardness HRC56～58 of abrading-ball, average-volume hardness HRC50～55, impelling strength α k value is at 16～20J/cm2, falling sphere number of times＞20000 time have extraordinary comprehensive mechanical property, wear resistance and impact fatigue life-span.Though such scheme has improved product performance to a certain extent, still fundamentally do not solve the problem that prior art exists.
Pump series products, especially ship's pump and mine pump accessory are worked in seawater and all kinds of severe environment for a long time, need superior corrosion resistance energy, wear resisting property and good intensity and plasticity and toughness.At present mainly adopt rich chromium cast iron to make the pump housing, processing difficulties, price height, plasticity and toughness are poor, corrosion resistance nature and work-ing life are undesirable; And make impeller by there being expensive defective with copper alloy.In addition, products such as drawing wire machine accessory such as roller are used to produce the automobile metal rod, are attrition component, need good wear resisting property.Currently used material is not to be difficult to satisfy to use required, and work-ing life is shorter, is exactly that cost is higher, is difficult to apply.
Summary of the invention
The objective of the invention is at the problems referred to above, a kind of excellent comprehensive performance that has is provided, be easy to processing and manufacturing, lower-cost isothermal quench bainitic ductile cast iron.
Another object of the present invention is at the problems referred to above, and a kind of long service life is provided, and low cost of manufacture has superior corrosion resistance energy, wear resisting property and good intensity and the pump class accessory of plasticity and toughness.
Another object of the present invention is at the problems referred to above, and a kind of long service life is provided, and low cost of manufacture has superior corrosion resistance energy, wear resisting property and good intensity and the drawing wire machine accessory of plasticity and toughness.
For achieving the above object, the present invention has adopted following technical proposal: this isothermal quench bainitic ductile cast iron is characterized in that the weight ratio of constituents of this isothermal quench bainitic ductile cast iron (wt%) is: 3.50～3.8%C, 2.2～2.7%Si, 0.2～0.5%Mn ,≤0.07%P ,≤0.03%S, 0.03～0.06%Mg, 0.01～0.04%Re, 0.45～0.75%Cu, surplus is Fe.
Mentioned component and weight ratio are selected in the invention for use, can reach following purpose: obtain cast pearlite ductile iron (P content＞50%) before the isothermal quenching, to cancel general normalizing operation, to enhance productivity; Guarantee matrix and mechanical property after the isothermal quenching, obtain the good quality production quality, to satisfy service requirements.Obtain as-cast pearlitic ductile iron, its chemical ingredients require generally should be: high-carbon, low silicon, Gao Meng, add alloy; Guarantee that matrix and mechanical property after the isothermal quenching should be: middle manganese, add alloy.Comprehensive the two need, and consider the economy produced in batches, the chemical ingredients of determining product require be: high-carbon, low silicon, middle manganese, add microalloy.Wherein adopt an amount of conventional alloy Cu, to replace alloying elements such as expensive Mo, Ni, reduced cost, helped improving the isothermal quenching effect, but also the reduction (performance requriements after the isothermal quenching) that has remedied the Mn amount is to obtaining the influence that as-cast pearlitic causes.
In above-mentioned isothermal quench bainitic ductile cast iron, the as-cast structure of this isothermal quench bainitic ductile cast iron is: 1～3 grade of nodularization rate, 5～7 grades of graphite sphere diameters, content of pearlite in alloy＞50%, iron phosphide eutectic and cementite total amount≤3%.
In above-mentioned isothermal quench bainitic ductile cast iron, the mechanical property of this isothermal quench bainitic ductile cast iron is: tension б
bBe at least 1000Mpa, surrender б
0.2Be at least 700Mpa, unit elongation δ is at least 5%, impact value a
KBe at least 80J/cm
2, hardness is at least 300～360HB.
Isothermal quench bainitic ductile cast iron is as the purposes of pump class accessory.Wherein, pump class accessory comprises the pump housing and impeller at least.Up to the present the various pump series products of China still continue to use common materials such as general rich chromium cast iron, copper alloy, the material cost height, and work-ing life is low, accessory turnover rate height.The ADI novel material not only has and has good comprehensive mechanical property, and has high-wearing feature, shock-resistance and erosion resistance preferably.Therefore after adopting the ADI novel material, the work-ing life and the technology retaining of China's pump series products will be improved significantly; Especially on the pump series products that under severe environment, uses, can replace original high-abrasive material and copper alloy and make the pump housing and impeller.When improving pump series products work-ing life, also can reduce expensive alloying element consumption and non-ferrous metal consumption like this, reduce manufacturing cost and use cost greatly.
Isothermal quench bainitic ductile cast iron is as the purposes of drawing wire machine accessory.Wherein, the drawing wire machine accessory comprises pulley at least.Because isothermal quench bainitic ductile cast iron has good wear resistance, the structural strength height can effectively reduce manufacturing cost and use cost.
Compared with prior art, isothermal quench bainitic ductile cast iron and advantages of application thereof are: 1, have excellent comprehensive performance, be easy to processing and manufacturing, cost is lower; 2, long service life, low cost of manufacture has superior corrosion resistance energy, wear resisting property and good intensity and plasticity and toughness; 3, the suitability for industrialized production of isothermal quench bainitic ductile cast iron on the pump series products, especially the use on ship's pump and mine pump product, and improved the product performance of these two industries effectively in the purposes of drawing wire machine accessory, can bring huge economic benefit.
Embodiment
Embodiment 1: the weight ratio of constituents of isothermal quench bainitic ductile cast iron (wt%) is: 3.50～3.8%C, 2.2～2.7%Si, 0.2～0.5%Mn, ≤ 0.07%P ,≤0.03%S, 0.03～0.06%Mg, 0.01～0.04%Re, 0.45～0.75%Cu, surplus is Fe.The as-cast structure of isothermal quench bainitic ductile cast iron is: 1～3 grade of nodularization rate, 5～7 grades of graphite sphere diameters, content of pearlite in alloy＞50%, iron phosphide eutectic and cementite total amount≤3%.Mechanical property is: tension б
bBe at least 1000Mpa, surrender б
0.2Be at least 700Mpa, unit elongation δ is at least 5%, impact value a
KBe at least 80J/cm
2, hardness is at least 300～360HB.In actual applications, can adopt the arbitrary numerical value (also can comprise end value) in the weight ratio of constituents of above-mentioned each component to produce.
During production, in the isothermal quenching process, the control of workpiece deformation amount is the link of outbalance.Can adopt the charging mode when changing heating to solve.Tempering helps obtaining tempered structure, the raising unit elongation of grain refining, and can effectively eliminate internal stress.But after adopting the isothermal quenching technique of above-mentioned as-cast pearlitic tissue, its austenitizing and isothermal transformation all relatively fully there is no need in addition tempering again, have so not only simplified production process, have also reduced manufacturing cost simultaneously.If the isothermal quenching austenitizing of above-mentioned ferritic structure is insufficient, adopt the tempering effect also very small, even because tempering process is appropriate, also can only remedy the deficiency in its isothermal transformation.
Embodiment 2:
Present embodiment is with the purposes of isothermal quench bainitic ductile cast iron as pump class accessory.Pump class accessory comprises the pump housing and impeller at least.All the other and embodiment 1 roughly the same, this paper does not give unnecessary details at this.
Weight reaches 110kg after the general mine pump pump housing roughing, and wall thickness very inhomogeneous (heavy wall place be 45mm, thin-walled place for only 15mm) will reach the homogeneity of mechanical property and hardness, all has very big technical difficulty.Adopt following thermal treatment process: preheating, insulation, quench (rise and quench), successfully produced the qualified lower bainite spheroidal graphite cast iron pump housing, difference of hardness is controlled at interior (HB280 of heavy wall place～290, the HB320 of thin-walled place～330, the coupon HB330) mechanical property of HB50 scope and has also reached technical requirements.
Embodiment 3:
Present embodiment is with the purposes of isothermal quench bainitic ductile cast iron as the drawing wire machine accessory.The drawing wire machine accessory comprises pulley at least.The heat treated target value of drawing wire machine accessory is to obtain stable upper bainite tissue, and wherein 1～3 grade of lower bainite length, 1～2 grade of white area quantity, ferrite quantity 1～2 grade (JB3021-81) meet the requirements of mechanical property with workpiece after guaranteeing thermal treatment.The technology of Heating temperature and heat preservation method and isothermal treatment temperatures and isothermal time can address the above problem when formulating rational austenitizing.Austenitizing carries out in having the cabinet-type electric furnace of protective atmosphere.Isothermal processes is carried out in having the salt bath furnace that refrigeration cycle waterpipe and pressurized air stirs, and adopts saltpetre, SODIUMNITRATE and the formulated salt made from earth containing a comparatively high percentage of sodium chloride of Sodium Nitrite, keeps about 1% moisture, workpiece delivery time≤20 second.
Specific embodiment described herein only is that the present invention's spirit is illustrated.The technician of the technical field of the invention can make various modifications or replenishes or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.
Although this paper has used more term morely, do not get rid of the possibility of using other term.Using these terms only is in order to describe and explain essence of the present invention more easily; They are construed to any additional restriction all is contrary with spirit of the present invention.
Claims (7)
1. isothermal quench bainitic ductile cast iron, it is characterized in that, the weight ratio of constituents of this isothermal quench bainitic ductile cast iron (wt%) is: 3.50～3.8%C, 2.2～2.7%Si, 0.2～0.5%Mn, ≤ 0.07%P, ≤ 0.03%S, 0.03～0.06%Mg, 0.01～0.04%Re, 0.45～0.75%Cu, surplus is Fe.
2. isothermal quench bainitic ductile cast iron according to claim 1, it is characterized in that the as-cast structure of this isothermal quench bainitic ductile cast iron is: 1～3 grade of nodularization rate, 5～7 grades of graphite sphere diameters, content of pearlite in alloy＞50%, iron phosphide eutectic and cementite total amount≤3%.
3. isothermal quench bainitic ductile cast iron according to claim 1 is characterized in that the mechanical property of this isothermal quench bainitic ductile cast iron is: tension б
bBe at least 1000Mpa, surrender б
0.2Be at least 700Mpa, unit elongation δ is at least 5%, impact value a
KBe at least 80J/cm
2, hardness is at least 300～360HB.
As any described isothermal quench bainitic ductile cast iron in the claim 1～3 as the purposes of pump class accessory.
5. isothermal quench bainitic ductile cast iron as claimed in claim 4 is as the purposes of pump class accessory, and described pump class accessory comprises the pump housing and impeller at least.
As any described isothermal quench bainitic ductile cast iron in the claim 1～3 as the purposes of drawing wire machine accessory.
7. isothermal quench bainitic ductile cast iron as claimed in claim 6 is as the purposes of drawing wire machine accessory, and described drawing wire machine accessory comprises pulley at least.
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101602433B (en) * | 2009-07-01 | 2011-10-12 | 宣化冶金工业有限责任公司 | Scraper of CuNiMo alloying isothermal quenching ductile iron scraper conveyor and preparation method |
| CN102284652A (en) * | 2011-05-19 | 2011-12-21 | 重庆顺财钢锹制造有限公司 | Process for processing steel spade by using waste iron rail |
| CN103014478A (en) * | 2012-12-18 | 2013-04-03 | 鞍钢集团矿业公司 | Short-process semi-solid cast wear-resistant ball and manufacturing method thereof |
| CN103981434A (en) * | 2014-05-28 | 2014-08-13 | 河南理工大学 | Preparation method for high-toughness nodular cast iron |
| CN105543642A (en) * | 2016-02-03 | 2016-05-04 | 上海大学兴化特种不锈钢研究院 | Isothermal quenching nodular cast iron alloy material for wheels in urban rail transit |
| CN105695852A (en) * | 2016-02-15 | 2016-06-22 | 焦作固德联合机械制造有限公司 | Casting method for concrete pump truck bent pipe |
| CN107756725A (en) * | 2017-10-23 | 2018-03-06 | 广东现代铸造有限公司 | A kind of the plate spheroidal graphite cast-iron of injection machine two and the plate of injection machine two |
| CN110257695A (en) * | 2019-07-08 | 2019-09-20 | 北京工业大学 | A kind of cupric CADI wear-resistant material and its heat treatment process |
| CN110527899A (en) * | 2019-07-09 | 2019-12-03 | 南通市嘉诚机械有限公司 | A kind of ductile cast iron material applied on antidetonation high intensity water-cooling middle |
| CN111172451A (en) * | 2019-11-18 | 2020-05-19 | 莱州新忠耀机械有限公司 | High-hardness high-toughness constant-force collapsibility iron casting for petroleum drilling protection and manufacturing method thereof |
| CN113502431A (en) * | 2021-06-30 | 2021-10-15 | 东风商用车有限公司 | Isothermal quenching nodular cast iron material and preparation method and application thereof |
| CN114774644A (en) * | 2022-04-21 | 2022-07-22 | 武汉纺织大学 | ADI surface quenching process |
| CN115287526A (en) * | 2022-07-08 | 2022-11-04 | 东风商用车有限公司 | Nodular cast iron rocker arm and manufacturing method and application thereof |
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2008
- 2008-08-26 CN CNA2008101962662A patent/CN101348878A/en active Pending
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| CN101602433B (en) * | 2009-07-01 | 2011-10-12 | 宣化冶金工业有限责任公司 | Scraper of CuNiMo alloying isothermal quenching ductile iron scraper conveyor and preparation method |
| CN102284652A (en) * | 2011-05-19 | 2011-12-21 | 重庆顺财钢锹制造有限公司 | Process for processing steel spade by using waste iron rail |
| CN103014478A (en) * | 2012-12-18 | 2013-04-03 | 鞍钢集团矿业公司 | Short-process semi-solid cast wear-resistant ball and manufacturing method thereof |
| CN103981434A (en) * | 2014-05-28 | 2014-08-13 | 河南理工大学 | Preparation method for high-toughness nodular cast iron |
| CN103981434B (en) * | 2014-05-28 | 2015-12-02 | 河南理工大学 | A kind of preparation method of high tough spheroidal graphite cast iron |
| CN105543642A (en) * | 2016-02-03 | 2016-05-04 | 上海大学兴化特种不锈钢研究院 | Isothermal quenching nodular cast iron alloy material for wheels in urban rail transit |
| CN105543642B (en) * | 2016-02-03 | 2017-08-29 | 上海大学兴化特种不锈钢研究院 | Urban track traffic wheel austempering ductile iron alloy material |
| CN105695852A (en) * | 2016-02-15 | 2016-06-22 | 焦作固德联合机械制造有限公司 | Casting method for concrete pump truck bent pipe |
| CN107756725A (en) * | 2017-10-23 | 2018-03-06 | 广东现代铸造有限公司 | A kind of the plate spheroidal graphite cast-iron of injection machine two and the plate of injection machine two |
| CN110257695A (en) * | 2019-07-08 | 2019-09-20 | 北京工业大学 | A kind of cupric CADI wear-resistant material and its heat treatment process |
| CN110257695B (en) * | 2019-07-08 | 2020-07-17 | 北京工业大学 | Copper-containing CADI (copper-activated carbon dioxide) wear-resistant material and heat treatment process thereof |
| CN110527899A (en) * | 2019-07-09 | 2019-12-03 | 南通市嘉诚机械有限公司 | A kind of ductile cast iron material applied on antidetonation high intensity water-cooling middle |
| CN111172451A (en) * | 2019-11-18 | 2020-05-19 | 莱州新忠耀机械有限公司 | High-hardness high-toughness constant-force collapsibility iron casting for petroleum drilling protection and manufacturing method thereof |
| CN113502431A (en) * | 2021-06-30 | 2021-10-15 | 东风商用车有限公司 | Isothermal quenching nodular cast iron material and preparation method and application thereof |
| CN114774644A (en) * | 2022-04-21 | 2022-07-22 | 武汉纺织大学 | ADI surface quenching process |
| CN115287526A (en) * | 2022-07-08 | 2022-11-04 | 东风商用车有限公司 | Nodular cast iron rocker arm and manufacturing method and application thereof |
| CN115839399A (en) * | 2022-09-14 | 2023-03-24 | 广东极亚精机科技有限公司 | Harmonic speed reducer rigid gear and preparation method and application thereof |
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Open date: 20090121 |