阅读说明：本技术 一种疏浚船用锁圈及其制造方法 (It is a kind of to dredge retainer peculiar to vessel and its manufacturing method ) 是由 薛冰 殷凤仕 申发磊 李兆森 管浩 于 2019-08-30 设计创作，主要内容包括：本发明属于船用机器材料技术领域,具体涉及一种疏浚船用锁圈及其制造方法。所述锁圈,化学成分按质量百分比计为：C0.18～0.24％,Si0.30～0.60％,Mn0.80～1.20％,Cr0.50～1.30％,Ni0.70～0.80％,Mo0.50～0.90％,S<0.025％,P<0.10％,余量为Fe和不可避免的杂质；其制造方法包括如下步骤：(1)配料,(2)熔炼,(3)铸造,(4)热处理,(5)机加工。本发明疏浚船用锁圈经最终热处理后,组织为板条状铁素体上弥散分布球状碳化物的回火索氏体,既具有良好的塑韧性,又兼具高的硬度和耐磨性,能满足高性能疏浚船锁圈的使用要求；其制造方法简单易行。(The invention belongs to ship's machinery field of material technology, and in particular to a kind of to dredge retainer peculiar to vessel and its manufacturing method.The retainer, chemical component is by mass percentage are as follows: C0.18~0.24%, Si0.30~0.60%, Mn0.80~1.20%, Cr0.50~1.30%, Ni0.70~0.80%, Mo0.50~0.90%, S < 0.025%, P < 0.10%, surplus are Fe and inevitable impurity；Its manufacturing method includes the following steps: (1) ingredient, (2) melting, (3) casting, (4) heat treatment, (5) machining.The present invention dredges retainer peculiar to vessel after final heat treatment, organizes not only to have good plasticity and toughness for the tempered sorbite of Dispersed precipitate globular carbide on lath-shaped ferrite, but also have both high hardness and wearability, be able to satisfy the requirement of high-performance dredger ship retainer；Its manufacturing method is simple and easy.)

1. a kind of dredging retainer peculiar to vessel, it is characterised in that: chemical component is by mass percentage are as follows:

C0.18~0.24%, Si0.30~0.60%, Mn0.80~1.20%, Cr0.50~1.30%, Ni0.70~ 0.80%, Mo0.50~0.90%, S < 0.025%, P < 0.10%, surplus are Fe and inevitable impurity.

2. dredging retainer peculiar to vessel described in claim 1, it is characterised in that: the microstructure of the dredging retainer peculiar to vessel is plate The tempered sorbite of Dispersed precipitate globular carbide on ferrite banding.

3. a kind of manufacturing method of dredging retainer peculiar to vessel of any of claims 1 or 2, it is characterised in that: the following steps are included:

(1) ingredient: alloy composition ingredient is pressed；

(2) melting: using middle frequency furnace to above-mentioned ingredient carry out melting, furnace charge is melting down, skim after, pour into steel ladle；

(3) cast: after pouring method addition inovulant in packet, casting obtains as cast condition retainer；

(4) it is heat-treated: the obtained as cast condition retainer of casting is heated to 600~650 DEG C of 1~2h of heat preservation, it is further continued for being warming up to 860~ 920 DEG C, 2~4 hours are kept the temperature, is then cooled to room temperature；610~650 DEG C are heated to, keeps the temperature 2~4 hours, then water cooling arrives Room temperature；

(5) it machines: after machined, obtaining product.

4. manufacturing method according to claim 3, it is characterised in that: in step (2), the smelting temperature be 1480~ 1510℃。

5. manufacturing method according to claim 3, it is characterised in that: in step (3), the inovulant is grey cast-iron Bits and steel cuttings.

6. manufacturing method according to claim 5, it is characterised in that: the dosage of the grey cast-iron bits is steel quality 1.2~1.7%.

7. manufacturing method according to claim 5, it is characterised in that: the dosage of the steel cuttings be steel quality 5~ 8%.

Technical field

The invention belongs to ship's machinery field of material technology, and in particular to a kind of to dredge retainer peculiar to vessel and its manufacturing method.

Background technique

Dredger ship is domestic and international common dredger, is responsible for clear digging water channel and rivers and creeks mud, so that other ships smoothly lead to It crosses.Dredger ship at work, needs that dredging pipe is fixed using retainer (Locking ring), due to most of time It needs to carry out operation on the sea, it requires that retainer can resist the impact and corrosion of seawater, and buffer function can be played.

It is needed recently as market and the development of shipbuilding technology, dredger ship is constantly sent out to large-scale and ultra-large type direction Exhibition, the volume of retainer peculiar to vessel also constantly increase, and this requires retainer materials higher intensity and toughness.It is existing quenched Steel, such as ZG34Cr2Ni2Mo, performance parameter are as follows: yield strength >=700MPa, tensile strength >=950MPa, elongation after fracture >= 12%, hardness HB >=240；Existing common middle low carbon steel, such as 45 steel, performance parameter are as follows: yield strength >=310MPa stretches Intensity >=570MPa, elongation after fracture >=15% (the newly organized metal material handbook of Xu Feng, Huang Yun, Anhui science tech publishing house, 2017).Quenched hardness of steel is enough and toughness is insufficient, and common middle low carbon steel toughness is enough and intensity is insufficient, and casting character is poor, casting It needs annealed technique to eliminate casting stress after making and refines crystal grain.

Therefore, this field needs a kind of with higher-strength and toughness and the good dredger ship retainer steel of casting character.

Summary of the invention

In view of the deficiencies of the prior art, the object of the present invention is to provide a kind of dredging retainer peculiar to vessel, there is higher-strength, tough Property, wearability, and casting character is good；It is scientific and reasonable present invention simultaneously provides its manufacturing method, it is simple and easy.

Dredging retainer peculiar to vessel of the present invention, chemical component is by mass percentage are as follows:

C0.18~0.24%, Si0.30~0.60%, Mn0.80~1.20%, Cr0.50~1.30%, Ni0.70~ 0.80%, Mo0.50~0.90%, S < 0.025%, P < 0.10%, surplus are Fe and inevitable impurity.

Wherein:

The microstructure of the dredging retainer peculiar to vessel is the tempering of Dispersed precipitate globular carbide on lath columnar ferrite Sorbite.

The manufacturing method of dredging retainer peculiar to vessel of the present invention, comprising the following steps:

(1) ingredient: alloy composition ingredient is pressed；

(2) melting: using middle frequency furnace to above-mentioned ingredient carry out melting, furnace charge is melting down, skim after, pour into steel ladle；

(3) cast: after pouring method addition inovulant in packet, casting obtains as cast condition retainer；

(4) it is heat-treated: the as cast condition retainer that casting obtains being heated to 600~650 DEG C of 1~2h of heat preservation, is further continued for being warming up to 860~920 DEG C, 2~4 hours are kept the temperature, is then cooled to room temperature；610~650 DEG C are heated to, keeps the temperature 2~4 hours, then water It is as cold as room temperature；

(5) it machines: after machined, obtaining product.

Wherein:

In step (2), the smelting temperature is 1480~1510 DEG C.

Preferably, step (2) is specific as follows:

Melting is carried out to above-mentioned ingredient using middle frequency furnace, sets tapping temperature as 1480~1510 DEG C；After furnace charge dissolved clarification It skims, detects raw water ingredient with spectrometer, testing result is underproof to be adjusted as required again；Detect qualified increasing middle frequency furnace Power pours into steel ladle after furnace temperature rises to 1480~1510 DEG C.

In step (3), the inovulant is that grey cast-iron is considered to be worth doing and steel cuttings, the dosage of grey cast-iron bits are steel quality 1.2~1.7%, the dosage of steel cuttings is the 5~8% of steel quality.

The selection of chemical composition reason of material therefor of the present invention is explained further below as follows:

It dredges carbon content and the addition nickel element of retainer peculiar to vessel by reducing and guarantees that material has high plasticity and toughness and resistance to Corrosion, addition silicon, manganese, chromium simultaneously cooperate heat-treatment processing process formation carbide dispersion-strengthened appropriate mutually higher to guarantee Intensity and hardness, addition silicon, manganese, molybdenum element improve the castability of steel to reduce gas hole defect, improve the coagulability of cast steel Energy.

Carbon containing (C) of cast steel, which is measured, to be increased, tensile strength (σ_b) and yield strength (σ_s) increase accordingly, elongation (δ) then under Drop.Phosphorus content is more than after 0.3%, and the plasticity of cast steel further declines with the increase of carbon content, and intensity improves less, bends It takes and intensity or even is also declined slightly, therefore, select mass fraction between 0.18~0.24% in steel of the present invention.

Silicon (Si) is necessary deoxidier, increases the silicon content in cast steel, can improve the deoxidation situation of molten steel and enhance In addition its ability for resisting secondary oxidation in tapping and casting process increases so as to prevent steel-casting from gas hole defect occurs The content of silicon can effectively improve the intensity and hardness of steel.But the content of silicon is higher, the plasticity and toughness of steel are poorer, because This, selects mass fraction between 0.30~0.60% in steel of the present invention.

Manganese (Mn) is also necessary deoxidier in steel-making, and moreover, manganese can also play the role of removing class oxygen element, Such as the element sulphur in steel.In addition, manganese is austenite former, the harden ability of steel can be significantly improved, increases the intensity of steel And hardness, reduce the ductile-brittle transition temperature of steel.But therefore the excessively high toughness plasticity that can reduce steel of manganese amount selects in steel of the present invention Mass fraction is between 0.80~1.20%.

Molybdenum (Mo) is remarkably improved the harden ability of steel, moreover it is possible to improve the mobility of cast steel, but molybdenum category precious metal, therefore select Between 0.50-0.90%.

Chromium (Cr) is the main alloy element for improving steel hardenability and temper resistance.Moreover, chromium can also improve steel Hardness strength and wearability, but will cause steel toughness and plasticity be deteriorated, therefore, selected in steel of the present invention mass fraction for Between 0.50~1.30%.

Nickel (Ni) is the corrosion resistance for improving steel and the advantageous elements of obdurability, and content is too low to have little effect.But nickel belongs to Precious metal should be used less as far as possible, therefore select mass fraction between 0.70~0.80% in steel of the present invention.

Sulphur (S), phosphorus (P) are used as impurity element, and mass fraction is controlled respectively in S < 0.025%, P < 0.10%.

The founding method of material therefor of the present invention is explained further below as follows:

Grey cast-iron bits provide external nucleus with steel cuttings for iron liquid, increase the core that iron liquid forms δ-Fe, keep crystal grain thin It is small, it is evenly distributed, peritectic reaction occurs as iron liquid is cooling, δ-Fe is changed into austenite, continues to cool down, the tendency of growing up of crystal grain Also more and more weaker, finally obtain the tiny pearlite matrix of crystal grain.Because the grey cast-iron bits amount of addition is less, through research graphite It is influenced in the presence of the performance on steel of the present invention smaller.

The heat-treatment protocol of material therefor of the present invention is explained further below as follows:

The casting that casting obtains is heated to 600~650 DEG C of 1~2h of heat preservation, is to change non-equilibrium microstructure in steel For statenchyma, while eliminating as-cast structure heredity and the pre-heat treatment as quenching technical.The purpose of quenching is to obtain entirely The lath martensite in portion and a small amount of remaining carbide, improve the intensity, hardness and wearability of steel.Quenching temperature is not too low To whole martensite, quenching temperature is excessively high to make coarse grains, also can waste of energy.The purpose of tempering is to eliminate quenching Stress obtains the good tempered sorbite of comprehensive mechanical property.Tempering temperature is lower than 610 DEG C, and carbide is insufficient to allow to analyse completely Out, and plasticity poor toughness, tempering temperature are higher than 650 DEG C, and the hardness of steel and wearability can be made to reduce.The type of cooling of tempering is selected Being selected as water cooling is to eliminate temper brittleness.

Compared with prior art, the invention has the following advantages:

1, the present invention dredges retainer peculiar to vessel after final heat treatment, organizes as Dispersed precipitate Spherical Carbon on lath-shaped ferrite The tempered sorbite of compound not only has good plasticity and toughness, but also has both high hardness and wearability, is able to satisfy high-performance dredger ship The requirement of retainer.

2, the manufacturing method of the present invention, it is scientific and reasonable, it is simple and easy.

Detailed description of the invention

Fig. 1 is the metallographic structure figure of the auxiliary ingot bar of casting of the present invention.

Specific embodiment

Below with reference to embodiment, the present invention will be further described.