CN103436802B - The hot roll of rolling titanium plate and manufacture method thereof - Google Patents

The hot roll of rolling titanium plate and manufacture method thereof Download PDF

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CN103436802B
CN103436802B CN201310328831.7A CN201310328831A CN103436802B CN 103436802 B CN103436802 B CN 103436802B CN 201310328831 A CN201310328831 A CN 201310328831A CN 103436802 B CN103436802 B CN 103436802B
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hot roll
titanium plate
carried out
temper
roller stock
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CN103436802A (en
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杨昱东
高新生
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Sinosteel Xingtai Machinery and Mill Roll Co Ltd
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Sinosteel Xingtai Machinery and Mill Roll Co Ltd
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Abstract

The invention discloses a kind of hot roll and manufacture method thereof of rolling titanium plate, chemical composition in described hot roll and weight percentage are: C0.30 ~ 0.50%, Si0.60 ~ 2.00%, Mn0.20 ~ 1.00%, Cr4.50 ~ 6.00%, Ni0.05 ~ 0.65%, Mo1.00 ~ 2.00%, V0.50 ~ 1.50%, P≤0.025%, S≤0.020%, all the other are Fe and inevitable impurity; The manufacture method of the hot roll of described rolling titanium plate, comprises the processing steps such as refining steel ingot, forging roller stock, modifier treatment, induction quenching process and temper.Compared with the hot roll that the hot roll that the present invention produces and traditional C r3 material are made, wear resistance is good, and solidity to corrosion is strong, and heat crack resistance is strong, and the work-ing life of hot roll can improve more than 70%.

Description

The hot roll of rolling titanium plate and manufacture method thereof
Technical field
The present invention relates to a kind of roll and manufacture method thereof, specifically a kind of hot roll of rolling titanium plate and manufacture method thereof.
Background technology
Titanium has a series of excellent specific property, is widely used in the fields such as space flight, aviation, chemical industry, oil, metallurgy, light industry, electric power, sea water desaltination, naval vessels and daily life utensil.Titanium plate has high-strength low-density, good mechanical property, toughness and the feature such as corrosion resistance is good.Along with China's economy develops rapidly, more and more many to the demand of titanium and titanium alloys, to the surface quality of titanium plate and dimension precision requirement also more and more higher, the performance requriements therefore for the hot roll of rolling titanium plate is also more and more higher.
The material of the current hot roll being used for rolling titanium plate has part Cr2 material, main material is Cr3 series material, along with the raising to titanium plate specification of quality, the hot roll of this type of material can not have been met the need of market and the requirement of product surface high quality, reason comprise following some:
(1) hot roll of this serial material manufacture wears no resistance, roughness retaining capability is poor, the roll change cycle is short, change the production efficiency that hot roll seriously constrains rolling equipment frequently, increase the weight of the labour intensity of workman, simultaneously because the wearing and tearing of hot roll make roll shape hold facility poor, the titanium plate template causing rolling to obtain and dimensional precision are difficult to ensure, quality product declines;
(2) in the operation of rolling, because hot roll is iron and steel material quality, different from the electropotential of titanium plate, so the process systems that hot roll, titanium plate and Rolling Lubricant form also just has become a chemical primary cell system.In Rolling Production process, hot roll stands the galvanic corrosion under rolling stress condition and the stress fatigue effect under etching condition simultaneously, and body surface is easy to occur thermal crack, and lower machine stock removal is large, exacerbates roller consumption further, shortens roll campaign;
(3) thermal crack on hot roll surface is easy to print on titanium plate sheet material, and cause the board surface quality of titanium plate poor, scrap rate is high.
Therefore, along with the increase to titanium plate demand, need a kind of hot roll of new excellent performance.
Summary of the invention
The object of this invention is to provide a kind of hot roll and manufacture method thereof of rolling titanium plate, this hot roll has high-wearing feature, high roughness retaining capability and good solidity to corrosion.
For reaching above-mentioned performance requriements, the technical solution adopted in the present invention is:
The hot roll of rolling titanium plate, chemical composition in described hot roll and weight percentage are: C0.30 ~ 0.50%, Si0.60 ~ 2.00%, Mn0.20 ~ 1.00%, Cr4.50 ~ 6.00%, Ni0.05 ~ 0.65%, Mo1.00 ~ 2.00%, V0.50 ~ 1.50%, P≤0.025%, S≤0.020%, all the other are Fe and inevitable impurity.
Further improvement of the present invention is: the manufacture method of the hot roll of described rolling titanium plate comprises following processing step:
A, refining steel ingot: production desired raw material is being smelted into molten steel in electric arc furnace, molten steel is being placed in LF refining furnace and completes refining,
After liquid steel refining completes, be molded into electrode ingot, utilize electro-slag re-melting method founding to become steel ingot afterwards;
B, forging roller stock: by steel ingot after the forging process such as insulation, jumping-up and pulling make forging stock, carry out anneal, annealing temperature 620 ~ 720 DEG C, obtain roller stock by turning roughing afterwards;
C, modifier treatment: modifier treatment is carried out to the roller stock that step B obtains: quenching temperature is 900 ~ 960 DEG C, carries out temper afterwards, tempering temperature is 500 ~ 550 DEG C;
D, induction quenching process: surface induction hardening process is carried out to roller stock, heat-up rate during Quench heating is 100 ~ 200 DEG C/min, and final Heating temperature is 1000 ~ 1050 DEG C;
E, temper: the roller stock completing surface induction hardening process is carried out temper, tempering temperature is 520 ~ 650 DEG C, and soaking time is 50 ~ 80h;
After temper completes, according to the requirement size of hot roll, precision work is carried out to roller stock, obtain hot roll finished product, ultrasound examination, hardness test, microstructure examination are carried out to finished product.
Owing to have employed technique scheme, the technical progress acquired by the present invention is:
In the material composition of hot roll of the present invention, Cr can increase the depth of hardening zone of hot roll, improves hot roll intensity and wear resistance, reduces the tensile stress that thermal shocking causes, and steel can not be made to become fragile.Si can improve the thermal shocking drag of material and improve hardening capacity, can also improve steel belt roof bolt stability; The heat-resistant cracking of Mo content and roll working lining can have certain relation, increases content and can improve heat-resistant cracking when Mo content is lower, increases content heat-resistant cracking and reduce on the contrary during Mo content height; V is the element contributing to improving wearability carbide most, can the tissue of refinement steel and crystal grain, increases steel belt roof bolt stability after quenching.Add Cr, Ni as the composition of erosion resistance, improve the solidity to corrosion of hot roll, reduce the galvanic corrosion to hot roll in the operation of rolling.
Modifier treatment ensure that the overall flexibility of hot roll.Surface induction hardening thermal treatment is carried out to hot roll, rate of heating is that per minute raises 100 ~ 200 DEG C, and quenching temperature is 1000 ~ 1050 DEG C, higher than the quenching temperature of common material, controlled cooling model speed and translational speed, the unrelieved stress produced after reducing quenching process.Significantly reduced the generation probability of thermal crack after quench treatment by temper, and then promote anti-accident ability, extend the life cycle of hot roll.
Invention increases alloy Cr content, have adjusted the content of the alloying elements such as Si, Mo, V, and by specific heat treatment mode, the refinement crystal grain of steel, ensure the interior tissue even compact of hot roll, enhance the solidity to corrosion of hot roll, guarantee that hot roll has high roughness retaining capability and hot-cracking resistance.The hot roll adopting material of the present invention and performance to obtain, has high roughness retaining capability and hot-cracking resistance, under same working conditions, has high abrasion and hot-cracking resistance.Compared with the hot roll made with traditional C r3 material, wear resistance is good, and solidity to corrosion is strong, and heat crack resistance is strong, and the work-ing life of hot roll can improve more than 70%.
Embodiment
The hot roll of rolling titanium plate, the chemical composition in described hot roll and weight percentage are: C0.30 ~ 0.50%, Si0.60 ~ 2.00%, Mn0.20 ~ 1.00%, Cr4.50 ~ 6.00%, Ni0.05 ~ 0.65%, Mo1.00 ~ 2.00%, V0.50 ~ 1.50%, P≤0.025%, S≤0.020%; All the other are Fe and inevitable impurity.
The chemical composition of the hot roll of the rolling titanium plate and weight percentage thereof are preferably: C0.35 ~ 0.45%, Si0.80 ~ 1.50%, Mn0.60 ~ 0.80%, Cr4.80 ~ 5.50%, Ni0.25 ~ 0.50%, Mo1.20 ~ 1.50%, V0.70 ~ 1.00%, P≤0.020%, S≤0.015%; All the other are Fe and inevitable impurity.
Below in conjunction with embodiment, the present invention is described in further details:
Embodiment 1
The hot roll of rolling titanium plate, chemical composition in described hot roll and the design objective of weight percentage are: C0.30 ~ 0.35%, Si0.80 ~ 0.90%, Mn0.70 ~ 0.80%, Cr4.50 ~ 5.00%, Ni0.35 ~ 0.45%, Mo1.40 ~ 1.50%, V0.80 ~ 0.90%, P≤0.025%, S≤0.020%; All the other are Fe and inevitable impurity.
The manufacture method of described hot rolling titanium working roll comprises following processing step:
A, refining steel ingot: prepare raw materials for production according to above-mentioned chemical composition and weight percentage thereof, in electric arc furnace, carry out preliminary melting is molten steel, carry out refining, vacuum stripping at LF refining furnace to molten steel after melting completes, the molten steel after refining carries out pouring into a mould, being molded into electrode ingot;
After the electrode ingot obtained is carried out anneal, utilize electro-slag re-melting method that the founding of electrode ingot is become steel ingot.
Through carrying out chemical composition analysis to the steel ingot obtained, the chemical composition in steel ingot and weight percentage are: C0.35%, Si0.90%, Mn0.80%, Cr5.00%, Ni0.35%, Mo1.50%, V0.90%, P0.025%, S0.02%.
B, forging roller stock: heating steel ingot forges, and make forging stock through production process forgings such as insulation, jumping-up and pullings, be heated to be 1230 ~ 1300 DEG C in forging process, forging ratio is not less than 2.5;
Carry out forging rear annealing process to forging stock, annealing temperature 620 ~ 720 DEG C, finally carries out turning roughing, obtained roller stock.
C, modifier treatment: modifier treatment is carried out to the roller stock that step B obtains: the Heating temperature of quench treatment is 900 ~ 960 DEG C, water-cooled cooling after quenching; Carry out temper afterwards, tempering temperature is 500 ~ 550 DEG C.
D, induction quenching process: adopt double frequency or line-frequency induction circle induction heating mode to carry out surface induction hardening process to roller stock, heat-up rate during Quench heating is 100 ~ 200 DEG C/min, and outlet temperature is 1000 ~ 1050 DEG C, water-spraying control cooling afterwards.
E, temper: the roller stock completing surface induction hardening process is carried out temper, tempering temperature is 520 ~ 650 DEG C, and soaking time is 50 ~ 80h, and air cooling is to room temperature afterwards.
After temper completes, according to the requirement size of hot roll, precision work is carried out to roller stock, obtain hot roll finished product, ultrasound examination, hardness test, microstructure examination are carried out to finished product.
Measured by special roll Shore scleroscope, the surface hardness recording the Heat Working Rolls of the present embodiment is 72 ~ 75HSD.The hot roll that the present embodiment is produced, metallographic structure and metallurgical performance good, under equal rolling temperature and rolling load, the corrosion resistance nature of hot roll improves, and the probability producing thermal crack reduces by 80%, and roll campaign improves more than 80%.
Embodiment 2
In embodiment 2, processing step is in the same manner as in Example 1, is with the difference of embodiment 1:
The chemical composition of hot roll described in the present embodiment and the design objective of weight percentage thereof are: C0.40 ~ 0.45%, Si0.60 ~ 0.70%, Mn0.90 ~ 1.00%, Cr4.50 ~ 5.00%, Ni0.05 ~ 0.10%, Mo1.60 ~ 2.00%, V0.50 ~ 0.60%, P≤0.025%, S≤0.020%; All the other are Fe and inevitable impurity.
Carry out chemical composition analysis to the steel ingot that steps A obtains, the chemical composition in the steel ingot obtained and weight percentage thereof are: C0.45%, Si0.60%, Mn1.00%, Cr4.50%, Ni0.05%, Mo2.00%, V0.50%, P0.019%, S0.015%.
Measured by special roll Shore scleroscope, the surface hardness recording the Heat Working Rolls of the present embodiment is 73 ~ 75HSD.The hot roll that the present embodiment is produced, metallographic structure and metallurgical performance good, under equal rolling temperature and rolling load, the corrosion resistance nature of hot roll improves, and the probability producing thermal crack reduces by 80%, and roll campaign improves more than 80%.
Embodiment 3
In embodiment 3, processing step is in the same manner as in Example 1, is with the difference of embodiment 1:
The chemical composition of hot roll described in the present embodiment and the design objective of weight percentage thereof are: C0.30 ~ 0.35%, Si0.80 ~ 0.90%, Mn0.60 ~ 0.70%, Cr4.80 ~ 5.50%, Ni0.55 ~ 0.65%, Mo1.00 ~ 1.10%, V0.60 ~ 0.70%, P≤0.020%, S≤0.010%; All the other are Fe and inevitable impurity.
Carry out chemical composition analysis to the steel ingot that steps A obtains, the chemical composition in the steel ingot obtained and weight percentage thereof are: C0.30%, Si0.80%, Mn0.60%, Cr5.50%, Ni0.65%, Mo1.00%, V0.70%, P0.017%, S0.007%.
Measured by special roll Shore scleroscope, the surface hardness recording the Heat Working Rolls of the present embodiment is 72 ~ 74HSD.The hot roll that the present embodiment is produced, metallographic structure and metallurgical performance good, under equal rolling temperature and rolling load, the corrosion resistance nature of hot roll improves, and the probability producing thermal crack reduces by 75%, and roll campaign improves more than 75%.
Embodiment 4
In embodiment 4, processing step is in the same manner as in Example 1, is with the difference of embodiment 1:
The chemical composition of hot roll described in the present embodiment and the design objective of weight percentage thereof are: C0.30 ~ 0.40%, Si1.80 ~ 2.00%, Mn0.70 ~ 0.80%, Cr4.50 ~ 5.00%, Ni0.25 ~ 0.30%, Mo1.10 ~ 1.20%, V1.30 ~ 1.50%, P≤0.020%, S≤0.015%; All the other are Fe and inevitable impurity.
Carry out chemical composition analysis to the steel ingot that steps A obtains, the chemical composition in the steel ingot obtained and weight percentage thereof are: C0.40%, Si2.00%, Mn0.70%, Cr4.80%, Ni0.25%, Mo1.20%, V1.50%, P0.015%, S0.011%.
Measured by special roll Shore scleroscope, the surface hardness recording the Heat Working Rolls of the present embodiment is 71 ~ 73HSD.The hot roll that the present embodiment is produced, metallographic structure and metallurgical performance good, under equal rolling temperature and rolling load, the corrosion resistance nature of hot roll improves, and the probability producing thermal crack reduces by 70%, and roll campaign improves more than 70%.
Embodiment 5
In embodiment 4, processing step is in the same manner as in Example 1, is with the difference of embodiment 1:
The chemical composition of hot roll described in the present embodiment and the design objective of weight percentage thereof are: C0.40 ~ 0.50%, Si1.40 ~ 1.50%, Mn0.20 ~ 0.30%, Cr5.50 ~ 6.00%, Ni0.45 ~ 0.50%, Mo1.40 ~ 1.45%, V0.90 ~ 1.00%, P≤0.020%, S≤0.015%; All the other are Fe and inevitable impurity.
Carry out chemical composition analysis to the steel ingot that steps A obtains, the chemical composition in the steel ingot obtained and weight percentage thereof are: C0.50%, Si1.50%, Mn0.20%, Cr6.00%, Ni0.50%, Mo1.45%, V1.00%, P0.02%, S0.009%.
Measured by special roll Shore scleroscope, the surface hardness recording the Heat Working Rolls of the present embodiment is 70 ~ 72HSD.The hot roll that the present embodiment is produced, metallographic structure and metallurgical performance good, under equal rolling temperature and rolling load, the corrosion resistance nature of hot roll improves, and the probability producing thermal crack reduces by 70%, and roll campaign improves more than 70%.

Claims (1)

1. the hot roll of rolling titanium plate, it is characterized in that chemical composition in described hot roll and weight percentage are: C0.40 ~ 0.50%, Si1.40 ~ 1.50%, Mn0.20 ~ 0.30%, Cr5.50 ~ 6.00%, Ni0.45 ~ 0.50%, Mo1.40 ~ 1.45%, V0.90 ~ 1.00%, P≤0.020%; S≤0.015%; All the other are Fe and inevitable impurity;
The manufacture method of the hot roll of described rolling titanium plate, comprises following processing step:
A, refining steel ingot: production desired raw material is being smelted into molten steel in electric arc furnace, molten steel is being placed in LF refining furnace and completes refining, after liquid steel refining completes, be molded into electrode ingot, utilizing electro-slag re-melting method founding to become steel ingot afterwards;
B, forging roller stock: by steel ingot after the forging process such as insulation, jumping-up and pulling make forging stock, carry out anneal, annealing temperature 620 ~ 720 DEG C, obtain roller stock by turning roughing afterwards;
C, modifier treatment: modifier treatment is carried out to the roller stock that step B obtains: quenching temperature is 900 ~ 960 DEG C, carries out temper afterwards, tempering temperature is 500 ~ 550 DEG C;
D, induction quenching process: surface induction hardening process is carried out to roller stock, heat-up rate during Quench heating is 100 ~ 200 DEG C/min, and final Heating temperature is 1000 ~ 1050 DEG C;
E, temper: the roller stock completing surface induction hardening process is carried out temper, tempering temperature is 520 ~ 650 DEG C, and soaking time is 50 ~ 80h;
After temper completes, according to the requirement size of hot roll, precision work is carried out to roller stock, obtain hot roll finished product, ultrasound examination, hardness test, microstructure examination are carried out to finished product.
CN201310328831.7A 2013-07-31 2013-07-31 The hot roll of rolling titanium plate and manufacture method thereof Active CN103436802B (en)

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CN104099528B (en) * 2014-07-08 2016-04-13 宁波市鄞州文昌金属制品有限公司 A kind of special-shaped roll and preparation method thereof
CN105349746A (en) * 2015-11-10 2016-02-24 铜陵市明诚铸造有限责任公司 Thermal treatment process of cast steel roll
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CN113278893A (en) * 2021-05-31 2021-08-20 山东建筑大学 Steel composition for shield machine cutter under complex spring domain condition and preparation
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CN101974723A (en) * 2010-09-26 2011-02-16 中钢集团邢台机械轧辊有限公司 Impact-resistance double-roller roughing roll and manufacturing method thereof

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CN101880834A (en) * 2010-07-27 2010-11-10 中钢集团邢台机械轧辊有限公司 Cold roll with high abrasive resistance and high roughness retaining capability and manufacturing method thereof
CN101974723A (en) * 2010-09-26 2011-02-16 中钢集团邢台机械轧辊有限公司 Impact-resistance double-roller roughing roll and manufacturing method thereof

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