Corrosion-resistant and wear-resistant composite steel and preparation method thereof

Abstract

The invention discloses corrosion-resistant and wear-resistant composite steel and a preparation method thereof, and belongs to the technical field of composite steel. The composite steel comprises the following chemical components in percentage by weight: 0.08% to 0.18% of C, 0.1% to 0.2% of Si, 1.3% to 2.7% of Mn, 0.45% to 0.65% of Cr, 1.5% to 2.5% of Ni, 0.03% to 0.08% of Re, 0.35% to 0.55% of Mo, 0.1% to 0.5% of Cu, 0.03% to 0.05% of Nb, 0.02% to 0.04% of Ti, 0.03% to 0.06% of Al, 0.02% to 0.05% of V, 0.2% to 0.35% of W, 0.03% to 0.15% of rare earth and the balance of Fe and inevitable impurities. The composite steel obtained through the preparation method is excellent in abrasion resistance and corrosion resistance, and the service life of the steel is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of composite steel materials, and in particular relates to a corrosion-resistant and wear-resistant composite steel material and a preparation method thereof. Background Art

[0002] As a major steel producer in the world, my country faces serious corrosion problems with its large-scale carbon steel (accounting for about 70%) and low-alloy steel (accounting for about 20%). Steel corrosion hazards are prevalent in daily life and almost all industries, especially steel used in infrastructure, which faces atmospheric corrosion day after day. How to significantly improve the atmospheric corrosion resistance of construction steel at low cost is a key issue in the development and promotion of new corrosion-resistant steel. Summary of the invention

[0003] The present invention provides a corrosion-resistant and wear-resistant composite steel material and a preparation method thereof, the purpose of which is to solve the technical problems raised in the above-mentioned background technology.

[0004] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0005] The invention discloses a corrosion-resistant and wear-resistant composite steel material, wherein the chemical composition weight ratio is as follows: C is 0.08% to 0.18%, Si is 0.1% to 0.2%, Mn is 1.3% to 2.7%, Cr is 0.45% to 0.65%, Ni is 1.5% to 2.5%, Re is 0.03% to 0.08%, Mo is 0.35% to 0.55%, Cu is 0.1% to 0.5%, Nb is 0.03% to 0.05%, Ti is 0.02% to 0.04%, Al is 0.03% to 0.06%, V is 0.02% to 0.05%, W is 0.2% to 0.35%, rare earth is 0.03% to 0.15%, and the balance is Fe and inevitable impurities.

[0006] A method for preparing the corrosion-resistant and wear-resistant composite steel as described above comprises the following steps:

[0007] Step 1: Pig iron, scrap iron and other alloying elements are mixed, and the raw materials are mixed by vibration mixing or ball milling; the mixed raw materials are then put into a furnace for melting at a temperature of 1500°C to 1600°C; after the molten steel is pretreated, oxygen is blown into the molten steel for decarburization until the carbon content is 0.08% to 0.18%;

[0008] Step 2: before tapping, the ladle is purged with argon gas, molten steel is injected into the ladle, and then the molten steel in the ladle is refined; the refined molten steel is poured through a continuous casting machine at a pouring temperature of 1350°C to 1450°C to obtain a steel billet;

[0009] Step 3: After the steel billet is fully automatically cut, it is slowly cooled. The slowly cooled steel billet is placed in an electric heating furnace for heating at a temperature of 850°C to 950°C for 5 hours. The heated steel billet is left to stand in the slow cooling pit for 48 hours until it reaches room temperature.

[0010] Step 4: adopt three-stage heating, the temperature of the first stage is controlled at 1050±20℃, the temperature of the second stage is controlled at 1150±20℃, the temperature of the soaking stage is controlled at 1170±20℃, the heating time is controlled at 11min / cm~13min / cm, the soaking time is controlled at 50min~60min, and the furnace temperature is controlled at 1120±20℃;

[0011] Step 5, hot rolling the steel billet through a hot rolling mill, and the final rolling temperature is 1120℃~1160℃; the hot-rolled steel is annealed by a three-stage constant temperature annealing and solution treatment process, first annealing at 980℃~1080℃, keeping warm for 1h~2h, then cooling to 830℃~920℃, keeping warm for 2h~3h, and then cooling to 730℃~810℃, keeping warm for 3h~4h; naturally cooling to room temperature to obtain a composite steel.

[0012] As a preferred technical solution of the present invention, the vibration mixing is to put the raw materials into a vibration tank and vibrate for 65 minutes to 85 minutes, with a vibration frequency of 50 Hz, an amplitude of 7 mm, a vibration force of 13000 N, and a power of 0.85 kW.

[0013] As a preferred technical solution of the present invention, the ball milling mixing is to place the raw materials on a planetary ball mill for wet grinding for 3.5h to 4.5h, the wet grinding medium is alcohol, the ball mill speed is 250rpm / min to 350rpm / min, and the ball-to-material mass ratio is 10:1.

[0014] As a preferred technical solution of the present invention, the desulfurizer used in the molten steel pretreatment includes lime powder, fluorite powder and aluminum powder; the added amount of the lime powder is 8kg / t to 13kg / t, the added amount of the fluorite powder is 0.9kg / t to 1.8kg / t, and the added amount of the aluminum powder is 0.4kg / t to 0.8kg / t.

[0015] As a preferred technical solution of the present invention, the hot rolling includes rough rolling and finish rolling; both rough rolling and finish rolling adopt reciprocating rolling method; the starting rolling temperature of the rough rolling is 1050±20℃, the final rolling temperature is 930±20℃, the first two passes are widened, and the first pass after widening adopts a large reduction rate of ≥30%, and the reduction amount of each rough rolling pass is ≥25mm; after rough rolling, the steel billet is cooled, the cooling water volume is 125L / min, the flushing time is 35S, and the final cooling temperature is 910±20℃; the finishing rolling has 6 to 8 rolling passes, the total reduction rate is ≥65%, the first pass reduction rate is ≥30%, the rolling speed is ≥7m / s, the starting rolling temperature is 850℃~950℃, and the final rolling temperature is 760℃~830℃; after finish rolling, the steel billet is water-cooled, the cooling rate is 35℃ / s~40℃ / s, the red-returning temperature is 650℃~730℃, and the upper and lower water ratio is 1.4.

[0016] The present invention has the following beneficial effects:

[0017] The composite steel prepared by the present invention not only greatly improves the corrosion resistance and wear resistance, but also can effectively slow down the corrosion rate, and can effectively prevent atmospheric corrosion without the need for surface spraying, has a long service life, and also reduces production costs, improves the economy of the enterprise, and can be widely used in complex steel structure assembled residential buildings, external decoration frames, container mobile houses, and factory-style laboratory buildings, etc.

[0018] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Embodiment 1:

[0021] A corrosion-resistant and wear-resistant composite steel, the chemical composition weight ratio of which is:

[0022] C is 0.08%, Si is 0.1%, Mn is 1.3%, Cr is 0.45%, Ni is 1.5%, Re is 0.03%, Mo is 0.35%, Cu is 0.1%, Nb is 0.03%, Ti is 0.02%, Al is 0.03%, V is 0.02%, W is 0.2%, rare earth is 0.03%, and the balance is Fe and inevitable impurities.

[0023] A method for preparing the corrosion-resistant and wear-resistant composite steel as described above comprises the following steps:

[0024] Step 1, mixing pig iron, scrap iron and other alloy elements, and mixing the raw materials by vibration mixing; then putting the mixed raw materials into the furnace for melting at a temperature of 1500°C; after the molten steel is pretreated, blowing oxygen into the furnace for decarburization until the carbon content is 0.08%; wherein, the vibration mixing is to put the raw materials into the vibration tank for 65 minutes, the vibration frequency is 50Hz, the amplitude is 7mm, the vibration force is 13000N, and the power is 0.85kW; in addition, the desulfurizer used in the molten steel pretreatment includes lime powder, fluorite powder and aluminum powder; the addition amount of lime powder is 8kg / t, the addition amount of fluorite powder is 0.9kg / t, and the addition amount of aluminum powder is 0.4kg / t;

[0025] Step 2: Before tapping, the ladle is purged with argon gas, molten steel is injected into the ladle, and then the molten steel in the ladle is refined; the refined molten steel is poured through a continuous casting machine at a pouring temperature of 1350° C. to obtain a steel billet;

[0026] Step 3: After the steel billet is fully automatically cut, it is slowly cooled. The steel billet after slow cooling is placed in an electric heating furnace for heating. The heating furnace temperature is 850°C and the heating time is 5 hours. The heated steel billet is left to stand in the slow cooling pit for 48 hours until it reaches room temperature.

[0027] Step 4: adopt three-stage heating, the temperature of the first stage is controlled at 1030°C, the temperature of the second stage is controlled at 1130°C, the temperature of the soaking stage is controlled at 1150°C, the heating time is controlled at 11min / cm, the soaking time is controlled at 50min, and the furnace temperature is controlled at 1100°C;

[0028] Step 5: hot rolling the steel billet through a hot rolling mill, with a final rolling temperature of 1120°C; the hot-rolled steel is annealed using a three-stage constant temperature annealing and solution treatment process, first annealing at 980°C, keeping warm for 1h, then cooling to 830°C, keeping warm for 2h, and then cooling to 730°C, keeping warm for 3h; naturally cooling to room temperature to obtain a composite steel; wherein, hot rolling includes rough rolling and finish rolling; both rough rolling and finish rolling adopt a reciprocating rolling method; the starting rolling temperature of rough rolling is 1030°C, the final rolling temperature is 910°C, the first two passes are widened, After widening, the first pass is rolled with a large reduction rate of ≥30%, and the reduction amount of each rough rolling pass is ≥25mm; after rough rolling, the steel billet is cooled, the cooling water volume is 125L / min, the flushing time is 35S, and the final cooling temperature is 890℃; the finishing rolling passes are 6, the total reduction rate is ≥65%, the first pass reduction rate is ≥30%, the rolling speed is ≥7m / s, the starting rolling temperature is 850℃, and the final rolling temperature is 760℃; after finishing rolling, the steel billet is water-cooled, the cooling rate is 35℃ / s, the red-returning temperature is 650℃, and the upper and lower water ratio is 1.4.

[0029] Embodiment 2:

[0030] A corrosion-resistant and wear-resistant composite steel, the chemical composition weight ratio of which is:

[0031] C is 0.14%, Si is 0.15%, Mn is 2%, Cr is 0.55%, Ni is 2%, Re is 0.05%, Mo is 0.45%, Cu is 0.35%, Nb is 0.04%, Ti is 0.03%, Al is 0.045%, V is 0.035%, W is 0.3%, rare earth is 0.08%, and the balance is Fe and inevitable impurities.

[0032] A method for preparing the corrosion-resistant and wear-resistant composite steel as described above comprises the following steps:

[0033] Step 1, mixing pig iron, scrap iron and other alloy elements, and mixing the raw materials by vibration mixing; then putting the mixed raw materials into the furnace for melting at a temperature of 1550°C; after the molten steel is pretreated, blowing oxygen into the furnace for decarburization until the carbon content is 0.13%; wherein, the vibration mixing is to put the raw materials into a vibration tank for 75 minutes, the vibration frequency is 50Hz, the amplitude is 7mm, the vibration force is 13000N, and the power is 0.85kW; in addition, the desulfurizer used in the molten steel pretreatment includes lime powder, fluorite powder and aluminum powder; the addition amount of lime powder is 10kg / t, the addition amount of fluorite powder is 1.4kg / t, and the addition amount of aluminum powder is 0.65kg / t;

[0034] Step 2: Before tapping, the ladle is purged with argon gas, molten steel is injected into the ladle, and then the molten steel in the ladle is refined; the refined molten steel is poured through a continuous casting machine at a pouring temperature of 1400° C. to obtain a steel billet;

[0035] Step 3: After the steel billet is fully automatically cut, it is slowly cooled. The slowly cooled steel billet is placed in an electric heating furnace for heating at a temperature of 900°C for 5 hours. The heated steel billet is left to stand in the slow cooling pit for 48 hours until it reaches room temperature.

[0036] Step 4: adopt three-stage heating, the temperature of the first stage is controlled at 1050°C, the temperature of the second stage is controlled at 1150°C, the temperature of the soaking stage is controlled at 1170°C, the heating time is controlled at 12min / cm, the soaking time is controlled at 55min, and the furnace temperature is controlled at 1120°C;

[0037] Step 5: hot rolling the steel billet through a hot rolling mill, with a final rolling temperature of 1145°C; the hot-rolled steel is annealed using a three-stage constant temperature annealing and solution treatment process, first annealing at 1030°C, holding for 1.5 hours, then cooling to 880°C, holding for 2.5 hours, and then cooling to 770°C, holding for 3.5 hours; naturally cooling to room temperature to obtain a composite steel; wherein, hot rolling includes rough rolling and finish rolling; both rough rolling and finish rolling adopt a reciprocating rolling method; the starting rolling temperature of rough rolling is 1050°C, the final rolling temperature is 930°C, and the first two passes are extended width, after widening, the first pass adopts a large reduction rate rolling of ≥30%, and the reduction amount of each rough rolling pass is ≥25mm; after rough rolling, the billet is cooled, the cooling water volume is 125L / min, the flushing time is 35S, and the final cooling temperature is 910℃; the finishing rolling passes are 7 passes, the total reduction rate is ≥65%, the first pass reduction rate is ≥30%, the rolling speed is ≥7m / s, the starting rolling temperature is 900℃, and the final rolling temperature is 795℃; after finishing rolling, the billet is water-cooled, the cooling rate is 37.5℃ / s, the red-returning temperature is 690℃, and the upper and lower water ratio is 1.4.

[0038] Embodiment three:

[0039] A corrosion-resistant and wear-resistant composite steel, the chemical composition weight ratio of which is:

[0040] C is 0.18%, Si is 0.2%, Mn is 2.7%, Cr is 0.65%, Ni is 2.5%, Re is 0.08%, Mo is 0.55%, Cu is 0.5%, Nb is 0.05%, Ti is 0.04%, Al is 0.06%, V is 0.05%, W is 0.35%, rare earth is 0.15%, and the balance is Fe and inevitable impurities.

[0041] A method for preparing the corrosion-resistant and wear-resistant composite steel as described above comprises the following steps:

[0042] Step 1: Mix the pig iron, scrap iron and other alloying elements, and mix the raw materials by ball milling; then put the mixed raw materials into the furnace for melting at a temperature of 1600°C; after the molten steel is pretreated, blow oxygen into it for decarburization until the carbon content is 0.18%; wherein, the ball milling mixing is to place the raw materials on a planetary ball mill for wet grinding for 4.5 hours, the wet grinding medium is alcohol, the ball mill speed is 350rpm / min, and the ball-to-material mass ratio is 10:1; in addition, the desulfurizers used in the molten steel pretreatment include lime powder, fluorite powder and aluminum powder; the addition amount of lime powder is 13kg / t, the addition amount of fluorite powder is 1.8kg / t, and the addition amount of aluminum powder is 0.8kg / t;

[0043] Step 2: Before tapping, the ladle is purged with argon gas, molten steel is injected into the ladle, and then the molten steel in the ladle is refined; the refined molten steel is poured through a continuous casting machine at a pouring temperature of 1450° C. to obtain a steel billet;

[0044] Step 3: After the steel billet is fully automatically cut, it is slowly cooled. The slowly cooled steel billet is placed in an electric heating furnace for heating at a temperature of 950°C for 5 hours. The heated steel billet is left to stand in the slow cooling pit for 48 hours until it reaches room temperature.

[0045] Step 4: adopt three-stage heating, the temperature of the first stage is controlled at 1070℃, the temperature of the second stage is controlled at 1170℃, the temperature of the soaking stage is controlled at 1190℃, the heating time is controlled at 13min / cm, the soaking time is controlled at 60min, and the furnace temperature is controlled at 1140℃;

[0046] Step 5: hot rolling the steel billet through a hot rolling mill, with a final rolling temperature of 1160°C; the hot-rolled steel is annealed using a three-stage constant temperature annealing and solution treatment process, first annealing at 1080°C, keeping warm for 2h, then cooling to 920°C, keeping warm for 3h, and then cooling to 810°C, keeping warm for 4h; naturally cooling to room temperature to obtain a composite steel; wherein, hot rolling includes rough rolling and finish rolling; both rough rolling and finish rolling adopt a reciprocating rolling method; the starting rolling temperature of rough rolling is 1070°C, the final rolling temperature is 950°C, the first two passes are widened, After widening, the first pass is rolled with a large reduction rate of ≥30%, and the reduction amount of each rough rolling pass is ≥25mm; after rough rolling, the steel billet is cooled, the cooling water volume is 125L / min, the flushing time is 35S, and the final cooling temperature is 930℃; the finishing rolling passes are 8 passes, the total reduction rate is ≥65%, the first pass reduction rate is ≥30%, the rolling speed is ≥7m / s, the starting rolling temperature is 950℃, and the final rolling temperature is 830℃; after finishing rolling, the steel billet is water-cooled, the cooling rate is 40℃ / s, the red-returning temperature is 730℃, and the upper and lower water ratio is 1.4.

[0047] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A corrosion-resistant and wear-resistant composite steel material, characterized in that: The weight ratio of its chemical composition is: C is 0.08% to 0.18%, Si is 0.1% to 0.2%, Mn is 1.3% to 2.7%, Cr is 0.45% to 0.65%, Ni is 1.5% to 2.5%, Re is 0.03% to 0.08%, Mo is 0.35% to 0.55%, Cu is 0.1% to 0.5%, Nb is 0.03% to 0.05%, Ti is 0.02% to 0.04%, Al is 0.03% to 0.06%, V is 0.02% to 0.05%, W is 0.2% to 0.35%, rare earth is 0.03% to 0.15%, and the balance is Fe and unavoidable impurities.

2. A method for preparing the corrosion-resistant and wear-resistant composite steel material according to claim 1, characterized in that: The steps include: Step 1: Pig iron, scrap iron and other alloying elements are mixed, and the raw materials are mixed by vibration mixing or ball milling; the mixed raw materials are then put into a furnace for melting at a temperature of 1500°C to 1600°C; after the molten steel is pretreated, oxygen is blown into the molten steel for decarburization until the carbon content is 0.08% to 0.18%; Step 2: before tapping, the ladle is purged with argon gas, molten steel is injected into the ladle, and then the molten steel in the ladle is refined; the refined molten steel is poured through a continuous casting machine at a pouring temperature of 1350°C to 1450°C to obtain a steel billet; Step 3: After the steel billet is fully automatically cut, it is slowly cooled. The slowly cooled steel billet is placed in an electric heating furnace for heating at a temperature of 850°C to 950°C for 5 hours. The heated steel billet is left to stand in the slow cooling pit for 48 hours until it reaches room temperature. Step 4: adopt three-stage heating, the temperature of the first stage is controlled at 1050±20℃, the temperature of the second stage is controlled at 1150±20℃, the temperature of the soaking stage is controlled at 1170±20℃, the heating time is controlled at 11min / cm~13min / cm, the soaking time is controlled at 50min~60min, and the furnace temperature is controlled at 1120±20℃; Step 5, hot rolling the steel billet through a hot rolling mill, and the final rolling temperature is 1120℃~1160℃; the hot-rolled steel is annealed by a three-stage constant temperature annealing and solution treatment process, first annealing at 980℃~1080℃, keeping warm for 1h~2h, then cooling to 830℃~920℃, keeping warm for 2h~3h, and then cooling to 730℃~810℃, keeping warm for 3h~4h; naturally cooling to room temperature to obtain a composite steel.

3. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 2, characterized in that: The vibration mixing comprises putting the raw materials into a vibration tank and vibrating for 65 minutes to 85 minutes, with a vibration frequency of 50 Hz, an amplitude of 7 mm, a vibration force of 13000 N, and a power of 0.85 kW.

4. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 2, characterized in that: The ball milling mixing is to place the raw materials on a planetary ball mill for wet milling for 3.5 hours to 4.5 hours, the wet milling medium is alcohol, the ball mill speed is 250 rpm / min to 350 rpm / min, and the ball-to-material mass ratio is 10:

1.

5. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 3 or 4, characterized in that: The desulfurizer used in the molten steel pretreatment includes lime powder, fluorite powder and aluminum powder; the addition amount of the lime powder is 8kg / t to 13kg / t, the addition amount of the fluorite powder is 0.9kg / t to 1.8kg / t, and the addition amount of the aluminum powder is 0.4kg / t to 0.8kg / t.

6. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 5, characterized in that: The hot rolling includes rough rolling and finish rolling; both the rough rolling and the finish rolling adopt a reciprocating rolling method.

7. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 6, characterized in that: The starting rolling temperature of the rough rolling is 1050±20℃, the final rolling temperature is 930±20℃, the first two passes are widened, and the first pass after widening adopts a large reduction rate of ≥30%, and the reduction amount of each rough rolling pass is ≥25mm; after rough rolling, the steel billet is cooled, the cooling water volume is 125L / min, the flushing time is 35S, and the final cooling temperature is 910±20℃.

8. The method for preparing a corrosion-resistant and wear-resistant composite steel according to claim 6 or 7, characterized in that: The finishing rolling has 6 to 8 passes, with a total reduction rate of ≥65%, a first-pass reduction rate of ≥30%, a rolling speed of ≥7 m / s, a starting rolling temperature of 850°C to 950°C, and a final rolling temperature of 760°C to 830°C; after finishing rolling, the steel billet is water-cooled, with a cooling rate of 35°C / s to 40°C / s, a red-returning temperature of 650°C to 730°C, and an upper and lower water ratio of 1.4.