Method for preparing electric power fitting through combination of quenching partitioning and zinc impregnation and electric power fitting

Abstract

The invention provides a method for preparing an electric power fitting through combination of quenching partitioning and zinc impregnation and the electric power fitting. The electric power fitting comprises an electric power fitting body and a zinc impregnation layer on the surface of the electric power fitting body. The preparation raw materials of the electric power fitting body comprise steel and multi-component alloy, and the mass of the multi-component alloy is 2%-4% of the mass of the steel. According to the quenching partitioning-zinc impregnation composite electric power fitting, the surface of the electric power fitting is modified while the quenching partitioning electric power fitting is prepared, the mechanical property of electric power fitting steel is further improved, and the prepared quenching partitioning-zinc impregnation composite electric power fitting has better wear resistance and corrosion resistance; and the electric power fittings are not easy to wear and corrode in the transportation, assembly and use processes.

Description

Technical Field

[0001] The invention relates to the technical field of electric power fitting preparation, and in particular to a method for preparing electric power fittings by quenching and partitioning and zincizing composite, and the electric power fittings. Background Art

[0002] With the rapid economic development of modern society, industry and people's daily life have become heavily dependent on the production, transmission and safe operation of electricity. Electricity has become an indispensable part of people's lives, travel, and office work, and it is also the power source for the normal operation of enterprises. However, most UHV transmission lines are erected in open areas in the wild. Harsh environments such as strong winds, acid rain, and sandstorms can easily cause rapid wear of steel materials on the transmission lines, resulting in corrosion failure of the fittings in a short period of time. As the degree of rust increases, the ductility loss rate of steel materials on the transmission lines will greatly increase, and its strength will greatly decrease, which will greatly shorten the overall service life of the transmission lines, increase replacement and maintenance costs, and cause waste of resources. Therefore, how to improve the performance of power fittings has become a difficult problem that needs to be solved.

[0003] The Spe team of Colorado University of Mines and Metallurgy first proposed the quenching-partitioning (Q&P) heat treatment process, which heats 0.35C-1.3Mn-0.74Si to the austenite zone and keeps it warm. After it is completely austenitized, it is quickly cooled to M s -M f The steel is heated to a temperature TQ between Ms and Ms, and then heated to a certain temperature Tp above Ms for isothermal treatment, and then cooled to room temperature to obtain a multiphase structure composed of martensite and metastable austenite.

[0004] The patent application with publication number CN202010319605.2 discloses a method for manufacturing 980MPa grade cold-rolled Q&P steel, the composition percentage of the steel plate is: C: 0.18-0.21%, Mn: 1.8-2.1%, Si: 1.4-1.6%, Al: 0.02-0.06%, P≤0.02%, S≤0.01%, Nb: 0.04-0.06%, the balance is Fe and other unavoidable impurities. The preparation method includes smelting, hot rolling, annealing, pickling, cold rolling, and continuous annealing, and the steel plate performance tensile strength is 982-1065MPa and the elongation is 18.8-24.9%.

[0005] The patent application with publication number CN201810144307.7 discloses a 980MPa grade cold-rolled high-strength Q&P steel for automobiles and its production method. The steel composition percentage is C: 0.18-0.24%, Si: 0.6-1.3%, Mn: 1.6-2.4%, Nb: 0.04-0.07%, Als: 0.5-1.0%, P: 0.02-0.04%, S: ≤0.005%, and the balance is Fe and other unavoidable impurities. The preparation method includes smelting, hot rolling, annealing, pickling, cold rolling, and continuous annealing to obtain a steel plate with a yield strength of ≥550MPa, a tensile strength of ≥980MPa, and an elongation of ≥18%.

[0006] It can be seen from the above-mentioned prior art that quenched and partitioned steel has good yield strength and tensile strength. However, the Q&P steel produced based on the existing composition and process has low elongation, poor plasticity, poor wear resistance and corrosion resistance, and can no longer meet the requirements of UHV transmission line power fittings. Summary of the invention

[0007] The purpose of the present invention is to provide a method for preparing electric power fittings by quenching and partitioning and zincizing, and electric power fittings, so as to overcome the problems of poor surface wear resistance and poor body corrosion resistance of electric power fittings for overhead power transmission lines.

[0008] The present invention is achieved through the following technical solutions: An electric power fitting, comprising an electric power fitting body and a zinc-diffused layer on the surface of the electric power fitting body; The raw materials for preparing the power fitting body include steel and multi-element alloy, and the mass of the multi-element alloy is 2%-4% of the mass of the steel; The chemical composition of the steel includes, by mass fraction, C: 0.08% to 0.24%, Mn: 2.15% to 3.24%, Si: 1.40% to 1.60%, Al: ≤0.05%, Ti: 0.05% to 0.15%, P≤0.012%, S≤0.01%, Ni: 0.25% to 0.55%, Nb: 0.40% to 0.80%, Mo: 0.2% to 0.65%, W: 1% to 1.5%, and the balance is Fe and unavoidable impurities; The chemical composition of the multi-element alloy includes: Ce: 6.58%-7.24%, Ti: 15.32%-15.43%, Ca: 5.22%-5.60%, K: 5.52%-5.61%, Si: 10.53%-12.47%, and the balance is Fe and inevitable impurities.

[0009] Furthermore, Nb+Ni+Mo+W≤3.5%.

[0010] Furthermore, the raw material for preparing the sherardizing layer, the sherardizing agent, includes micron-sized zinc powder, Ce2O, activator NH4Cl and filler Al2O3, the activator NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, the filler Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is micron-sized zinc powder.

[0011] A method for preparing electric power fittings by quenching and partitioning and zincizing, comprising: Mixing scrap steel and steelmaking pig iron and heating them to melt, adding ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel and ferrotitanium after the molten steel is completely melted, heating to a first preset temperature, then adding ferroaluminum, heating the molten steel to a second preset temperature, adding multi-element alloy, and after the multi-element alloy is completely melted, slagging and allowing the molten steel to stand; When the temperature of the molten steel drops to a third preset temperature, casting, solidification, and cooling are performed to obtain a casting; When the surface temperature of the casting drops to a fourth preset temperature, the casting is taken out, and repeatedly heated and kept warm, and then cooled to room temperature to obtain the power fitting body; A zinc infiltration layer is prepared on the electric power fitting body to obtain the electric power fitting.

[0012] Furthermore, the repeated heating and heat preservation are specifically: reheating the casting to a fifth preset temperature and keeping it warm for a first preset time, then cooling it to a sixth preset temperature, keeping it warm for a second preset time, reheating it to a seventh preset temperature, and keeping it warm for a third preset time.

[0013] Further, the first preset temperature is 1540-1560°C; And / or, the second preset temperature is 1640-1680°C; And / or, the third preset temperature is 1500-1540° C.; And / or, the fourth preset temperature is 260-290°C And / or, the fifth preset temperature is 900-950° C.; And / or, the sixth preset temperature is 260-300° C.; And / or, the seventh preset temperature is 350-380°C.

[0014] Further, the first preset time is 1-2 hours; And / or, the second preset time is 2-4 hours; And / or, the third preset time is 2-4 hours.

[0015] Furthermore, the preparation of the zincizing layer on the electric power fitting body is specifically as follows: The electric power fitting body is heated to a first insulation temperature and kept at the first insulation time, and then cooled to room temperature; The cooled electric power fitting body is mixed with the zincizing agent, and then heated to a second insulation temperature and maintained for a second time to obtain the electric power fitting.

[0016] Further, the power fitting body is heated to a first insulation temperature and kept warm for a first time, and then cooled to room temperature, specifically: the power fitting body is heated to 880°C-1200°C at a heating rate of 4°C-10°C / min, kept warm for 30-240s, and then cooled to room temperature.

[0017] Further, the cooled electric power fitting body is mixed with the zincizing agent, and then heated to a second insulation temperature and kept warm for a second time to obtain the electric power fitting, specifically: The zincizing agent is mixed with the cooled electric power fittings, and the temperature is increased to 380°C-450°C at a heating rate of 4°C-10°C / min, and the temperature is kept for 1 hour-4 hours, and then cooled to room temperature to obtain the electric power fittings.

[0018] Furthermore, the sherardizing agent includes micron-sized zinc powder, Ce2O, activator NH4Cl and filler Al2O3, the activator NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, the filler Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is micron-sized zinc powder.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention adopts a quenching and partitioning and zinc infiltration composite process to prepare electric hardware. First, a steel material for electric hardware is designed. Starting from the base material of the electric hardware, the performance of the steel base material is improved. Then, the performance of the electric hardware steel is further improved through quenching and partitioning treatment. At the same time, when the steel is partitioned, the surface is modified by the zinc infiltration process. Compared with the traditional quenching and partitioning electric hardware preparation method, the present invention not only prepares the quenching and partitioning electric hardware, but also performs a modification treatment on the surface of the electric hardware, further improving the mechanical properties of the electric hardware steel. The prepared quenching and partitioning-zinc infiltration composite electric hardware has better wear resistance and corrosion resistance, and is less susceptible to wear and corrosion during the transportation, assembly and use of the electric hardware.

[0020] In addition, the steel prepared by the present invention has high strength and high plasticity, and the mechanical properties and elongation are improved at the same time. The improvement principle mainly lies in the following aspects: 1. The mechanical properties and plastic properties of the steel material itself are improved by rationally designing the material composition; 2. The mechanical properties and plastic properties of the steel material cannot be further improved by controlling the composition alone, and improving the mechanical properties and plastic properties through various post-processing is a common and effective means. Among them, the quenching and partitioning process can prepare a steel material with a mixed structure type of ferrite, martensite and residual austenite. Martensite has higher strength, while ferrite and residual austenite have higher plasticity. Therefore, this mixed structure prepared under the quenching and partitioning process enables the steel to have both good strength and plasticity; 3. In the present invention, in order to further improve the strength-plasticity matching of the steel material, that is, to have higher plasticity while improving the strength, the partitioning and the preparation of the zinc-diffusion layer are carried out simultaneously, which increases the partitioning time and greatly increases the ferrite content in the steel plate, thereby greatly improving the elongation of the steel plate. At the same time, since the prepared zinc-diffusion layer can improve the mechanical properties of the steel material, the mechanical properties and plasticity of the steel material are simultaneously improved. DETAILED DESCRIPTION

[0021] The present invention is described in detail below: The present invention starts from the traditional quenching and partitioning steel, first designs the steel composition, then performs quenching and partitioning treatment on the steel, and simultaneously performs zinc infiltration treatment on the surface of the steel material during the partitioning process to further improve the performance of the steel.

[0022] Firstly, the present invention provides an electric power fitting, which comprises an electric power fitting body and a zinc-diffused layer on the surface of the electric power fitting body; The raw materials for preparing the power fitting body include steel and multi-element alloy, and the mass of the multi-element alloy is 2%-4% of the mass of the steel; The chemical composition of the steel includes, by mass fraction, C: 0.08% to 0.24%, Mn: 2.15% to 3.24%, Si: 1.40% to 1.60%, Al: ≤0.05%, Ti: 0.05% to 0.15%, P≤0.012%, S≤0.01%, Ni: 0.25% to 0.55%, Nb: 0.40% to 0.80%, Mo: 0.2% to 0.65%, W: 1% to 1.5%, and the balance is Fe and unavoidable impurities; The chemical composition of the multi-element alloy includes: Ce: 6.58%-7.24%, Ti: 15.32%-15.43%, Ca: 5.22%-5.60%, K: 5.52%-5.61%, Si: 10.53%-12.47%, and the balance is Fe and inevitable impurities.

[0023] As a preferred embodiment, Nb+Ni+Mo+W≤3.5%.

[0024] As a preferred embodiment, the raw material for preparing the sherardizing layer, the sherardizing agent, includes micron-sized zinc powder, Ce2O, activator NH4Cl and filler Al2O3, the activator NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, the filler Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is micron-sized zinc powder.

[0025] The present invention also provides a method for preparing an electric power fitting by quenching and partitioning and zincizing, mainly preparing an electric power fitting body, performing quenching and partitioning on the electric power fitting body, and performing zincizing on the electric power fitting body, comprising: Mixing scrap steel and steelmaking pig iron and heating them to melt, adding ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel and ferrotitanium after the molten steel is completely melted, heating to a first preset temperature, then adding ferroaluminum, heating the molten steel to a second preset temperature, adding multi-element alloy, and after the multi-element alloy is completely melted, slagging and allowing the molten steel to stand; When the temperature of the molten steel drops to a third preset temperature, casting, solidification, and cooling are performed to obtain a casting; When the surface temperature of the casting drops to a fourth preset temperature, the casting is taken out, and repeatedly heated and kept warm, and then cooled to room temperature to obtain the power fitting body; A zinc infiltration layer is prepared on the electric power fitting body to obtain the electric power fitting.

[0026] Specifically, scrap steel is used as the main raw material, and the scrap steel and steel-making pig iron are first mixed and heated in an electric furnace to melt. After the molten steel is melted, ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel, and ferrotitanium are added. The present invention uses scrap steel as the main raw material, and scrap steel and steel-making pig iron are first mixed and heated in an electric furnace to melt. Since scrap steel and steel-making pig iron are mainly iron-based, and the content of other elements is relatively small, it cannot meet the actual production requirements. Therefore, after the molten steel is melted, additional materials such as ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel, and ferrotitanium are added to improve the hardness and wear resistance of the steel. The temperature is raised to 154 0-1560℃, then add aluminum iron, and control the chemical composition and mass fraction of the molten steel in the furnace to C: 0.08% ~ 0.24%, Mn: 2.15% ~ 3.24%, Si: 1.40% ~ 1.60%, Al: ≤ 0.05%, P ≤ 0.012%, S ≤ 0.01%, Ni: 0.25% ~ 0.55%, Nb: 0.40% ~ 0.80%, Mo: 0.2% ~ 0.65%, W: 1% ~ 1.5%, and Nb + Ni + Mo + W ≤ 3.5%, the balance is Fe and unavoidable impurities The molten steel is heated to 1640-1680℃ and then discharged from the furnace to the ladle; after all the molten steel enters the ladle, the multi-element alloy wire is sent to the molten steel in the ladle by a wire feeder, and the amount of multi-element alloy wire added accounts for 2%-4% of the mass of the molten steel entering the ladle; the chemical composition and mass fraction of the multi-element alloy wire are 6.58%-7.24% Ce, 15.32%-15.43% Ti, 5.22%-5.60% Ca, 5.52%-5.61% K, 10.5%3-12.47% Si, and the balance is Fe and unavoidable impurities; the multi-element alloy wire is used for the production of the molten steel. After all the gold wires are melted, the slag is removed and the molten steel is allowed to stand. When the temperature of the molten steel drops to 1500-1540℃, the molten steel is poured into the mold. After the molten steel solidifies in the mold and cools to 260-290℃ when the surface temperature of the casting drops to 2, the casting is taken out of the mold, and then the casting is reheated to 900-950℃. After keeping warm for 1-2 hours, it is taken out of the furnace and air-cooled to 260-300℃. After keeping warm for 2-4 hours, it is re-entered into the furnace and heated to 350-380℃. After keeping warm for 2-4 hours, it is taken out of the furnace and air-cooled to room temperature to eliminate internal stress, stabilize the structure, and obtain the main body of the power hardware.

[0027] Then, a zinc-diffusion layer is prepared on the power fitting body: first, the power fitting body is quenched, and the obtained power fitting body is heated in a muffle furnace at a heating rate of 4℃-10℃ / min, a holding temperature of 880℃-1200℃, and a holding time of 30-240s, and then cooled to room temperature to further improve the hardness of the power fitting body itself. Then, the power fitting body is partitioned, and a zinc-diffusion layer is prepared during the partitioning process. The zinc-diffusion agent and the power fitting body are placed in a zinc-diffusion tank, and the temperature is raised to 380℃-450℃ at a heating rate of 4℃-10℃ / min, and the holding time is 1 hour to 4 hours, and then cooled to room temperature, thereby generating a quenching partitioning zinc-diffusion layer on the power fitting body to obtain the power fitting. Among them, during the quenching and partitioning process, since different cooling rates will have a certain impact on the performance of the fitting and the zinc-diffusion layer, the cooling method during the quenching and partitioning process can be a combination of any one or more cooling methods of furnace cooling, air cooling, and water cooling. In addition, the zinc powder in the sherardizing agent during the distribution process is micron-grade zinc powder, with a zinc content of ≥98%, an activator of NH4Cl, a filler of Al2O3, and a small amount of Ce2O, wherein NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is zinc powder. The activator NH4Cl powder mainly promotes the diffusion of zinc atoms, and the filler Al2O3 prevents the powder from sticking. On this basis, adding Ce2O can further promote the diffusion rate of zinc atoms.

[0028] The distribution process can be carried out for multiple times, not limited to once. The zincizing agent is mixed by a planetary ball mill during preparation, and the mixing time is 1 hour to 2 hours.

[0029] The embodiments of the present invention will be described in detail below in conjunction with the examples. The implementation cases are preferred embodiments of the present invention and should not be used to limit the scope of the present invention. In the following examples, the methods and experimental equipment used are all conventional methods and instruments unless otherwise specified.

[0030] Example 1 The scrap steel is used as the main raw material. The scrap steel and the steel-making pig iron are first mixed and heated in an electric furnace to melt. After the molten steel is melted, ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel, ferrotitanium and ferroaluminum are added. The temperature is raised to 1540°C, and then ferroaluminum is added. The chemical composition and mass fraction of the molten steel in the furnace are controlled at C: 0.12%, Mn: 2.62%, Si: 1.52%, Al: 0.03%, Ti: 0.1%, P: 0.01%, S: 0.005%, Ni: 0.3%, Nb: 0.5%, Mo: 0.4%, W: 1.2%, and the balance is Fe and unavoidable impurities. Then the molten steel is heated to 1640°C and then taken out of the furnace into the ladle. After all the molten steel enters the ladle, a wire feeder is used to send the multi-element alloy wire into the molten steel in the ladle. The amount of the multi-element alloy wire added accounts for 3.5% of the mass of the molten steel entering the ladle. The chemical composition and mass fraction of the multi-element alloy wire are 6.72% Ce, 15.35% Ti, 5.45% Ca, 5.55% K, 11.65% Si, the balance is Fe and inevitable impurities; after all the multi-element alloy wires are melted, the slag is removed and the molten steel is allowed to stand. When the temperature of the molten steel drops to 1535°C, the molten steel is poured into the mold. After the molten steel solidifies in the mold and cools to when the surface temperature of the casting drops to 275°C, the casting is taken out of the mold, and then the casting is reheated to 920°C, kept warm for 2 hours, taken out of the furnace and air-cooled to a temperature of 270°C, kept warm for 2 hours, re-entered the furnace and heated to 360°C, kept warm for 2 hours, then taken out of the furnace and air-cooled to room temperature, and the power hardware body can be obtained.

[0031] Preparation of quenching and partitioning zinc-diffusion layer on the main body of the electric hardware: First, the obtained electric hardware body is quenched, and the electric hardware is heated in a muffle furnace at a heating rate of 6°C / min, a holding temperature of 930°C, and a holding time of 120s. Then, it is cooled to room temperature at a cooling rate of 15°C / min using water cooling to complete the quenching of the electric hardware. The zinc-diffusion agent is mixed in a mass fraction ratio of Zn: NH4Cl: Al2O3: Ce2O = 71%: 4%: 23%: 2%, and the ball milling time is 2 hours. The main body of the electric hardware and the zinc-diffusion agent are placed in a zinc-diffusion tank for zinc-diffusion, with a heating rate of 8°C / min, a holding temperature of 400°C, and a holding time of 2 hours. Then, it is cooled to room temperature with the furnace, and the partitioning process of the electric hardware and the preparation process of the zinc-diffusion layer are completed at the same time.

[0032] Example 2 With scrap steel as the main raw material, the scrap steel and steelmaking pig iron are first mixed and heated in an electric furnace to melt. After the molten steel is melted, ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel, ferrotitanium and ferroaluminum are added. The temperature is raised to 1540℃, and then ferroaluminum is added. The chemical composition and mass fraction of the molten steel in the furnace are controlled at C: 0.08%, Mn: 2.15%, Si: 1.40%, Al: 0.05%, Ti: 0.05%, P: 0.012%, S: 0.01%, Ni: 0.25%, Nb: 0.40%, Mo: 0.2%, W: 1%, the balance is Fe and inevitable impurities, then the molten steel is heated to 1640℃ and then taken out of the furnace into the ladle; after all the molten steel enters the ladle, the multi-element alloy wire is sent to the molten steel in the ladle by a wire feeder, and the amount of multi-element alloy wire added accounts for 2% of the mass of the molten steel entering the ladle; the chemical composition and mass fraction of the multi-element alloy wire are 6.58% Ce, 15.32% Ti, 5.22% Ca, 5 .52% K, 10.5% Si, the balance is Fe and inevitable impurities; after all the multi-element alloy wires are melted, the slag is removed and the molten steel is allowed to stand. When the temperature of the molten steel drops to 1500℃, the molten steel is poured into the mold. After the molten steel solidifies in the mold and cools to when the surface temperature of the casting drops to 260℃, the casting is taken out of the mold, and then the casting is reheated to 900℃, kept warm for 1 hour, taken out of the furnace and air-cooled to a temperature of 260℃, kept warm for 2 hours, re-entered the furnace and heated to 350℃, kept warm for 2 hours, then taken out of the furnace and air-cooled to room temperature, and the starting electrical hardware body can be obtained.

[0033] Preparation of quenching and partitioning zinc layer on the power fitting body: First, heat the obtained power fitting body in a muffle furnace, with a heating rate of 4℃ / min, a holding temperature of 880℃, and a holding time of 30s, and then cool it to room temperature with the furnace. The zincizing agent is mixed in a mass fraction ratio of Zn: NH4Cl: Al2O3: Ce2O = 77%: 2%: 20%: 1%, and the ball milling time is 1 hour. Put the power fitting body and the zincizing agent into the zincizing tank for zincizing, with a heating rate of 4℃ / min, a holding temperature of 380℃, and a holding time of 1 hour, and then cool it to room temperature with the furnace to obtain the power fitting.

[0034] Example 3 With scrap steel as the main raw material, the scrap steel and steel-making pig iron are first mixed and heated in an electric furnace to melt. After the molten steel is clear, ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel and ferrotitanium are added. The temperature is raised to 1560℃, and then ferroaluminum is added. The chemical composition and mass fraction of the molten steel in the furnace are controlled at C: 0.24%, Mn: 3.24%, Si: 1.6%, Al: 0.05%, Ti: 0.15%, P: 0.01%, S: 0.003%, Ni: 0.55%, Nb: 0.8%, Mo: 0.65%, W: 1.5%, and the balance is Fe and unavoidable impurities. The molten steel is then heated to 1680℃ and taken out of the furnace into the ladle. After all the molten steel enters the ladle, a wire feeder is used to send the multi-element alloy wire to the molten steel in the ladle. The amount of multi-element alloy wire added accounts for 4% of the mass fraction of the molten steel entering the ladle; the chemical composition and mass fraction of the multi-element alloy wire are 7.24% Ce, 15.43% Ti, 5.60% Ca, 5.61% K, 12.47% Si, and the remainder is Fe and inevitable impurities; after all the multi-element alloy wires are melted, the slag is removed and the molten steel is allowed to stand, and when the temperature of the molten steel drops to 1540°C, the molten steel is poured into the mold, and the molten steel solidifies in the mold and cools to when the surface temperature of the casting drops to 290°C, the casting is taken out of the mold, and then the casting is reheated to 950°C, kept warm for 2 hours, taken out of the furnace and air-cooled to a temperature of 270°C, kept warm for 4 hours, re-entered the furnace and heated to 380°C, kept warm for 4 hours, and then taken out of the furnace and air-cooled to room temperature, and the power hardware body can be obtained.

[0035] Preparation of quenching and partitioning zinc-plating layer on power fittings: First, heat the obtained power fitting body in a muffle furnace, with a heating rate of 10℃ / min, a holding temperature of 1200℃, and a holding time of 240s, and then cool it to room temperature with the furnace. The zinc-plating agent is mixed in a mass fraction ratio of Zn: NH4Cl: Al2O3: Ce2O = 61%: 6%: 30%: 3%, and the ball milling time is 1 hour. Put the power fitting body and the zinc-plating agent into the zinc-plating tank for zinc-plating, with a heating rate of 10℃ / min, a holding temperature of 450℃, and a holding time of 4 hours, and then cool it to room temperature with the furnace to obtain the power fittings.

[0036] In the above embodiment, the quenching method is specifically as follows: heating to the holding temperature at a set heating rate, holding for a set time, and then cooling to room temperature at a set cooling rate by water cooling for quenching. In order to simplify the experimental process, the distribution and sherardizing processes are processed simultaneously, that is, as described below: the power fitting body and the sherardizing agent are placed in the sherardizing tank for sherardizing, heating, keeping warm, and then cooling to room temperature with the furnace. In this process, the distribution and sherardizing layer preparation of the power fitting are completed.

[0037] Comparative Example With scrap steel as the main raw material, the scrap steel and steel-making pig iron are first mixed and heated in an electric furnace to melt. After the molten steel is clear, ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel and ferrotitanium are added. The temperature is raised to 1560℃, and then ferroaluminum is added. The chemical composition and mass fraction of the molten steel in the furnace are controlled at C: 0.24%, Mn: 3.24%, Si: 1.6%, Al: 0.05%, Ti: 0.15%, P: 0.01%, S: 0.003%, Ni: 0.55%, Nb: 0.8%, Mo: 0.65%, W: 1.5%, and the balance is Fe and unavoidable impurities. The molten steel is then heated to 1680℃ and taken out of the furnace into the ladle. After all the molten steel enters the ladle, a wire feeder is used to send the multi-element alloy wire to the molten steel in the ladle. The amount of multi-element alloy wire added accounts for 4% of the mass fraction of the molten steel entering the ladle; the chemical composition and mass fraction of the multi-element alloy wire are 7.24% Ce, 15.43% Ti, 5.60% Ca, 5.61% K, 12.47% Si, and the remainder is Fe and inevitable impurities; after all the multi-element alloy wires are melted, the slag is removed and the molten steel is allowed to stand, and when the temperature of the molten steel drops to 1540°C, the molten steel is poured into the mold, and the molten steel solidifies in the mold and cools to when the surface temperature of the casting drops to 290°C, the casting is taken out of the mold, and then the casting is reheated to 950°C, kept warm for 2 hours, taken out of the furnace and air-cooled to a temperature of 270°C, kept warm for 4 hours, re-entered the furnace and heated to 380°C, kept warm for 4 hours, and then taken out of the furnace and air-cooled to room temperature, and the power hardware body can be obtained.

[0038] The power fitting body is subjected to quenching and partitioning treatment: first, the obtained power fitting body is heated in a muffle furnace at a heating rate of 10°C / min, a holding temperature of 1200°C, and a holding time of 240s, and then cooled to room temperature with the furnace. Finally, the power fitting body is heated in a muffle furnace at a heating rate of 10°C / min, a holding temperature of 380°C, and a holding time of 1 hour, and then cooled to room temperature with the furnace to obtain the power fitting.

[0039] Table 1 Comparison of wear amount of comparative quenching and partitioning electric hardware and example quenching and partitioning zincizing electric hardware (10N, 30 minutes)

[0040] Table 2 Comparison of corrosion resistance of quenched and partitioned electric power fittings in comparative example and quenched and partitioned zinc-plated electric power fittings in example

[0041] Table 3 Comparison of mechanical properties of comparative quenching and partitioning electric power fittings and example quenching and partitioning zincizing electric power fittings

[0042] As can be seen from Table 1, compared with single quenching and distribution electric hardware, the wear resistance of the quenching and distribution and zinc-infiltrated electric hardware prepared by the present invention is improved, and the wear amount is reduced under the same wear conditions. As can be seen from Table 2, compared with single quenching and distribution electric hardware, the corrosion current density of the quenching and distribution and zinc-infiltrated electric hardware prepared by the present invention is smaller and the corrosion voltage potential is higher, which indicates that its corrosion resistance is improved. As can be seen from Table 3, compared with single quenching and distribution electric hardware, the tensile strength, yield strength and elongation of the quenching and distribution and zinc-infiltrated electric hardware prepared by the present invention are improved. The above results show that compared with single quenching and distribution electric hardware, the quenching and distribution and zinc-infiltrated electric hardware prepared by the present invention has high strength and high plasticity, and the mechanical properties and elongation are improved at the same time, and the wear resistance and corrosion resistance are significantly improved. The improvement principle mainly lies in the following aspects: 1. Improving the mechanical properties and plastic properties of the steel material itself by reasonably designing the material composition; 2. Improving the mechanical properties and plastic properties by post-processing such as quenching and partitioning. Since the quenching and partitioning process can prepare a steel material with a mixed structure of ferrite, martensite and residual austenite, and martensite has higher strength, ferrite and residual austenite have higher plasticity, the mixed structure prepared by the quenching and partitioning process enables the steel to have good strength and plasticity at the same time; 3. In the present invention, in order to further improve the strength-plasticity matching of the steel material, that is, to have higher plasticity while improving the strength, quenching and partitioning and sherardizing are selected for coordinated treatment, and the strength and plasticity of the steel material are further improved under the synergistic effect of quenching and partitioning and sherardizing. Its mechanism of action is mainly to carry out the partitioning and the preparation of the zinc-diffusion layer simultaneously, which increases the partitioning time and greatly increases the ferrite content in the steel plate, thereby greatly increasing the elongation of the steel plate. At the same time, since the zinc and iron elements in the prepared zinc-diffusion layer can generate a series of Fe-Zn intermetallic compounds, the mechanical properties of the steel material can be improved, thereby improving the mechanical properties and plasticity of the steel material at the same time.

[0043] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. An electric power fitting, characterized in that: The electric power fitting comprises an electric power fitting body and a zinc-diffused layer on the surface of the electric power fitting body; The raw materials for preparing the power fitting body include steel and multi-element alloy, and the mass of the multi-element alloy is 2%-4% of the mass of the steel; The chemical composition of the steel includes, by mass fraction, C: 0.08% to 0.24%, Mn: 2.15% to 3.24%, Si: 1.40% to 1.60%, Al: ≤0.05%, Ti: 0.05% to 0.15%, P≤0.012%, S≤0.01%, Ni: 0.25% to 0.55%, Nb: 0.40% to 0.80%, Mo: 0.2% to 0.65%, W: 1% to 1.5%, and the balance is Fe and unavoidable impurities; The chemical composition of the multi-element alloy includes: Ce: 6.58%-7.24%, Ti: 15.32%-15.43%, Ca: 5.22%-5.60%, K: 5.52%-5.61%, Si: 10.53%-12.47%, and the balance is Fe and inevitable impurities.

2. The electric power fitting according to claim 1, characterized in that: Nb+Ni+Mo+W≤3.5%.

3. The electric power fitting according to claim 1, characterized in that: The raw material for preparing the sherardizing layer, the sherardizing agent, includes micron-sized zinc powder, Ce2O, activator NH4Cl and filler Al2O3, the activator NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, the filler Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is micron-sized zinc powder.

4. A method for preparing the electric power fittings according to any one of claims 1 to 3 by quenching and partitioning and sherardizing, characterized in that: include: Mixing scrap steel and steelmaking pig iron and heating them to melt, adding ferromanganese, ferrosilicon, ferroniobium, ferromolybdenum, ferrotungsten, ferronickel and ferrotitanium after the molten steel is completely melted, heating to a first preset temperature, then adding ferroaluminum, heating the molten steel to a second preset temperature, adding multi-element alloy, and after the multi-element alloy is completely melted, slagging and allowing the molten steel to stand; When the temperature of the molten steel drops to a third preset temperature, casting, solidification, and cooling are performed to obtain a casting; When the surface temperature of the casting drops to a fourth preset temperature, the casting is taken out, and repeatedly heated and kept warm, and then cooled to room temperature to obtain the power fitting body; A zinc infiltration layer is prepared on the electric power fitting body to obtain the electric power fitting.

5. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 4, characterized in that: The repeated heating and heat preservation are specifically: reheating the casting to a fifth preset temperature and keeping it warm for a first preset time, then cooling it to a sixth preset temperature, keeping it warm for a second preset time, reheating it to a seventh preset temperature, and keeping it warm for a third preset time.

6. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 5, characterized in that: The first preset temperature is 1540-1560°C; And / or, the second preset temperature is 1640-1680°C; And / or, the third preset temperature is 1500-1540° C.; And / or, the fourth preset temperature is 260-290°C And / or, the fifth preset temperature is 900-950° C.; And / or, the sixth preset temperature is 260-300° C.; And / or, the seventh preset temperature is 350-380°C.

7. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 4, characterized in that: The first preset time is 1-2 hours; And / or, the second preset time is 2-4 hours; And / or, the third preset time is 2-4 hours.

8. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 4, characterized in that: The preparation of the zincizing layer on the electric power fitting body is specifically as follows: The electric power fitting body is heated to a first insulation temperature and kept at the first insulation time, and then cooled to room temperature; The cooled electric power fitting body is mixed with the zincizing agent, and then heated to a second insulation temperature and maintained for a second time to obtain the electric power fitting.

9. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 8, characterized in that: The method of heating the electric power fitting body to a first insulation temperature and keeping it for a first time, and then cooling it to room temperature, specifically comprises heating the electric power fitting body to 880°C-1200°C at a heating rate of 4°C-10°C / min, keeping it for 30-240s, and then cooling it to room temperature.

10. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 8, characterized in that: The cooling of the electric power fitting body and the zincizing agent are mixed, and then heated to a second insulation temperature and kept for a second time to obtain the electric power fitting, specifically: The zincizing agent is mixed with the cooled electric power fittings, and the temperature is increased to 380°C-450°C at a heating rate of 4°C-10°C / min, and the temperature is kept for 1 hour-4 hours, and then cooled to room temperature to obtain the electric power fittings.

11. The method for preparing electric power fittings by quenching and partitioning and sherardizing according to claim 4, characterized in that: The sherardizing agent comprises micron-sized zinc powder, Ce2O, activator NH4Cl and filler Al2O3, wherein the activator NH4Cl accounts for 2%-6% of the total mass of the sherardizing agent, the filler Al2O3 accounts for 20%-30% of the total mass of the sherardizing agent, Ce2O accounts for 1%-3% of the total mass of the sherardizing agent, and the rest is micron-sized zinc powder.

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