High wear resistance high chromium cast iron material and its heat treatment process

Abstract

The application relates to the field of wear-resistant materials, and discloses a high-chromium cast iron material with high wear resistance and a heat treatment process of the high-chromium cast iron material. The heat treatment process steps are as follows: taking iron-coated zirconia toughened alumina ceramic as a reinforcing phase material; placing a casting in a heat treatment furnace, grading cooling to room temperature after heating in the furnace; then performing three-stage tempering to obtain a processed piece; performing surface cleaning and preheating on the cut processed piece to obtain a pretreated processed piece; uniformly mixing titanium-plated cubic boron nitride powder, graphite, nickel-based alloy powder and a binder, and prepositioning the mixture on the surface of the pretreated processed piece, and preparing a cladding layer by using laser cladding to obtain the high-chromium cast iron material with high wear resistance. The application takes the iron-coated zirconia toughened alumina ceramic as the reinforcing phase material, and prepares the cladding layer by using the titanium-plated cubic boron nitride powder, the graphite and the nickel-based alloy powder, and adopts the grading cooling and three-stage tempering mode to prepare the high-chromium cast iron material with high hardness, high impact toughness and high wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of wear-resistant materials, and in particular relates to a high-wear-resistant high-chromium cast iron material and a heat treatment process thereof. Background Art

[0002] High chromium cast iron is a widely used wear-resistant material with the advantages of high strength and good wear resistance. It is a white cast iron with a chromium content of 14-30%. The addition of a large amount of chromium makes the structure contain a certain amount of M7C3, M 23 C6 and M3C carbides, with their high hardness, are the hard phase in high-chromium cast iron, offering excellent wear resistance. M7C3 carbides, in particular, have a microhardness of 1300-1800 HV. Chromium rapidly forms a Cr2O3 oxide film at high temperatures, helping to prevent and delay oxidation. High-chromium cast iron, a superior abrasion-resistant material, is widely used in industries such as metallurgy, mining, construction, power generation, and machinery.

[0003] The microstructure of ordinary cast high-chromium cast iron contains a large number of sharp chrysanthemum-shaped carbides, which play a role in stress concentration, thereby reducing toughness and easily leading to premature fracture failure, which limits the use of high-chromium cast iron under high impact and high stress conditions. In addition, the heat treatment process of the prior art adopts quenching and high-temperature tempering or quenching and low-temperature tempering. Although the wear-resistant material obtained by quenching and high-temperature tempering has good impact toughness, it has low hardness and poor wear resistance and is easily deformed by impact. Although the hardness of the wear-resistant material obtained by quenching and low-temperature tempering is improved, its impact resistance is extremely poor. Moreover, as the service environment becomes increasingly harsh, traditional high-chromium cast iron cannot meet the needs of use. The prior art improves its performance by adding ceramic particles. Due to the large difference in thermal expansion coefficient between the high-chromium cast iron matrix and the ceramic particles, it is easy to cause problems such as cracks and ceramic particles falling off, thereby affecting its mechanical properties. Summary of the Invention

[0004] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a high-wear-resistant high-chromium cast iron material and its heat treatment process, using iron-coated zirconia toughened alumina ceramics as the reinforcing phase material, and using titanium-coated cubic boron nitride powder, graphite and nickel-based alloy powder to prepare the cladding layer, and adopting graded cooling and three-stage tempering to prepare a high-chromium cast iron material with high hardness, high impact toughness and high wear resistance.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A heat treatment process for a high-wear-resistant high-chromium cast iron material comprises the following steps:

[0007] A, the castings are placed in a heat treatment furnace, the temperature in the furnace is first raised to 850~900℃, after 5~10min of heat preservation, the temperature is raised to 970~1100℃ at a rate of 30~40℃ / min, after 20~30min of heat preservation, the temperature is gradually cooled to room temperature;

[0008] B, the quenched castings are tempered by using a muffle furnace, the first tempering temperature is 350~400℃, the heat preservation time is 10~12h, the second tempering temperature is 300~320℃, the heat preservation time is 12~15h, the third tempering temperature is 280~300℃, the heat preservation time is 17~20h, and the processed parts are obtained;

[0009] C, the processed parts are cut into the required size by using wire cutting, the surface is polished by using a grinding machine and sandpaper in turn, then the processed parts are cleaned by using alcohol and dried by blowing, the processed parts are preheated at 275~350℃, and the pretreated processed parts are obtained;

[0010] D, titanium-plated cubic boron nitride powder, graphite and nickel-based alloy powder are uniformly mixed, dried in a drying box to remove water, and pre-applied on the surface of the pretreated processed parts by using a binder, then a cladding layer is prepared by using laser cladding under the protection of argon, and the high-chromium cast iron material with high wear resistance is obtained.

[0011] Preferably, the specific steps of the step A of gradual cooling are as follows: first cooled to 940~1070℃ and heat preserved for 20~30min, then cooled to 710~840℃ at a cooling rate of 10~12℃ / s, then cooled to 620~750℃ at a cooling rate of 18~22℃ / s, then cooled to 500~560℃ at a cooling rate of 11~13℃ / s, heat preserved for 30~60min, and finally cooled to room temperature at a cooling rate of 280~305℃ / min.

[0012] Preferably, the preparation method of the castings in the step A comprises the following steps:

[0013] A1, the raw materials are weighed according to the mass percentage content of each alloying element: C: 3.2~3.6%, Cr: 24~27%, Mn: 0.6~1.2%, Cu: 0.4~0.6%, Si≤1.00%, S≤0.06%, P≤0.06%, and the balance is Fe, the raw materials are placed in an induction furnace and heated to melt, impurities are removed, and the iron liquid is obtained;

[0014] A2, the zirconia toughened alumina ceramic is placed in a quartz boat, covered with dry anhydrous ferrous chloride, and then placed at the bottom of the quartz tube, argon gas is used as the protective gas, and the iron coating is deposited on the surface of the zirconia toughened alumina ceramic by using chemical vapor deposition method, and the iron-deposited zirconia toughened alumina ceramic is obtained;

[0015] A3, the iron-deposited zirconia toughened alumina ceramic is embedded into plastic foam, and the iron liquid is used for casting by using the lost foam casting method, and the temperature is set to 1600-1780 DEG C, and the casting is obtained.

[0016] Preferably, the chemical vapor deposition process conditions in the step A2 are as follows: the deposition temperature is 620-700 DEG C, the temperature rising rate is 3-6 DEG C / min, the hydrogen is introduced after the temperature rises to 620-700 DEG C, and the hydrogen flow is 190-210 mL / min.

[0017] Preferably, the preparation method of the titanium-plated cubic boron nitride in the step D comprises the following steps: cubic boron nitride, titanium trichloride and titanium hydride powder are put into a plating container, the plating temperature is set to 760-795 DEG C, the vacuum degree is 0.01-0.05 Pa, the temperature is kept for 10-20 min, the vacuum degree is kept at 0.01-0.05 Pa, and the furnace is cooled to room temperature, and the titanium-plated cubic boron nitride is prepared.

[0018] Preferably, the mass ratio of the cubic boron nitride, titanium trichloride and titanium hydride powder is 97-105:1.5-3:14.5-17.

[0019] Preferably, the mass ratio of the titanium-plated cubic boron nitride powder, graphite and nickel-based alloy powder in the step D is 2.7-5.5:1:2.4-3.5.

[0020] Preferably, the nickel-based alloy powder in the step D is Ni60 self-fluxing powder, the mass fraction of each chemical component is 15.5%Cr, 3.5%B, 4.0%Si, 0.8%C, 15.0%Fe, 3.0%W, and the rest is Ni; and the binder is sodium water glass.

[0021] Preferably, the laser cladding process conditions in the step D are as follows: the laser power is 2.2-2.5 kW, and the laser scanning speed is 240-260 mm / min.

[0022] A high-chromium cast iron material with high wear resistance is obtained after being treated by the heat treatment process.

[0023] The beneficial effects of the application are as follows:

[0024] The application utilizes the chemical vapor deposition method to deposit a uniform, continuous and dense iron coating on the surface of the zirconia toughened alumina ceramic, and utilizes the iron liquid to cast the casting by the lost foam casting method, which is beneficial to improve the interface bonding performance of the high chromium cast iron and the zirconia toughened alumina ceramic, and further improve the impact toughness of the high chromium cast iron material, then the casting is placed in a heat treatment furnace, and after heating, the casting is quenched by a staged cooling method, and then is tempered by three stages, to obtain a processed piece, which is helpful to improve the toughness and impact resistance of the processed piece, and is also beneficial to reduce the internal and external temperature difference and thermal stress of the processed piece in the cooling process, and reduce the cracking risk of the processed piece, then the surface of the processed piece is cleaned and preheated, and a cladding layer is prepared on the pretreated processed piece surface by laser cladding, the cladding layer utilizes titanium-plated cubic boron nitride powder, graphite, nickel-based alloy powder and a binder as raw materials, and adopts vacuum micro-evaporation plating technology, wherein the titanium-plated cubic boron nitride uses cubic boron nitride, titanium trichloride and titanium hydride powder as raw materials, titanium trichloride and titanium hydride react to form titanium atoms under vacuum heating conditions, and deposit on the surface of the cubic boron nitride to form titanium carbide, which improves the hardness, impact toughness and high-temperature resistance of the high chromium cast iron material, in addition, the titanium-plated cubic boron nitride has high hardness and good lubricity, and the added titanium-plated cubic boron nitride powder and graphite can improve the wear resistance of the high chromium cast iron material in terms of wear resistance and wear reduction, and a high-hardness and low-friction wear-resistant cladding layer is prepared, in addition, the heat treatment method is used to improve the microstructure of the substrate and the hardness of the substrate, to avoid the problem of cracking at the interface between the high chromium cast iron and the zirconia toughened alumina ceramic, and to improve the mechanical properties of the high chromium cast iron material. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0026] The preparation method of the casting in Embodiment 1 comprises the following steps:

[0027] A1, the raw materials are weighed according to the mass percentage content of each alloying element: C: 3.4%, Cr: 25%, Mn: 0.9%, Cu: 0.5%, Si≤1.00%, S≤0.06%, P≤0.06%, and the balance is Fe, which is placed in an induction furnace and heated to melt all the raw materials, and impurities are removed to obtain an iron liquid;

[0028] A2, the zirconia toughened alumina ceramic is placed in a quartz boat, covered with dry anhydrous ferrous chloride, and then placed at the bottom of a quartz tube, argon gas is used as a protective gas, and a chemical vapor deposition method is used to deposit an iron coating on the surface of the zirconia toughened alumina ceramic, the deposition temperature is 660℃, the heating rate is 5℃ / min, hydrogen gas is introduced after the temperature rises to 660℃, the hydrogen gas flow is 205mL / min, and the temperature is kept for 1h to obtain the iron-deposited zirconia toughened alumina ceramic;

[0029] A3, the iron-deposited zirconia toughened alumina ceramic is embedded in a plastic foam, and a lost foam casting method is used to cast with iron liquid, the temperature is set to 1680℃, and the casting is obtained.

[0030] The preparation method of the titanium-plated cubic boron nitride includes the following steps:

[0031] The cubic boron nitride, titanium trichloride and titanium hydride powder are placed in a plating container at a mass ratio of 100:1.7:15, the plating temperature is set to 780℃, the vacuum degree is 0.01Pa, the temperature is kept for 15min, the vacuum degree is maintained at 0.01Pa, and the furnace is cooled to room temperature, thereby obtaining the titanium-plated cubic boron nitride.

[0032] The heat treatment process of the high-chromium cast iron material with high wear resistance includes the following steps:

[0033] A, the casting prepared in Example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, and then heated to 970℃ at a heating rate of 30℃ / min, and then cooled to 940℃ and kept for 30min, and then cooled to 710℃ at a cooling rate of 10℃ / s, and then cooled to 620℃ at a cooling rate of 18℃ / s, and then cooled to 500℃ at a cooling rate of 11.5℃ / s, and then kept for 40min, and finally cooled to room temperature at a cooling rate of 280℃ / min;

[0034] B, the quenched casting is tempered in a muffle furnace, the first tempering temperature is 350℃, the second tempering temperature is 300℃, the third tempering temperature is 280℃, and the tempering time is 12h, 15h and 20h respectively, and the processed part is obtained;

[0035] C, the processed part is cut into the required size by wire cutting, the surface is polished in turn using a grinding machine and sandpaper, and then cleaned with alcohol and blown dry, preheated at 285℃, and the pretreated processed part is obtained;

[0036] D, take the titanium plated cubic boron nitride powder prepared in example 2, graphite and Ni60 self fluxing powder are mixed uniformly according to the mass ratio of 3.2:1:2.5, placed in a drying oven to dry and remove water, and prepositioned on the surface of the pretreated workpiece with a binder sodium water glass, then under the protection of argon, a cladding layer is prepared by laser cladding, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high wear resistance high chromium cast iron material.

[0037] Example 4 A heat treatment process of a high wear resistance high chromium cast iron material, comprising the following steps:

[0038] A, the castings prepared in example 1 are placed in a heat treatment furnace, the temperature in the furnace is first raised to 875℃, and then heated to 1000℃ at a heating rate of 32℃ / min, and then cooled to 960℃ and kept for 30min, and then cooled to 730℃ at a cooling rate of 11.5℃ / s, and then cooled to 650℃ at a cooling rate of 20℃ / s, and then cooled to 520℃ at a cooling rate of 12℃ / s, and then kept for 60min, and finally cooled to room temperature at a cooling rate of 290℃ / min;

[0039] B, the quenched castings are tempered in a muffle furnace, the first tempering temperature is 400℃, the second tempering temperature is 320℃, the third tempering temperature is 300℃, and the tempering time is 12h, 14h and 20h respectively, to obtain a workpiece;

[0040] C, the workpiece is cut into the required size by wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then washed with alcohol and blown dry, preheated at 300℃, to obtain a pretreated workpiece;

[0041] D, take the titanium plated cubic boron nitride powder prepared in example 2, graphite and Ni60 self fluxing powder are mixed uniformly according to the mass ratio of 3.2:1:2.5, placed in a drying oven to dry and remove water, and prepositioned on the surface of the pretreated workpiece with a binder sodium water glass, then under the protection of argon, a cladding layer is prepared by laser cladding, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high wear resistance high chromium cast iron material.

[0042] Example 5 A heat treatment process of a high wear resistance high chromium cast iron material, comprising the following steps:

[0043] A, the cast prepared in example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 900 DEG C, after 10 min, heated to 1100 DEG C at a rate of 40 DEG C / min, after 20 min, first cooled to 1070 DEG C and kept for 30 min, after the end of the holding, cooled to 840 DEG C at a cooling rate of 12 DEG C / s, then cooled to 750 DEG C at a cooling rate of 20.5 DEG C / s, then cooled to 560 DEG C at a cooling rate of 13 DEG C / s, kept for 30 min, finally cooled to room temperature at a cooling rate of 302 DEG C / min;

[0044] B, the quenched cast is tempered by using a muffle furnace, the first tempering temperature is 370 DEG C, kept for 10 h, the second tempering temperature is 305 DEG C, kept for 14 h, the third tempering temperature is 285 DEG C, kept for 18 h, to obtain a processed piece;

[0045] C, the processed piece is cut into the required size by using wire cutting, the surface is polished in turn by using a grinding machine and sandpaper, then cleaned with alcohol and dried, preheated at 285 DEG C, to obtain a pretreated processed piece;

[0046] D, the titanium-plated cubic boron nitride powder prepared in example 2, graphite and Ni60 self-fluxing powder are mixed uniformly according to the mass ratio of 2.7:1:2.4, dried in a drying box to remove water, and pre-applied on the surface of the pretreated processed piece by using a binder sodium water glass, then a cladding layer is prepared by using laser cladding under the protection of argon, the laser power is 2.4 kW, and the laser scanning speed is 250 mm / min, to obtain a high-chromium cast iron material with high wear resistance.

[0047] Preparation method of a cast in comparative example 1 includes the following steps:

[0048] A1, the raw materials are weighed according to the mass percentage content of each alloying element: C: 3.4%, Cr: 25%, Mn: 0.9%, Cu: 0.5%, Si≤1.00%, S≤0.06%, P≤0.06%, and the balance is Fe, which is placed in an induction furnace and heated to melt all the raw materials, and impurities are removed to obtain an iron liquid;

[0049] A2, the zirconia toughened alumina ceramic is embedded in the plastic foam, and the lost foam casting method is used to cast the iron liquid at a temperature of 1680 DEG C to obtain a cast.

[0050] Heat treatment process of a high-chromium cast iron material with high wear resistance in comparative example 2 includes the following steps:

[0051] A, the cast prepared in Example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, after 5min of holding, heated to 970℃ at a rate of 30℃ / min, after 20min of holding, first cooled to 940℃ and held for 30min, after the holding is over, cooled to 710℃ at a rate of 10℃ / s, then cooled to 620℃ at a rate of 18℃ / s, then cooled to 500℃ at a rate of 11.5℃ / s, held for 40min, and finally cooled to room temperature at a rate of 280℃ / min;

[0052] B, the quenched cast is tempered using a muffle furnace, the first tempering temperature is 350℃, holding for 12h, and the second tempering temperature is 300℃, holding for 15h, to obtain a processed piece;

[0053] C, the processed piece is cut into a desired size using wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then cleaned using alcohol and dried, preheated at 285℃, to obtain a pretreated processed piece;

[0054] D, the titanium-plated cubic boron nitride powder prepared in Example 2, graphite and Ni60 self-fluxing powder are mixed uniformly at a mass ratio of 3.2:1:2.5, dried in a drying box to remove water, and pre-applied on the surface of the pretreated processed piece using a binder sodium water glass, then a cladding layer is prepared using laser cladding under argon protection, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high-chromium cast iron material with high wear resistance.

[0055] Comparative Example 3 A heat treatment process of a high-chromium cast iron material with high wear resistance, comprising the following steps:

[0056] A, the cast prepared in Example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, after 5min of holding, heated to 970℃ at a rate of 30℃ / min, after 20min of holding, first cooled to 940℃ and held for 30min, after the holding is over, cooled to 710℃ at a rate of 10℃ / s, then cooled to 620℃ at a rate of 18℃ / s, then cooled to 500℃ at a rate of 11.5℃ / s, held for 40min, and finally cooled to room temperature at a rate of 280℃ / min;

[0057] B, the quenched cast is tempered using a muffle furnace, the first tempering temperature is 350℃, holding for 12h, and the second tempering temperature is 300℃, holding for 15h, to obtain a processed piece;

[0058] C, the processed piece is cut into a desired size using wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then cleaned using alcohol and dried, preheated at 285℃, to obtain a pretreated processed piece;

[0059] D, take the titanium plated cubic boron nitride powder prepared in example 2, graphite and Ni60 self fluxing powder are mixed uniformly according to the mass ratio of 3.2:1:2.5, placed in a drying oven to dry and remove water, and prepositioned on the surface of the pretreated workpiece with a binder sodium water glass, then under the protection of argon, a cladding layer is prepared by laser cladding, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high wear resistance high chromium cast iron material.

[0060] Comparative example 4, a heat treatment process of a high wear resistance high chromium cast iron material, comprising the following steps:

[0061] A, the castings prepared in comparative example 1 are placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, then heated to 970℃ at a heating rate of 30℃ / min, and then cooled to 940℃ and kept for 30min, then cooled to 710℃ at a cooling rate of 10℃ / s, then cooled to 620℃ at a cooling rate of 18℃ / s, then cooled to 500℃ at a cooling rate of 11.5℃ / s, kept for 40min, and finally cooled to room temperature at a cooling rate of 280℃ / min;

[0062] B, the quenched castings are tempered in a muffle furnace, the first tempering temperature is 350℃, the second tempering temperature is 300℃, the third tempering temperature is 280℃, and the tempering time is 12h, 15h and 20h respectively, to obtain a workpiece;

[0063] C, the workpiece is cut into the required size by wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then cleaned with alcohol and blown dry, preheated at 285℃, to obtain a pretreated workpiece;

[0064] D, take the titanium plated cubic boron nitride powder prepared in example 2, graphite and Ni60 self fluxing powder are mixed uniformly according to the mass ratio of 3.2:1:2.5, placed in a drying oven to dry and remove water, and prepositioned on the surface of the pretreated workpiece with a binder sodium water glass, then under the protection of argon, a cladding layer is prepared by laser cladding, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high wear resistance high chromium cast iron material.

[0065] Comparative example 5, a heat treatment process of a high wear resistance high chromium cast iron material, comprising the following steps:

[0066] A, the cast prepared in Example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, after 5min of holding, heated to 970℃ at a rate of 30℃ / min, after 20min of holding, first cooled to 940℃ and held for 30min, after the holding is over, cooled to 710℃ at a rate of 10℃ / s, then cooled to 620℃ at a rate of 18℃ / s, then cooled to 500℃ at a rate of 11.5℃ / s, held for 40min, and finally cooled to room temperature at a rate of 280℃ / min;

[0067] B, the quenched cast is tempered using a muffle furnace, the first tempering temperature is 350℃, holding for 12h, the second tempering temperature is 300℃, holding for 15h, the third tempering temperature is 280℃, holding for 20h, to obtain a processed piece;

[0068] C, the processed piece is cut into the required size using wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then cleaned using alcohol and dried, preheated at 285℃, to obtain a pretreated processed piece;

[0069] D, the titanium-plated cubic boron nitride powder prepared in Example 2 and the Ni60 self-fluxing powder are mixed uniformly at a mass ratio of 3.2:2.5, placed in a drying box to dry and remove water, and pre-applied to the surface of the pretreated processed piece using a binder sodium water glass, then a cladding layer is prepared using laser cladding under argon protection, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high-chromium cast iron material with high wear resistance.

[0070] The heat treatment process of a high-chromium cast iron material with high wear resistance of Comparative Example 6 comprises the following steps:

[0071] A, the cast prepared in Example 1 is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850℃, after 5min of holding, heated to 970℃ at a rate of 30℃ / min, after 20min of holding, first cooled to 940℃ and held for 30min, after the holding is over, cooled to 710℃ at a rate of 10℃ / s, then cooled to 620℃ at a rate of 18℃ / s, then cooled to 500℃ at a rate of 11.5℃ / s, held for 40min, and finally cooled to room temperature at a rate of 280℃ / min;

[0072] B, the quenched cast is tempered using a muffle furnace, the first tempering temperature is 350℃, holding for 12h, the second tempering temperature is 300℃, holding for 15h, the third tempering temperature is 280℃, holding for 20h, to obtain a processed piece;

[0073] C, the workpiece is cut into the required size by wire cutting, the surface is polished in turn using a grinding machine and sandpaper, then cleaned with alcohol and dried, and preheated at 285℃ to obtain a pretreated workpiece;

[0074] D, cubic boron nitride powder, graphite and Ni60 self-fluxing powder are mixed uniformly in a mass ratio of 3.2:1:2.5, dried in a drying box to remove water, and pre-applied on the surface of the pretreated workpiece with a binder sodium water glass, then a cladding layer is prepared by laser cladding under argon protection, the laser power is 2.4kW, and the laser scanning speed is 250mm / min, to obtain a high-chromium cast iron material with high wear resistance.

[0075] Performance detection

[0076] The high-chromium cast iron materials prepared in Examples 3-5 and Comparative Examples 2-6 are subjected to performance detection: the tensile strength and bending strength of the materials are tested by a universal testing machine, the impact toughness and hardness of the samples are tested by a pendulum impact testing machine and a Rockwell hardness tester, each group of samples is tested 3 times, and the average value is taken; the wear resistance test is performed by a multifunctional friction and wear testing machine, using a linear reciprocating wear method, using Si3N4 balls as the grinding ball with a diameter of 4.7mm, a load of 50N, a time of 40min, and a frequency of 2HZ, and the data results are shown in Table 1.

[0077] Table 1: Performance detection results of samples

[0078]

[0079] As can be seen from the data in Table 1, the high-chromium cast iron material prepared in Examples 3-5 has excellent mechanical properties, high tensile strength, bending strength, impact toughness and hardness, and small wear volume. In Comparative Example 2, only one-stage tempering is performed, in Comparative Example 3, only two-stage tempering is performed, in Comparative Example 4, zirconia toughened alumina ceramic is added to the castings, in Comparative Example 5, no graphite is added, and in Comparative Example 6, uncoated cubic boron nitride is added. The mechanical properties of the high-chromium cast iron materials prepared in Comparative Examples 2-6 are lower than those of Examples 3-5 to different degrees, and the wear resistance of Comparative Examples 5-6 is significantly lower than that of Examples 3-5, indicating that the addition of graphite and titanium-coated cubic boron nitride can further improve the wear resistance of the high-chromium cast iron material.

[0080] In the description of the specification, the description of the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate way in one or more embodiments or examples.

[0081] The basic principles, main features and advantages of the present application are shown and described above. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A heat treatment process of a high abrasion resistant high chromium cast iron material, characterized by, It comprises the following steps: A, the cast is placed in a heat treatment furnace, the temperature in the furnace is first raised to 850~900℃, after 5~10min of heat preservation, it is heated to 970~1100℃ at a heating rate of 30~40℃ / min, after 20~30min of heat preservation, it is gradually cooled to room temperature; B, the quenched cast is tempered by using a muffle furnace, the first tempering temperature is 350~400℃, the heat preservation time is 10~12h, the second tempering temperature is 300~320℃, the heat preservation time is 12~15h, the third tempering temperature is 280~300℃, the heat preservation time is 17~20h, and the processed piece is obtained; C, the processed piece is cut into the required size by using wire cutting, the surface is polished in turn by using a grinding machine and sandpaper, then it is cleaned by using alcohol and dried by blowing, and is preheated at 275~350℃ to obtain a pretreated processed piece; D, titanium-plated cubic boron nitride powder, graphite and nickel-based alloy powder are uniformly mixed, dried in a drying box to remove water, and prepositioned on the surface of the pretreated processed piece, then a cladding layer is prepared by using laser cladding under the protection of argon to obtain a high-chromium cast iron material with high wear resistance; The preparation method of the cast in step A comprises the following steps: A1, the raw materials are weighed according to the mass percentage content of each alloying element: C: 3.2~3.6%, Cr: 24~27%, Mn: 0.6~1.2%, Cu: 0.4~0.6%, Si≤1.00%, S≤0.06%, P≤0.06%, and the balance is Fe, which is placed in an induction furnace and heated to melt all the raw materials to remove impurities to obtain iron liquid; A2, zirconia toughened alumina ceramic is placed in a quartz boat, covered with dry anhydrous ferrous chloride, and then placed at the bottom of the quartz tube, argon is used as protective gas, and iron coating is deposited on the surface of the zirconia toughened alumina ceramic by using chemical vapor deposition method to obtain iron-deposited zirconia toughened alumina ceramic; A3, the iron-deposited zirconia toughened alumina ceramic is embedded in plastic foam, and is cast by using iron liquid by using lost foam casting method, and the temperature is set to 1600~1780℃ to obtain the cast.

2. The heat treatment process of high chromium cast iron material of high wear resistance according to claim 1, characterized in that, The specific steps of the step A of gradual cooling are: first cooling to 940~1070℃ and heat preservation for 20~30min, after the heat preservation is completed, cooling to 710~840℃ at a cooling rate of 10~12℃ / s, then cooling to 620~750℃ at a cooling rate of 18~22℃ / s, then cooling to 500~560℃ at a cooling rate of 11~13℃ / s, heat preservation for 30~60min, and finally cooling to room temperature at a cooling rate of 280~305℃ / min.

3. The heat treatment process of high chromium cast iron material of high wear resistance as claimed in claim 1, wherein, The process conditions of the chemical vapor deposition in step A2 are: deposition temperature 620~700℃, heating rate 3~6℃ / min, hydrogen is introduced after the temperature rises to 620~700℃, and the hydrogen flow rate is 190~210mL / min.

4. The heat treatment process of high chromium cast iron material of high wear resistance according to claim 1, characterized in that, The preparation method of the titanium-plated cubic boron nitride in step D comprises the following steps: cubic boron nitride, titanium trichloride and titanium hydride powder are put into a plating container, the plating temperature is set to 760-795 DEG C, the vacuum degree is 0.01-0.05 Pa, the temperature is kept for 10-20 min, the vacuum degree is kept at 0.01-0.05 Pa, and the furnace is cooled to room temperature, thereby obtaining the titanium-plated cubic boron nitride.

5. The heat treatment process of high chromium cast iron material of high wear resistance according to claim 4, characterized in that, The mass ratio of the cubic boron nitride, titanium trichloride and titanium hydride powder is 97-105:1.5-3:14.5-17.

6. The heat treatment process of high chrome cast iron material of high wear resistance as claimed in claim 1, wherein, The mass ratio of the titanium-plated cubic boron nitride powder, graphite and nickel-based alloy powder in step D is 2.7-5.5:1:2.4-3.

5.

7. The heat treatment process of high chrome cast iron material of high wear resistance as claimed in claim 1, wherein, The nickel-based alloy powder in step D is Ni60 self-fluxing powder, and the mass fraction of each chemical component is 15.5% Cr, 3.5% B, 4.0% Si, 0.8% C, 15.0% Fe, 3.0% W, and the rest is Ni; the binder is sodium water glass.

8. The heat treatment process of high chrome cast iron material of high wear resistance as claimed in claim 1, wherein, The laser cladding process condition in step D is: laser power 2.2-2.5 kW, and laser scanning speed 240-260 mm / min.

9. A high abrasion resistant high chromium cast iron material, characterized by, After being treated by the heat treatment process in any one of claims 1-8. After being treated by the heat treatment process in any one of claims 1-8.

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