CN115846624B - Preparation method of ceramic/iron-based honeycomb structural composite material - Google Patents

Abstract

The invention discloses a preparation method of a ceramic/iron-based honeycomb structural composite material, and belongs to the technical field of metal matrix composite materials. The method comprises the steps of uniformly mixing sol prepared from ferric nitrate nonahydrate, citric acid and the like with sol prepared from hydrated titanium dioxide, active carbon and the like, drying, calcining at high temperature, roasting, reducing and the like to obtain mixed powder of titanium carbonitride ceramic and iron, uniformly stirring the mixed powder and a binder, filling the mixed powder into honeycomb walls of a honeycomb structure die, curing to form a preform, and casting a steel melt to obtain the titanium carbonitride ceramic reinforced iron-based honeycomb structure composite material. The titanium carbonitride ceramic is uniformly dispersed in the iron matrix of the composite region, the honeycomb wall of the configuration composite material is composed of the composite region with higher hardness, the abrasion action of the honeycomb holes with softer hardness can be obviously reduced, the abrasion resistance is improved by more than 4 times compared with that of the traditional iron and steel materials, and the titanium carbonitride ceramic has wide application prospect in the fields of metallurgy, mines, building materials and the like.

Description

A kind of preparation method of ceramic/iron-based honeycomb structure composite material

technical field

The invention relates to a preparation method of a ceramic/iron-based honeycomb structure composite material, belonging to the technical field of metal-based composite materials.

Background technique

In mining, metallurgy, building materials and other fields, wear parts such as blow bars, hammer heads, and grinding rollers require materials with high mechanical and abrasive wear resistance. Ceramic/steel-based honeycomb composite materials have the advantages of high designability, good wear resistance, and low cost, and have become an important development direction of wear-resistant materials for equipment manufacturing.

In the common ceramic phase of ceramic/iron-based composite materials, titanium carbonitride (Ti(C,N)), titanium carbide (TiC), tungsten carbide (WC) and other carbides and aluminum oxide (Al ₂ O ₃ ), oxide Oxides such as zirconium toughened alumina (ZTA) have good mechanical and wear resistance properties, and scholars at home and abroad have done a lot of research and application work on these composite materials, among which titanium carbonitride (Ti(C,N )) Ceramics have good toughness and low cost, and are widely used in wear-resistant parts. However, when the wear-resistant parts are in service, they use extrusion to crush and grind the materials, and it is necessary for the reinforced phase of the composite material not to break and fall off under strong pressure. The reduction of ceramic particle size can significantly reduce the brittleness of large-sized particles, and the interface bonding strength between self-generated ceramic particles and iron matrix is also high. Workers' attention, but no breakthroughs have been made. In addition, in the preparation process of traditional ceramic-reinforced iron-based surface composite materials, the impregnation depth of the iron matrix to the ceramics is insufficient, and the thickness of the composite layer is thin, and due to the large difference in thermal physical parameters between the composite area and the matrix area, the composite layer is in use. Easy to peel off the whole layer.

Only the Chinese invention patent CN202210462248.4 discloses the preparation method of titanium carbonitride and chromium carbide synergistically reinforced iron-based composite impeller, that is, the reinforcement particles and EPS beads are weighed according to the volume fraction, and the organic binder and the EPS beads are first mixed. Mix, and then add the mixed reinforcement and mix to obtain the loose material with the mixed reinforcement bonded to the surface of the EPS beads and add it to the delivery pipe, and use the V-EPC lost foam casting process to prepare the impeller. In the iron-based composite material prepared by this method, the ceramic phase is compounded in the form of external addition, which does not solve the problem of intrinsic brittleness of the ceramic, and because the density difference between the ceramic reinforcement and the polymer EPS beads is too large, it is difficult for the two Evenly dispersed, prone to agglomeration and segregation.

Contents of the invention

In order to solve the problems of intrinsic brittleness of ceramic reinforced iron-based composite materials with large size ceramic phases, agglomeration and segregation of ceramic reinforcements, easy peeling of the entire layer of the composite area of the surface composite material during service, and insufficient wear resistance, the present invention combines iron precursors and The precursors of titanium carbonitride are uniformly mixed, and a new method for preparing a honeycomb composite material with ceramic reinforcement uniformly dispersed in the composite area is obtained, which specifically includes the following steps:

(1) Dissolve ferric nitrate nonahydrate in citric acid solution, and control the ratio of ferric nitrate nonahydrate and citric acid in the solution, and then put the mixed solution in a water bath for constant temperature heating to obtain sol ①.

(2) Add nano-activated carbon into the hydrated titanium dioxide solution, and after high-speed stirring, put the mixed solution into a water bath for constant temperature heating to obtain a sol②.

(3) Mix the sol ① obtained in step (1) with the sol ② obtained in step (2) in proportion and evenly, and obtain a mixed gel after vacuum drying.

(4) The mixed gel obtained in step (3) is calcined at a high temperature in nitrogen, and then calcined to obtain a mixed powder of titanium carbonitride and iron oxide, which is then placed in a reduction furnace and reduced by a reducing gas to obtain Mixed powder of titanium carbonitride and iron;

(5) Stir the mixed powder and binder obtained in step (4) evenly and put them into the honeycomb wall of the honeycomb structure mold to solidify to form a prefabricated body. After pouring the steel melt, titanium carbonitride ceramic reinforced iron matrix can be obtained. Honeycomb composites.

Preferably, the molar ratio of ferric nitrate and citric acid in step (1) of the present invention is 1:(0.6~1.2).

Preferably, the heating condition of the water bath in step (1) of the present invention is: 60-90°C, heating for 8-12h.

Preferably, the molar ratio of the hydrated titanium dioxide to the nano activated carbon in step (2) of the present invention is 1:(0.8~1.2), and the particle size of the nano activated carbon is 10-30nm.

Preferably, the heating condition of the water bath in step (2) of the present invention is: 40-70°C, heating for 4-8h.

Preferably, the molar ratio of Fe ions in sol ① in step (3) of the present invention to Ti ions in sol ② is 1:(0.02~0.4).

Preferably, the drying condition in step (3) of the present invention is: drying in a vacuum oven at 100-150° C. for 14-20 hours.

Preferably, the calcination and roasting conditions in step (4) of the present invention are: calcining at 1400-1600° C. for 2-4 hours under nitrogen atmosphere, and 3-5 hours of calcination at 800-1000° C. under air atmosphere.

Preferably, the reduction gas used in the reduction process in step (5) of the present invention is hydrogen, the temperature of the reduction furnace is 600-800°C, the flow rate of hydrogen is 1.0-2.0m ³ /h, and the time is 4-6h.

Preferably, the binder in step (5) of the present invention is any one of polyvinyl alcohol, ethylene-vinyl acetate copolymer, and starch paste.

Preferably, the molar ratio of the binder to the mixed powder of titanium carbonitride and iron in step (5) of the present invention is (0.02-0.04):1.

Preferably, the curing condition in step (5) of the present invention is: curing in an incubator at 90-130° C. for 6-10 hours.

The steel melt in the present invention is conventional steel, preferably any one of high chromium cast iron, high manganese steel and alloy steel.

The beneficial effect of the present invention compared with prior art is:

1) In the present invention, the precursor sol of iron and the precursor sol of titanium carbonitride are uniformly mixed in the liquid form in the early stage of composite material preparation, which avoids the occurrence of excessive density difference when the external ceramic reinforcement is mixed with iron or EPS The problem of agglomeration or segregation of reinforcements; 2) In the method of the present invention, titanium carbonitride ceramics are in situ self-generated, and the size of ceramic reinforcements is nanoscale, which significantly reduces the intrinsic brittleness of ceramics, and because ceramic reinforcements are in Nucleation and growth in the iron matrix, so there is no pollution on the surface of the reinforcement, and the compatibility between the matrix and the reinforcement is good; 3) The honeycomb wall of the honeycomb composite material in the present invention is made of ceramic + iron with high hardness Composed of a composite zone, the honeycomb hole is composed of a steel metal zone with a lower hardness. During the wear process, the composite zone with a higher hardness can prevent the wear of the metal zone with a lower hardness, and the composite layer is not easy to peel off, and the wear resistance is relatively high. The traditional surface composite material is more than 2 times higher than that of traditional steel materials, which is more than 4 times higher.

Description of drawings

Fig. 1 is the solidified honeycomb preform photo prepared by the present invention;

Fig. 2 is the surface morphology of the titanium carbonitride/iron-based honeycomb structure composite material prepared in the present invention.

Detailed ways

The technical solutions in the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the present invention Embodiments, and all other embodiments obtained by persons of ordinary skill in the art without creative efforts, all belong to the scope of protection of the present invention.

Example 1

This embodiment relates to a method for preparing a ceramic/high-chromium cast iron-based honeycomb composite material, and the specific steps are as follows:

(1) Dissolve ferric nitrate nonahydrate in citric acid solution, and control the molar ratio of ferric nitrate nonahydrate and citric acid in the solution to 1:1, then put the mixed solution in a water bath, and heat it at a constant temperature at 80°C 10h, the sol ① was obtained.

(2) Add activated carbon with a particle size of 20nm to the hydrated titanium dioxide solution, wherein the molar ratio of hydrated titanium dioxide and nano-activated carbon is 1:1. After high-speed stirring, put the mixed solution into a water bath and heat at 60°C for 5 hours. Sol ② was obtained.

(3) Mix the sol ① obtained in step (1) with the sol ② obtained in step (2) according to the molar ratio of Fe ions and Ti ions at a ratio of 1:0.2, and then put the mixture into a vacuum drying oven at 105 It was dried at ℃ for 16h to obtain a mixed gel.

(4) The mixed gel obtained in step (3) was calcined in a nitrogen atmosphere at 1500°C for 2.5h, and then calcined in an air atmosphere at 900°C for 4.5h to obtain a mixed powder of titanium carbonitride and iron oxide.

(5) Put the mixed powder into the hydrogen reduction furnace, the temperature of the hydrogen reduction furnace is 750°C, the hydrogen flow rate is 1.2m ³ /h, and the time is 5h, to obtain the mixed powder of titanium carbonitride and iron.

(6) Mix the mixed powder with polyvinyl alcohol binder evenly. The molar ratio of polyvinyl alcohol and mixed powder is 0.02:1. After curing at 120°C for 8 hours, a honeycomb-shaped preform is formed. The macroscopic photo of the preform is as follows: As shown in Figure 1, it can be seen from Figure 1 that the titanium carbonitride and iron in the preform are evenly mixed.

(7) Put the prefabricated body into the pouring cavity, then pour the smelted high-chromium cast iron melt into it, and after cooling, titanium carbonitride ceramic/high-chromium cast iron-based honeycomb structure composite material can be obtained, and the structure composite material The macroscopic photo is shown in Figure 2. It can be seen from Figure 2 that the composite material is composed of a composite area and a metal area, and the honeycomb structure does not collapse. The titanium carbonitride reinforcement in the composite area is uniformly dispersed in the matrix without agglomeration Phenomenon, no obvious defects in the complex zone.

The titanium carbonitride-reinforced high-chromium cast iron-based honeycomb composite material (volume wear rate 70.7mm ³ /h) prepared by the invention has a wear resistance that is 4.1% higher than that of traditional high-chromium cast iron (volume wear rate 290mm ³ /h) times, which is 2.2 times higher than that of the whole layer composite titanium carbonitride reinforced high chromium cast iron matrix composite material (volume wear rate 155.5mm ³ /h).

Example 2

This embodiment relates to a method for preparing a ceramic/high manganese steel-based honeycomb structure composite material, and the specific steps are as follows:

(1) Dissolve ferric nitrate nonahydrate in citric acid solution, and control the molar ratio of ferric nitrate nonahydrate and citric acid in the solution to 1:0.6, then put the mixed solution into a water bath, and heat it at a constant temperature at 60°C 12h, the sol ① was obtained.

(2) Add activated carbon with a particle size of 10nm to the hydrated titanium dioxide solution, wherein the molar ratio of hydrated titanium dioxide to nano-activated carbon is 1:1.2, and after high-speed stirring, put the mixed solution into a water bath, and heat it at a constant temperature at 70°C for 4 hours. Sol ② was obtained.

(3) Mix the sol ① obtained in step (1) with the sol ② obtained in step (2) according to the molar ratio of Fe ions and Ti ions at a ratio of 1:0.4, and then put the mixture into a vacuum drying oven and dry at 150 It was dried at ℃ for 14h to obtain a mixed gel.

(4) The mixed gel obtained in step (3) was calcined in a nitrogen atmosphere at 1400°C for 4h, and then calcined in an air atmosphere at 1000°C for 3h to obtain a mixed powder of titanium carbonitride and iron oxide.

(5) Put the mixed powder into the hydrogen reduction furnace, the temperature of the hydrogen reduction furnace is 600°C, the hydrogen flow rate is 2.0m ³ /h, and the time is 4h, to obtain the mixed powder of titanium carbonitride and iron.

(6) Mix the mixed powder with ethylene-vinyl acetate copolymer binder evenly, wherein the molar ratio of ethylene-vinyl acetate copolymer and mixed powder is 0.04:1, and form a honeycomb shape after curing at 130°C for 6 hours Prefab.

(7) Put the prefabricated body into the pouring cavity, then pour the smelted high manganese steel melt, and after cooling, the titanium carbonitride ceramic/high manganese steel matrix composite material with honeycomb structure can be obtained.

The titanium carbonitride reinforced high-manganese steel-based honeycomb structure composite material (volume wear rate 60.2mm ³ /h) prepared by the invention has improved wear resistance compared with traditional high-manganese steel (volume wear rate 240.6mm ³ /h) 4 times, which is 2.1 times higher than that of the whole layer composite titanium carbonitride reinforced high manganese steel matrix composite material (volume wear rate 126.4mm ³ /h).

Example 3

This embodiment relates to a method for preparing a ceramic/alloy steel-based honeycomb structure composite material, and the specific steps are as follows:

(1) Dissolve ferric nitrate nonahydrate in citric acid solution, and control the molar ratio of ferric nitrate nonahydrate and citric acid in the solution to 1:1.2, then put the mixed solution into a water bath, and heat it at a constant temperature at 90°C 8h, the sol ① was obtained.

(2) Add activated carbon with a particle size of 30nm to the hydrated titanium dioxide solution, wherein the molar ratio of hydrated titanium dioxide and nano-activated carbon is 1:0.8, and after high-speed stirring, put the mixed solution into a water bath, and heat it at a constant temperature at 40°C for 8 hours. Sol ② was obtained.

(3) Mix the sol ① obtained in step (1) with the sol ② obtained in step (2) according to the molar ratio of Fe ions and Ti ions at a ratio of 1:0.02, and then put the mixture in a vacuum drying oven and dry at 100 It was dried at ℃ for 20 h to obtain a mixed gel.

(4) The mixed gel obtained in step (3) was calcined in a nitrogen atmosphere at 1600°C for 2h, and then calcined in an air atmosphere at 800°C for 5h to obtain a mixed powder of titanium carbonitride and iron oxide.

(5) Put the mixed powder into the hydrogen reduction furnace, the temperature of the hydrogen reduction furnace is 800°C, the hydrogen flow rate is 1.0m ³ /h, and the time is 6h, to obtain the mixed powder of titanium carbonitride and iron.

(6) Mix the mixed powder with ethylene-vinyl acetate copolymer binder evenly, wherein the molar ratio of ethylene-vinyl acetate copolymer and mixed powder is 0.03:1, and form a honeycomb shape after curing at 90°C for 10 hours Prefab.

(7) Put the prefabricated body into the pouring cavity, then pour the smelted alloy steel melt, and after cooling, the titanium carbonitride ceramic/alloy steel-based honeycomb composite material can be obtained.

The titanium carbonitride-reinforced alloy steel-based honeycomb structure composite material (volume wear rate 86.4mm ³ /h) prepared by the invention has a wear resistance 4.2 times higher than that of traditional alloy steel (volume wear rate 362.7mm ³ /h) , which is 2 times higher than that of the whole layer composite titanium carbonitride reinforced alloy steel matrix composite material (volume wear rate 172.8mm ³ /h).

Example 4

This embodiment relates to a preparation method of a ceramic-reinforced high-chromium cast iron-based honeycomb structure composite material, and the specific steps are as follows:

(1) Dissolve ferric nitrate nonahydrate in citric acid solution, and control the molar ratio of ferric nitrate nonahydrate and citric acid in the solution to 1:0.8, then put the mixed solution in a water bath, and heat it at a constant temperature at 75°C After 9.5h, the sol ① was obtained.

(2) Add activated carbon with a particle size of 25nm to the hydrated titanium dioxide solution, wherein the molar ratio of hydrated titanium dioxide and nano-sized activated carbon is 1:1.1, and after high-speed stirring, put the mixed solution into a water bath and heat at a constant temperature of 55°C for 6.5h , to obtain sol②.

(3) Mix the sol ① obtained in step (1) with the sol ② obtained in step (2) according to the molar ratio of Fe ions and Ti ions at a ratio of 1:0.13, and then put the mixture into a vacuum drying oven and dry at 125 It was dried at ℃ for 13h to obtain a mixed gel.

(4) The mixed gel obtained in step (3) was calcined in a nitrogen atmosphere at 1450°C for 3.5h, and then calcined in an air atmosphere at 950°C for 2.5h to obtain a mixed powder of titanium carbonitride and iron oxide.

(5) Put the mixed powder into the hydrogen reduction furnace, the temperature of the hydrogen reduction furnace is 650°C, the hydrogen flow rate is 1.4m ³ /h, and the time is 5.5h to obtain the mixed powder of titanium carbonitride and iron.

(6) Mix the mixed powder and starch paste binder evenly, wherein the molar ratio of starch paste and mixed powder is 0.025:1, and form a honeycomb shape preform after curing at 1150°C for 7.5 hours.

(7) Put the prefabricated body into the pouring cavity, then pour the smelted high-chromium cast iron melt into it, and after cooling, the titanium carbonitride ceramic/high-chromium cast iron-based honeycomb composite material can be obtained.

The titanium carbonitride-reinforced high-chromium cast iron-based honeycomb structure composite material (volume wear rate 72.5mm ³ /h) prepared by the invention has improved wear resistance by 4% compared with traditional high-chromium cast iron (volume wear rate 290mm ³ /h) times, which is 2.1 times higher than that of the whole layer composite titanium carbonitride reinforced high chromium cast iron matrix composite material (volume wear rate 155.5mm ³ /h).

Claims (8)

1. The preparation method of the ceramic/iron-based honeycomb structural composite material is characterized by comprising the following steps of:

(1) Dissolving ferric nitrate nonahydrate in a citric acid solution, controlling the proportion of the ferric nitrate nonahydrate to the citric acid in the solution, and then placing the mixed solution into a water bath kettle for constant-temperature heating to obtain sol (1);

(2) Adding nano active carbon into the hydrated titanium dioxide solution, stirring at a high speed, and then placing the mixed solution into a water bath kettle for constant temperature heating to obtain sol (2);

(3) Uniformly mixing the sol (1) obtained in the step (1) and the sol (2) obtained in the step (2) according to a proportion, and performing vacuum drying treatment to obtain mixed gel;

(4) Placing the mixed gel obtained in the step (3) in nitrogen for high-temperature calcination, roasting to obtain mixed powder of titanium carbonitride and ferric oxide, and then placing the mixed powder into a reduction furnace for reduction by reducing gas to obtain mixed powder of titanium carbonitride and ferric oxide;

(5) Uniformly stirring the mixed powder obtained in the step (4) and a binder, filling the mixed powder into the honeycomb wall of a honeycomb structure die, solidifying the mixed powder to form a preform, and pouring a steel melt to obtain the titanium carbonitride ceramic reinforced iron-based honeycomb structure composite material;

the molar ratio of the ferric nitrate to the citric acid in the step (1) is 1 (0.6-1.2);

the molar ratio of the hydrated titanium dioxide to the nanometer activated carbon in the step (2) is 1 (0.8-1.2);

the molar ratio of Fe ions in the sol (1) to Ti ions in the sol (2) is 1 (0.02-0.4);

and (5) the mol ratio of the binder to the mixed powder of titanium carbonitride and iron is (0.02-0.04) 1.

2. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the heating conditions of the water bath kettle in the step (1) are as follows: heating at 60-90deg.C for 8-12 hr.

3. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the granularity of the nano activated carbon in the step (2) is 10-30nm.

4. A method of preparing a ceramic/iron-based honeycomb structured composite according to claim 1 or 3, characterized by: the heating conditions of the water bath kettle in the step (2) are as follows: heating at 40-70deg.C for 4-8 hr.

5. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the drying conditions in the step (3) are as follows: drying in vacuum drying oven at 100-150deg.C for 14-20 hr.

6. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the calcining and roasting conditions in the step (4) are as follows: calcining at 1400-1600 deg.C for 2-4 hr in nitrogen atmosphere and calcining at 800-1000 deg.C for 3-5 hr in air atmosphere.

7. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the reducing gas used in the reducing process in the step (4) is hydrogen, the temperature of the reducing furnace is 600-800 ℃, and the flow of the hydrogen is 1.0-2.0m ³ And/h, wherein the time is 4-6h.

8. The method for preparing the ceramic/iron-based honeycomb structural composite material according to claim 1, wherein the method comprises the following steps: the binder in the step (5) is any one of polyvinyl alcohol, ethylene-vinyl acetate copolymer and starch paste; the curing conditions are as follows: curing for 6-10h at 90-130 ℃ in an incubator.

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