CN106216638A - The preparation method of wearing piece - Google Patents

Abstract

The present invention provides the preparation method of a kind of wearing piece, and described wearing piece is made up of matrix and attachment wearing layer on the matrix, comprises the steps: step 1, prepares the prefabricated section corresponding with described wearing layer shape；Step 2, prepares matrix apperance with white mould；Step 3, lost foam casting.The wearing layer cost of material of wearing piece prepared by the present invention is low, and the wearing layer hardness prepared is high, abrasion resistance is high, and service life is long, is suitable under very severe working condition using.

Description

Preparation method of wear-resistant parts

technical field

The invention relates to a wear-resistant part, in particular to a preparation method of a wear-resistant part in which a wear-resistant material is combined with a base material of the wear-resistant part.

Background technique

Wear-resistant parts such as guide and guard plates are one of the important wearing parts with large consumption in the rolling steel production line, and their service life directly affects the production efficiency of the rolling mill. The working environment of the guide plate is very harsh. For example, it needs to withstand the large impact of high-temperature steel, thermal load, strong wear, extrusion and cooling of water spray during the working process. The failure mode of the guard plate is mainly high temperature oxidation wear and fatigue spalling, so the guard plate is required to have high strength, hardness and wear resistance, as well as high impact toughness, thermal fatigue resistance, thermal stability and resistance Oxidation. At present, the main preparation methods of guide boards are:

1. Add some reinforcements to the alloy layer to improve its performance, but the working environment of the guide plate is high temperature, the hardness of the alloy will decrease, and the reinforcement particles are easy to fall off from the matrix, thus affecting the wear resistance of the guide plate.

2. Chinese invention patent CN101053898 discloses a vacuum full-form infiltration method for preparing particle-reinforced metal-based surface composite materials. The reinforcement particles are prepared into prefabricated blocks that adapt to the shape of the wear-resistant surface and fixed on the foam that needs to be alloyed. On the surface of the model, the model is buried in dry sand and poured to obtain a dense composite layer, a relatively uniform distribution of reinforcements and good impact and wear resistance. However, the PVA binder is easy to volatilize at high temperature, resulting in unstable overall structure of the wear-resistant layer, slightly poor hardness, short service life, and high production cost of the wear-resistant layer.

3. Chinese invention patent CN1706635 discloses a bimetal composite guide plate and its preparation method. The guide plate is composed of a substrate and a wear-resistant layer. The substrate is medium-carbon steel or low-alloy steel with good toughness, and the wear-resistant layer is high vanadium. High-speed steel, the production method is to form the matrix and wear-resistant layer by casting, so that the matrix and wear-resistant layer form a good metallurgical bond, and obtain a high-hardness and high-wear-resistant working layer. The process requires two sets of independent equipment, the process is complicated, and the combined quality is not easy to control.

4. Chinese invention patent CN1142435 discloses a welded ceramic composite guide plate. A composite guide plate with carbon fiber ceramic material as the working surface of the guide plate has been developed. The upper layer is the working layer and the lower layer is the welding layer, which has thermal conductivity. Good resistance, high wear resistance, high thermal shock resistance and toughness, but the ceramic material is brazed with the guide plate substrate, and the ceramic layer is easy to peel off, resulting in poor reliability of the guide plate and affecting production efficiency.

Contents of the invention

The object of the present invention is to provide a method for manufacturing a wear-resistant part, which can at least solve the above-mentioned problems in the prior art.

In order to achieve the above object, the present invention provides the following technical solutions:

A method for preparing a wear-resistant part, the wear-resistant part is composed of a substrate and a wear-resistant layer attached to the substrate, comprising the following steps:

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer

Step 1.1, preparing ceramic particles and high-alloy cast iron, wherein the high-alloy cast iron is one or more of ferrosilicon, ferrovanadium, and white iron,

Step 1.2, uniformly mixing the high-alloy cast iron and the ceramic particles,

Step 1.3, add resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly,

Step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for the resin to solidify, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer;

Step 2, prepare the matrix pattern with a white mold

Cutting the commercially available white mold into the shape and size of the required matrix to obtain the pattern of the matrix;

Step 3, lost foam casting

Step 3.1, placing the prefabricated block at the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer to the matrix pattern with an adhesive,

Step 3.2, spraying refractory paint on the substrate pattern of the product obtained in step 3.1 and the free surface of the prefabricated block and drying,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum,

Step 3.4, after the dry sand is fastened and shaped, pour molten metal at 1500-1600°C into the mold, the matrix pattern is heated and vaporized and extracted, and the molten metal completely replaces the position of the matrix pattern, so The wear-resistant part is obtained after the molten metal is cooled and solidified.

Further, in the above preparation method, in the step 1, the mass of the high-alloy cast iron accounts for 35-70% of the total mass of the prefabricated block, and the mass of the ceramic particles accounts for 35-70% of the total mass of the prefabricated block. 25-60%, the mass of the resin accounts for 2-5% of the total mass of the prefabricated block.

Further, in the above preparation method, in the step 1, the high-alloy cast iron is ball-milled to 70-150 μm.

Further, in the above preparation method, in the step 1, the resin is an alcohol-soluble resin.

Further, in the above preparation method, in the step 1, the particle size of the ceramic particles is 20-100 μm.

Further, in the above preparation method, in the step 3.2, the coating thickness of the refractory paint sprayed on the free surface of the substrate pattern is 0.5-2mm.

Further, in the above preparation method, in the step 3.2, the refractory coating is a water-based coating.

Further, in the above preparation method, in the step 3.2, the drying temperature is 40-50°C.

Further, in the above preparation method, in the step 1, tungsten carbide powder is also included, and the tungsten carbide powder is uniformly mixed with the product obtained in step 1.2, and then resin is added to continue mixing and stirring evenly.

Further, in the above preparation method, in the step 1, the particle size of the tungsten carbide powder is 10-40 μm.

It can be seen from the analysis that the invention discloses a preparation method of a wear-resistant part. The technical solution of the present invention is because the carbon and carbide produced by the combustion of the base pattern produced by the white mold and the reducing atmosphere are sucked away during the pouring process to form a vacuum environment, which improves the filling capacity of the molten metal and avoids the need for filling the mold with the molten metal. Oxidized, the gas will not enter the molten metal, avoiding the occurrence of defects, and at the same time, it is also conducive to the penetration of the molten metal between the alloy particles of the wear-resistant layer. After metallurgical bonding, a dense composite layer is formed to prevent the alloy layer from falling off, thus obtaining high wear resistance. Grinding, high hardness wear parts. In addition, the raw material cost of the wear-resistant layer of the wear-resistant part of the present invention is low, and the prepared wear-resistant layer has high hardness, high wear resistance, long service life, and is suitable for use under very severe working conditions.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. in:

Figure 1 is a schematic diagram of the working part of the wear-resistant part;

Fig. 2 is a schematic sectional view along A-A in Fig. 1;

Fig. 3 is a microstructure diagram of the bonding surface between the wear-resistant layer and the substrate.

Explanation of reference numerals: 1 wear-resistant layer; 2 matrix.

detailed description

The present invention will be described in detail below with reference to the accompanying drawings and examples. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

As shown in Figures 1 to 3, according to an embodiment of the present invention, a method for preparing a wear-resistant part is provided. The wear-resistant part is composed of a substrate 2 and a wear-resistant layer 1 attached to the substrate 2, including the following steps:

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, preparing ceramic particles and high-alloy cast iron, wherein the high-alloy cast iron is one or more of ferrosilicon, ferrovanadium, and white iron,

Step 1.2, mix high-alloy cast iron and ceramic particles evenly,

Step 1.3, add resin on the basis of the product obtained in step 1.2 and continue to mix and stir evenly, so that the resin is evenly distributed in the high-alloy cast iron powder and ceramic particles,

Step 1.4, pour the product obtained in step 1.3 into a mold, wait for 30 minutes after pressing, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the resin is cured;

Step 2, prepare the matrix pattern with a white mold

The commercially available white mold is cut into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and the position of the prefabricated block of the wear-resistant layer 1 is reserved at the position where it needs to be combined with the wear-resistant layer 1 . Further, using a resistance wire cutting device to cut the white mold can accurately cut the white mold according to the shape and size of the base 2 to obtain the base pattern. When pouring, the molten metal replaces the shape of the matrix and becomes the matrix 2.

Step 3, lost foam casting

Step 3.1, place the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connect the prefabricated block of the wear-resistant layer 1 with the matrix pattern with an adhesive, which can be a hydrophilic inorganic adhesive ( High temperature binder): Any one such as clay, bentonite, water glass, silica sol, phosphate, sulfate, polyaluminum chloride, etc. can be used.

Step 3.2, spraying refractory paint on the free surface of the base pattern and the prefabricated block obtained in step 3.1 and drying, the refractory paint is coated on the surface of the base pattern, so that the pyrolysis product of the matrix pattern can be discharged through the coating of the refractory paint , but the coating will not infiltrate molten metal. Spraying refractory coatings also has the following functions: it can reduce the surface roughness value of castings; it helps to prevent or reduce defects such as sand sticking and sand holes in castings; Sand efficiency; it can make the gas and liquid products of the pyrolysis of the matrix pattern in the air gap at the front of the molten metal flow pass smoothly, and be discharged into the mold, but it must also prevent the infiltration of the molten metal; it can improve the strength and rigidity of the matrix pattern, Prevent the pattern from being deformed and damaged during transportation and sand filling vibration. The refractory coating of the present invention can be a conventional commercially available refractory coating, such as the special coating for lost foam casting produced by Jining Tianshi Paint Co., Ltd., because the casting temperature is high, so the strength requirement of the coating is also high, the higher the pouring temperature, the foam pattern And the gas generation of the coating itself is larger, and the gas permeability of the required coating is also better, so the coating pays more attention to the refractoriness and thermochemical stability. The composition of the refractory coating includes refractory aggregate (corundum powder, zircon powder, magnesium oxide powder), carrier (general water), binder (clay, silica sol, syrup, white latex, water glass, etc.), suspending agent (bentonite, clay, organic polymer compound), active agent, degreasing agent, defoamer Wait. Preferably, the refractory coating of the present invention is composed of the following components by weight percentage: 80% of zircon powder, 10% of corundum powder, 4% of bentonite, 5% of syrup, and 1% of white latex; It can be used after uniformity, and the mass ratio of water and refractory coating is preferably 1:1.

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum, and the subsequent pouring process is under this vacuum degree After completion, the degree of vacuum is controlled at a negative pressure of 0.015-0.05MPa, more preferably, the degree of vacuum is 0.03-0.04MPa, and the defect of the casting will not be caused under this degree of vacuum.

Step 3.4, after the dry sand is fastened and formed, pour molten metal at 1500-1600°C (such as 1520°C, 1550°C, 1560°C, 1570°C, 1590°C) into the mold, the matrix pattern is vaporized by heat and drawn out, and the metal The metal liquid completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the metal liquid is cooled and solidified, and the box is turned over to take out the wear-resistant parts.

The technical solution of the present invention is because the carbon and carbide produced by the combustion of the matrix pattern and the reducing atmosphere are taken away during the pouring process to form a vacuum environment, which improves the filling capacity of the molten metal and avoids the molten metal from being oxidized when filling the mold. It will not enter the interior of the molten metal, avoiding the occurrence of defects, and at the same time, it is also conducive to the penetration of the molten metal between the alloy particles of the prefabricated block of the wear-resistant layer 1, forming a dense composite at the junction of the matrix 2 and the prefabricated block of the wear-resistant layer 1 layer to prevent the wear-resistant layer 1 from falling off the substrate 2, thereby obtaining a wear-resistant part with high wear resistance and high hardness.

Further, in step 1, the mass of high-alloy cast iron accounts for 35-70% of the total mass of the prefabricated block of wear-resistant layer 1, the mass of ceramic particles accounts for 25-60% of the total mass of the prefabricated block of wear-resistant layer 1, and the resin The mass accounts for 2-5% of the total mass of the prefabricated block of wear-resistant layer 1. The wear-resistant layer 1 obtained by the above ratio has higher wear resistance, is applicable to harsher working conditions, and has cheaper raw material prices. The ceramic particles are preferably one of aluminum oxide and silicon carbide, or both aluminum oxide and silicon carbide, and the weights of aluminum oxide and silicon carbide are equal, and the particle size of the ceramic particles is preferably 20-100 μm (such as 25 μm, 30 μm , 40μm, 50μm, 65μm, 80μm, 85μm, 90μm). The ceramic particles with this particle size can be better mixed with other raw materials of the wear-resistant layer, and are not easy to fall off from the wear-resistant layer 1. The wear-resistant layer 1 has a higher degree of wear resistance, which enhances the service life of the wear-resistant layer.

Further, in step 1, the high-alloy cast iron is ball-milled to 70-150 μm, that is, one or more of ferrosilicon, ferrosilicon, and white iron is ball-milled to 70-150 μm (such as 80 μm, 90 μm, 100 μm, 110 μm , 130μm, 140μm), can mix more evenly with ceramic particles.

Further, in step 1, the resin is an alcohol-soluble resin, such as a commercially available phenolic resin. Alcohol-soluble resin has good solubility, environmental protection, good adhesion, excellent oxidation resistance, high bonding strength, easy curing, and convenient construction.

Further, in step 3.2, the coating thickness of the refractory coating sprayed on the free surface of the matrix pattern is 0.5-2mm (such as 0.8mm, 1mm, 1.2mm, 1.5mm, 1.7mm), and the refractory coating is a commercially available water-based For the paint, in step 3.2, the drying temperature is 40-50°C (such as 42°C, 44°C, 45°C, 46°C, 48°C), and the drying time is 2-4 hours. If the coating thickness is greater than 2mm, the drying temperature will increase accordingly, and the stress generated by drying shrinkage will be greater, the crack tendency will be greater, and the air permeability will be poorer.

Further, when the required hardness of the wear-resistant layer 1 is higher than 60HRA, in step 1, tungsten carbide powder is also included, and the tungsten carbide powder is evenly mixed with the product obtained in step 1.2, and then resin is added to continue mixing and stirring evenly, adding carbonized Tungsten powder can significantly increase the hardness of the wear-resistant layer 1 . Preferably, the amount of tungsten carbide powder accounts for 25%-30% of the total weight of the prefabricated block, and the particle size of the tungsten carbide powder is preferably 10-40 μm (such as 15 μm, 20 μm, 25 μm, 30 μm, 35 μm), which can be combined with high alloy cast iron And the mixing of ceramic particles is more uniform, and the density and hardness of the prepared wear-resistant layer 1 are higher.

In the invention, the prefabricated block and the matrix are bonded together with a binder, which is not easy to fall off during the process of spraying paint and drying, and can obtain a stable cast-infiltrated wear-resistant layer. However, the PVA binder used in the technical solution of the prior art CN101053898 is easy to volatilize at high temperature, which causes the overall structure of the wear-resistant layer to be unstable, the hardness is slightly poor, the service life is relatively short, and the production cost of the wear-resistant layer is high.

Example 1

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, prepare the high-alloy cast iron (grain size is 70-90 μm) that accounts for 35% of the total mass of the prefabricated block, wherein: ferrovanadium: ferrosilicon: white iron (mass ratio) = 0.5: 2: 1, add ferrovanadium in the steel After that, the hardness, strength, wear resistance and ductility of the steel can be significantly improved, and the cutting performance of the steel can be improved. The composition and mass percentage of vanadium iron (FeV60) are: V60%, Si2%, Al2.5%, C0 .06%, P0.05%, S0.05%, CU0.1%, others are iron, ferrosilicon is a deoxidizer, used for precipitation deoxidation and diffusion deoxidation, can significantly improve the strength, hardness and elasticity of steel, and improve the The magnetic permeability can reduce the hysteresis loss of transformer steel, the composition and mass percentage of ferrosilicon (FeSi25): Si25%, Al20%, P20%, C1.5%, Ti1%, others are iron, white Iron is hard, wear-resistant, and has good castability. Its composition and mass percentage are C2.11%-4.3%, P1.2%, S0.06%, Si2-3%, Mn0.5%, and the rest is iron. Alumina ceramic particles (20-30 μm in size) accounting for 60% of the total mass of the prefabricated block,

Step 1.2, mix high-alloy cast iron and ceramic particles evenly,

Step 1.3, add phenolic resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly, the quality of the resin accounts for 5% of the total mass of the prefabricated block,

In step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for 30 minutes, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the phenolic resin is cured.

Step 2, use the white mold to prepare the shape of the base 2

Use resistance wire to cut the commercially available white mold into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and reserve the placement position of the prefabricated block of the wear-resistant layer 1 at the position where it needs to be combined with the wear-resistant layer 1 .

Step 3, lost foam casting

Step 3.1, placing the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer with the matrix pattern with an adhesive,

In step 3.2, spray the refractory coating on the base pattern of the product obtained in step 3.1 and the free surface of the prefabricated block and dry it. The coating thickness of the refractory coating sprayed on the surface of the white mold is 0.5 mm, and the drying temperature is 40 ° C. The drying time is 3h,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum, the vacuum degree is 0.03MPa,

Step 3.4, after the dry sand is fastened and formed, pour 1500°C molten metal into the mold, the matrix pattern is heated and vaporized and extracted, the molten metal completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the molten metal is cooled and solidified , Turn over the box and take out the wear parts.

The wear resistance of the wear-resistant layer 1 of the wear-resistant part prepared in this embodiment: compared with 45 steel, under the same conditions, the friction and wear weight loss rate of the wear-resistant layer 1 is 1/ of the friction and wear weight loss rate of 45 steel 6.5.

Example 2

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, prepare the high-alloy cast iron (grain size is 80-100 μm) that accounts for 38% of the total mass of the prefabricated block, wherein: ferrovanadium: ferrosilicon: white iron (mass ratio)=1: 2: 1, accounting for the total mass of the prefabricated block 60% alumina ceramic particles (30-50μm particle size),

Step 1.2, mix high-alloy cast iron and ceramic particles evenly,

Step 1.3, add phenolic resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly, the quality of the resin accounts for 2% of the total mass of the prefabricated block,

In step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for 30 minutes, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the phenolic resin is cured.

Step 2, use the white mold to prepare the shape of the base 2

Use resistance wire to cut the commercially available white mold into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and reserve the placement position of the prefabricated block of the wear-resistant layer 1 at the position where it needs to be combined with the wear-resistant layer 1 .

Step 3, lost foam casting

Step 3.1, placing the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer with the matrix pattern with an adhesive,

Step 3.2: Spray and dry the refractory coating on the base pattern of the product obtained in step 3.1 and the free surface of the prefabricated block. The coating thickness of the refractory coating sprayed on the surface of the white mold is 1mm, and the drying temperature is 42°C. The time is 4h,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum, the vacuum degree is 0.035MPa,

Step 3.4, after the dry sand is fastened and formed, pour molten metal at 1520°C into the mold, the matrix pattern is heated and vaporized and extracted, and the molten metal completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the molten metal is cooled and solidified , Turn over the box and take out the wear parts.

The wear resistance of the wear-resistant layer 1 of the wear-resistant part prepared in this embodiment: compared with 45 steel, under the same conditions, the friction and wear weight loss rate of the wear-resistant layer 1 is 1/ of the friction and wear weight loss rate of 45 steel 7.

Example 3

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, prepare the high-alloy cast iron (grain size is 100-120 μm) that accounts for 70% of the total mass of the prefabricated block, wherein: ferrovanadium: ferrosilicon: white iron (mass ratio)=0.5: 2: 0.5, accounting for the total mass of the prefabricated block 25% alumina ceramic particles (60-80μm particle size),

Step 1.2, mix high-alloy cast iron and ceramic particles evenly,

Step 1.3, add phenolic resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly, the quality of the resin accounts for 5% of the total mass of the prefabricated block,

In step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for 30 minutes, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the phenolic resin is cured.

Step 2, use the white mold to prepare the shape of the base 2

Use resistance wire to cut the commercially available white mold into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and reserve the placement position of the prefabricated block of the wear-resistant layer 1 at the position where it needs to be combined with the wear-resistant layer 1 .

Step 3, lost foam casting

Step 3.1, placing the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer with the matrix pattern with an adhesive,

In step 3.2, spray the refractory coating on the base pattern of the product obtained in step 3.1 and the free surface of the prefabricated block and dry it. The coating thickness of the refractory coating sprayed on the surface of the white mold is 1.5 mm, and the drying temperature is 45 ° C. The drying time is 2h,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect it to the vacuum system to suck the vacuum, the vacuum degree is 0.038MPa,

Step 3.4, after the dry sand is fastened and formed, pour molten metal at 1550°C into the mold, the matrix pattern is heated and vaporized and extracted, and the molten metal completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the molten metal is cooled and solidified , Turn over the box and take out the wear parts.

The wear resistance of the wear-resistant layer 1 of the wear-resistant part prepared in this embodiment: compared with 45 steel, under the same conditions, the friction and wear weight loss rate of the wear-resistant layer 1 is 1/ of the friction and wear weight loss rate of 45 steel 6.

Example 4

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, prepare the high-alloy cast iron (grain size is 130-150 μm) that accounts for 55% of the total mass of the prefabricated block, wherein: ferrovanadium: ferrosilicon: white iron (mass ratio)=1:1:2, accounting for the total mass of the prefabricated block 30% ceramic particles (particle size 80-100μm), accounting for 10% of the total mass of tungsten carbide powder, the particle size of tungsten carbide powder is 10μm,

Step 1.2, mix high-alloy cast iron, ceramic particles and tungsten carbide powder evenly,

Step 1.3, add phenolic resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly, the quality of the resin accounts for 5% of the total mass of the prefabricated block,

In step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for 30 minutes, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the phenolic resin is cured.

Step 2, use the white mold to prepare the shape of the base 2

Use resistance wire to cut the commercially available white mold into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and reserve the placement position of the prefabricated block of the wear-resistant layer 1 at the position where it needs to be combined with the wear-resistant layer 1 .

Step 3, lost foam casting

Step 3.1, placing the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer with the matrix pattern with an adhesive,

Step 3.2: Spray and dry the refractory coating on the base pattern of the product obtained in step 3.1 and the free surface of the prefabricated block. The coating thickness of the refractory coating sprayed on the surface of the white mold is 2 mm, and the drying temperature is 48 ° C. The time is 3h,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum, the vacuum degree is 0.04MPa,

Step 3.4, after the dry sand is fastened and shaped, pour molten metal at 1580°C into the mold, the matrix pattern is heated and vaporized and drawn out, the molten metal completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the molten metal is cooled and solidified , Turn over the box and take out the wear parts.

The wear resistance of the wear-resistant layer 1 of the wear-resistant part prepared in this embodiment: compared with 45 steel, under the same conditions, the friction and wear weight loss rate of the wear-resistant layer 1 is 1/ of the friction and wear weight loss rate of 45 steel 7. The hardness of the wear-resistant layer 1 is as high as 70HRA.

Example 5

Step 1, preparing a prefabricated block corresponding to the shape of the wear-resistant layer 1

Step 1.1, prepare the high-alloy cast iron (grain size is 130-150 μm) that accounts for 55% of the total mass of the prefabricated block, wherein: ferrovanadium: ferrosilicon: white iron (mass ratio)=1: 2: 2, accounting for the total mass of the prefabricated block 30% ceramic particles (grain size 20-50 μm), tungsten carbide powder accounting for 10% of the total mass of the prefabricated block, the particle size of tungsten carbide powder is 40 μm,

Step 1.2, mix high-alloy cast iron, ceramic particles and tungsten carbide powder evenly,

Step 1.3, add phenolic resin on the basis of the preparation in step 1.2 and continue to mix and stir evenly, the quality of the resin accounts for 5% of the total mass of the prefabricated block,

In step 1.4, pour the product obtained in step 1.3 into a mold, press and wait for 30 minutes, and prepare a prefabricated block corresponding to the shape of the wear-resistant layer 1 after the phenolic resin is cured.

Step 2, use the white mold to prepare the shape of the base 2

Use resistance wire to cut the commercially available white mold into the shape and size of the required matrix 2 to obtain the pattern of the matrix, and reserve the placement position of the prefabricated block of the wear-resistant layer 1 at the position where it needs to be combined with the wear-resistant layer 1 .

Step 3, lost foam casting

Step 3.1, placing the prefabricated block of the wear-resistant layer 1 on the corresponding position of the matrix pattern, and connecting the prefabricated block of the wear-resistant layer with the matrix pattern with an adhesive,

Step 3.2: Spray and dry the refractory coating on the base pattern of the product obtained in step 3.1 and the free surface of the prefabricated block. The coating thickness of the refractory coating sprayed on the surface of the white mold is 2mm, and the drying temperature is 50°C. The time is 2.5h,

Step 3.3, put the product obtained in step 3.2 into the sand box, fill it with dry sand, put the sprue cup on it, cover it with a plastic film, connect the vacuum system to suck the vacuum, the vacuum degree is 0.03MPa,

Step 3.4, after the dry sand is fastened and formed, pour 1600°C molten metal into the mold, the matrix pattern is heated and vaporized and extracted, the molten metal completely replaces the position of the matrix pattern, and the wear-resistant parts are obtained after the molten metal is cooled and solidified , turn over the box, and take out the wear parts.

The wear resistance of the wear-resistant layer 1 of the wear-resistant part prepared in this embodiment: compared with 45 steel, under the same conditions, the friction and wear weight loss rate of the wear-resistant layer 1 is 1/ of the friction and wear weight loss rate of 45 steel 6. The hardness of wear-resistant layer 1 is as high as 78HRA.

Example 6

Only step 1.1 is different from embodiment 1, and other processes are the same as embodiment 1. The step 1.1 of the present embodiment is: prepare the high-alloy cast iron that accounts for 35% of the prefabricated block gross mass, wherein: ferrovanadium: ferrosilicon: white iron ( Mass ratio) = 0.5:2:1, the alumina ceramic particles (100-120 μm in size) accounting for 60% of the total mass of the prefabricated block, and the particle size of the high-alloy cast iron after ball milling are 155-170 μm.

This embodiment 6 prepares the wear resistance of the wear-resistant layer 1 of the wear-resistant part: compared with 45 steel, under the same conditions, the friction and wear weight loss of the wear-resistant layer 1 is 1 of the friction and wear weight loss of 45 steel /5.5.

Example 7

Only step 1.1 is different from embodiment 1, and other processes are the same as embodiment 1, and the step 1.1 of the present embodiment is: prepare the high-alloy cast iron that accounts for 75% of the prefabricated block gross mass, wherein: ferrovanadium: ferrosilicon: white iron ( Mass ratio) = 0.5:2:1, alumina ceramic particles (10-30 μm in particle size) accounting for 20% of the total mass of the prefabricated block, 106-150 μm in particle size after ball milling of high-alloy cast iron, and resin accounting for 5% of the total mass.

This embodiment 6 prepares the wear resistance of the wear-resistant layer 1 of the wear-resistant part: compared with 45 steel, under the same conditions, the friction and wear weight loss of the wear-resistant layer 1 is 1 of the friction and wear weight loss of 45 steel /5.

comparative example

Only step 1 is different from embodiment 1, and other processes are the same as embodiment 1. The step 1 of this comparative example is: the particle size is 250-380 μ m tungsten carbide particles 60 g, particle size is 180-250 μ m high carbon ferrochrome particles 40 g, and poly Vinyl alcohol aqueous solution PVA (concentration is 6wt%) is mixed evenly, and the addition is 6wt% of prefabricated body total weight, and the composition of high-carbon ferrochrome is FeCr55C1000, and the granule after mixing is pressed and heated and dried 1h under the condition of 50 degree, thereby Get prefab blocks.

This comparative example prepares the wear resistance of the wear-resistant layer 1 of the wear-resistant part: compared with 45 steel, under the same conditions, the friction and wear weight loss of the wear-resistant layer 1 is 1/ of the friction and wear weight loss of 45 steel 3.5.

From the above description, it can be seen that the above-mentioned embodiments of the present invention have achieved the following technical effects:

Because the carbon and carbide produced by the burning of the white mold and the reducing atmosphere are sucked away during the pouring process, a vacuum environment is formed, which improves the filling capacity of the molten metal, avoids the oxidation of the metal during filling, and the gas will not enter the interior of the molten metal , to avoid the generation of defects, and also facilitate the penetration of molten metal between alloy particles to form a dense composite layer to prevent the alloy layer from falling off, thereby obtaining wear-resistant parts with high wear resistance and high hardness.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a preparation method for wearing piece, described wearing piece is made up of matrix and attachment wearing layer on the matrix, its It is characterised by, comprises the steps:

Step 1, prepares the prefabricated section corresponding with described wearing layer shape

Step 1.1, prepares ceramic particle and high alloy iron, and wherein said high alloy iron is among ferrosilicon, vanadium iron, white iron One or more,

Step 1.2, mixs homogeneously described high alloy iron with described ceramic particle,

Step 1.3, adds resin on the basis of the prepared thing of step 1.2 and continues mixing and stirring,

Step 1.4, pours in mould by the prepared thing of step 1.3, suppresses and after resin solidifies, prepares and described wearing layer shape The prefabricated section that shape is corresponding；

Step 2, prepares matrix apperance with white mould

Commercially available white cross cutting is slit into the shapes and sizes of required matrix, obtains described matrix apperance；

Step 3, lost foam casting

Step 3.1, is placed in the relevant position of described matrix apperance by described prefabricated section, and with pre-by described wearing layer of binding agent Clamp dog is connected with described matrix apperance,

Step 3.2, prepares the matrix apperance of thing and the Free Surface spray refractory coating of prefabricated section in step 3.1 and dries,

Step 3.3, puts in sandbox by the prepared thing of step 3.2, inserts dry sand, put cup, with covered rearing with plastic film, connect Vacuum system inhales vacuum,

Step 3.4, after the fastening molding of described dry sand, pours in casting mold by the molten metal of 1500-1600 DEG C, described matrix apperance Vaporization of being heated is drawn out of, and described molten metal all replaces the position of described matrix apperance, obtains after described molten metal cooled and solidified Described wearing piece.

Preparation method the most according to claim 1, it is characterised in that

In described step 1, the quality of described high alloy iron accounts for the 35-70% of described prefabricated section gross mass,

The quality of described ceramic particle accounts for the 25-60% of described prefabricated section gross mass,

The quality of described resin accounts for the 2-5% of described prefabricated section gross mass.

Preparation method the most according to claim 1, it is characterised in that

In described step 1, described high alloy iron is milled to 70-150 μm.

Preparation method the most according to claim 1, it is characterised in that

In described step 1, described resin is alcohol-soluble resin.

Preparation method the most according to claim 1, it is characterised in that

In described step 1, the granularity of described ceramic particle is 20-100 μm.

Preparation method the most according to claim 1, it is characterised in that

In described step 3.2, the coating layer thickness of the fireproof coating being sprayed on described matrix apperance Free Surface is 0.5-2mm.

Preparation method the most according to claim 1, it is characterised in that

In described step 3.2, described fireproof coating is water based paint.

Preparation method the most according to claim 1, it is characterised in that

In described step 3.2, the temperature of described drying is 40-50 DEG C.

Preparation method the most according to claim 1, it is characterised in that

In described step 1, also include that tungsten carbide powder, described tungsten carbide powder add after mixing homogeneously with the prepared thing of step 1.2 again Enter resin and continue mixing and stirring.

Preparation method the most according to claim 9, it is characterised in that

In described step 1, the granularity of described tungsten carbide powder is 10-40 μm.