CN104372337A - A kind of Ni-TiO2 nano-coating and preparation method thereof - Google Patents

Abstract

The present invention relates to a kind of Ni- _TiO2 nano-coating and preparation method thereof, its component and the mass percent of each component are Ni60A accounts for 71.14%-82.14%, _TiO2 accounts for 15%-26%, _CaF2 accounts for 2% , trace element accounts for 0.86%, and described trace element comprises Go, Mo, W, Ni, and its preparation method is: first adopt dry pulverization method to make the nanosphere of Ni60A and TiO ₂ , adopt active agent protection method to mix Go, Mo again , W, Ni materials to prepare nano-powders, then add 2% additive CaF ₂ , and then use laser cladding spraying process to prepare Ni-TiO ₂ coating on 4Cr13 mold steel substrate. Adding molybdenum to the material of the invention can improve the corrosion resistance of the steel, increase the strength and wear resistance of the material; the nickel-based superalloy containing _TiO2 has the characteristics of high melting point, low density and small coefficient of thermal expansion.

Description

A kind of Ni-TiO2 nano-coating and preparation method thereof

technical field

The invention relates to the technical field of thermal spraying, in particular to a Ni- _TiO2 nano coating and a preparation method thereof.

Background technique

Remanufacturing engineering with Chinese characteristics is developed on the basis of maintenance engineering and surface engineering, mainly based on composite surface engineering technology, nanometer surface engineering technology and automated surface engineering technology. These advanced surface engineering technologies are not used in foreign remanufacturing. of. The application of advanced surface engineering technology in remanufacturing can increase the utilization rate of old workpieces to 90%, so that the dimensional accuracy and quality standards of the parts are not lower than the level of the new prototype, and the wear resistance, corrosion resistance, fatigue resistance and other performance On the one hand, it can reach the level of new prototype products, and ultimately ensure that the performance and quality of remanufactured equipment parts can reach or even exceed that of new prototype products. The important feature of remanufacturing is that the quality and performance of remanufactured products are not lower than new products, the cost is only 50% of new products, energy saving is 60%, material saving is 70%, and the adverse impact on the environment is significantly reduced. An important path to a friendly society.

In the field of material surface treatment technology, laser cladding technology is a kind of high energy density surface treatment technology, which has many advantages that other surface treatment methods cannot match. Laser cladding technology refers to placing selected coating materials on the surface of the coated substrate with different filler methods, melting it and a thin layer of the substrate surface at the same time through laser irradiation, and forming a very low dilution and coating material after rapid solidification. A surface coating that forms a metallurgical combination with the base material, thereby significantly improving the wear resistance, corrosion resistance, heat resistance, oxidation resistance, and electrical properties of the base material surface. Laser cladding technology has high economic benefits. It can prepare high-performance alloy surfaces on cheap metal substrates without affecting the properties of the substrate, reduce costs, and save precious rare metal materials more than plasma spraying or flame spraying.

In view of the common problems of poor wear resistance and low corrosion resistance of existing coatings, people need a method that can be applied in the field of laser cladding technology to improve the microstructure and structure of the material surface coating and increase the hardness of the coating. of new materials.

Contents of the invention

In view of the above technical problems, the present invention provides a Ni- _TiO2 nano coating and a preparation method thereof.

The technical problem to be solved by the present invention adopts the following technical solutions to realize:

A kind of Ni-TiO Nano _- coating, its component and the mass percentage of each component are that Ni60A accounts for 71.14%-82.14%, TiO ₂ accounts for 15%-26%, CaF ₂ accounts for 2%, trace element accounts for 0.86%, The trace elements include Go, Mo, W, Ni.

A method for preparing a Ni- _TiO2 nano coating, comprising the following steps: first adopting a dry pulverization method to prepare Ni60A and _TiO2 nanospheres, and then using an active agent protection method to mix Go, Mo, W, and Ni materials to prepare nano Powder, then add 2% additive CaF ₂ , and then use laser cladding spraying process to prepare Ni-TiO ₂ coating on 4Cr13 mold steel substrate, the additive CaF ₂ can improve the toughness of the material by 100%, nickel-based White fusible alloy powder has excellent comprehensive properties such as corrosion resistance, oxidation resistance and wear resistance.

The beneficial effects of the present invention are: the present invention is superior to traditional coating materials, has high hardness and good wear resistance, is suitable for laser cladding technology, and has great progress compared with traditional alloy materials; adding molybdenum to materials can improve The corrosion resistance of steel improves the strength and wear resistance of materials; the nickel-based superalloy containing _TiO2 has the characteristics of high melting point, low density and small thermal expansion coefficient, which solves the problem of poor wear resistance and wear resistance of existing coatings. The problem of low corrosion resistance improves the microstructure and structure of the surface coating of the material, increases the hardness of the coating by 50%, and increases the elastic modulus by 8.5%-14.4%, thereby improving the wear resistance of the material surface as a whole. It is used in the manufacture of various high-temperature components in aviation and aerospace, and is an important material for modern machinery manufacturing and repair and reuse of worn parts.

Detailed ways

In order to make the technical means and creative features realized by the present invention easy to understand, the present invention will be further elaborated below.

Embodiment one:

A kind of Ni-TiO _Nano coating, its component and the mass percent of each component are that Ni60A accounts for 71.14%, _TiO accounts for 26%, CaF accounts for 2%, _and trace element accounts for 0.86%, and described trace element comprises Go , Mo, W, Ni.

A method for preparing a Ni- _TiO2 nano coating, comprising the following steps: first adopting a dry pulverization method to prepare Ni60A and _TiO2 nanospheres, and then using an active agent protection method to mix Go, Mo, W, and Ni materials to prepare nano powder, then add 2% additive CaF ₂ , and then prepare Ni-TiO ₂ coating on 4Cr13 mold steel substrate by laser cladding spraying process.

The experimental results of the performance comparison between the Ni-TiO nano _- coated workpiece and the 20Cr round steel substrate are shown in Table 1.

The experimental results of the friction and wear performance of the Ni-TiO _nano- coated workpiece are compared with the experimental results of the friction and wear performance of the 20Cr round steel substrate in Table 2.

Embodiment two:

A kind of Ni-TiO _Nano coating, its component and the mass percent of each component are that Ni60A accounts for 78.14%, _TiO accounts for 19%, CaF accounts for 2%, _and trace element accounts for 0.86%, and described trace element comprises Go , Mo, W, Ni.

A kind of Ni-TiO The preparation method of nano _- coating, with embodiment one.

The experimental results of the performance comparison between the Ni-TiO nano _- coated workpiece and the 20Cr round steel substrate are shown in Table 1.

The experimental results of the friction and wear performance of the Ni-TiO _nano- coated workpiece are compared with the experimental results of the friction and wear performance of the 20Cr round steel substrate in Table 2.

Embodiment three:

A kind of Ni-TiO _Nano coating, its component and the mass percent of each component are that Ni60A accounts for 82.14%, _TiO accounts for 15%, CaF accounts for 2%, _and trace element accounts for 0.86%, and described trace element comprises Go , Mo, W, Ni.

A kind of Ni-TiO The preparation method of nano _- coating, with embodiment one.

The experimental results of the performance comparison between the Ni-TiO nano _- coated workpiece and the 20Cr round steel substrate are shown in Table 1.

The experimental results of the friction and wear performance of the Ni-TiO _nano- coated workpiece are compared with the experimental results of the friction and wear performance of the 20Cr round steel substrate in Table 2.

The nano-coating can be prepared on the 4Cr13 mold steel substrate by laser cladding and spraying process to prepare the Ni- _TiO2 coating.

When preparing Ni-TiO2 nano-coating, ultrasonic treatment can be used, which can improve the refinement of metal solidification structure, improve the wear resistance of Ni60A and TiO2 cladding layer, and improve the stability of friction coefficient , The wear mechanism of Ni60A is mainly fatigue wear, and TiO2 is mainly fatigue wear and abrasive wear. The Ni-TiO2 coating subjected to ultrasonic vibration has the best wear resistance and the smallest friction coefficient.

The microstructure, cracks, microhardness and friction and wear properties of the cladding layer were investigated by scanning electron microscope and attached energy spectrometer, X-ray diffractometer, microhardness testing system and multifunctional surface comprehensive performance tester. system analysis. The research results and main conclusions are as follows:

Table 1 The experimental results of the performance comparison between the workpiece with Ni-TiO ₂ nano-coating and the 20Cr round steel substrate:

According to the experimental data, the Ni-TiO2 nano-coating can effectively reduce the porosity of the workpiece surface, improve the bonding strength of the workpiece surface, and greatly increase the microhardness of the workpiece surface.

The experimental results of the friction and wear performance of the Ni-TiO nano _- coating in Table 2 in each embodiment:

group Before test (g) After test (g) Loss (mg) Embodiment one 69.5632 69.5620 1.2 Embodiment two 69.7893 69.7881 1.2 Embodiment three 69.7632 69.7624 0.8 control group 69.3478 69.3347 13.1

It can be seen from Table 2 that the Ni-TiO ₂ nano-coating has excellent wear resistance.

The hardness of the Ni-TiO ₂ coating can reach HRC69 and the thickness of the coating can reach 3 mm through different ratios.

After several tests, it is found that the Ni-TiO ₂ coating has good bonding strength and microstructure density, and the coating density is 7.24g/cm ³ .

This coating material is suitable for a variety of steel materials such as: 20Cr, 12CrNi3A, 5CrMnMo, 5CrNiMo, 4CrMnSiMoV, 5Cr2NiMoVSi, etc.

The nano-coating of the invention is superior to traditional coating materials, has high hardness and good wear resistance, and has great progress compared with traditional alloy materials. Under the same conditions, the wear amount of 20Cr is 13 times that of Ni-TiO ₂ coating, which shows that the Ni-TiO ₂ coating prepared by HVOF has excellent anti-abrasive wear performance. The material contained in the invention has properties such as wear resistance, corrosion resistance and high temperature oxidation resistance, and is an important material for modern machinery manufacturing and repairing of worn parts.

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and what are described in the above-mentioned embodiments and description are only the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention also has various Variations and improvements all fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (2)

1. a Ni-TiO ₂nano coating, is characterized in that: the mass percent of its component and each component is that Ni60A accounts for 71.14%-82.14%, TiO ₂account for 15%-26%, CaF ₂account for 2%, trace element accounts for 0.86%, described trace element comprises Go, Mo, W, Ni.

2. a Ni-TiO ₂the preparation method of nano coating, is characterized in that: comprise the following steps: first adopt dry type comminuting method to obtain Ni60A and TiO ₂nanometer ball, then adopt promoting agent protection method to mix Go, Mo, W, Ni material to obtain nanometer powder, add the auxiliary agent CaF of 2% afterwards ₂, adopt laser melting coating spraying coating process to prepare Ni-TiO afterwards on die steel matrix ₂coating.