阅读说明：本技术 一种纳米石墨烯钢基自润滑复合材料及其制备方法 (Nano graphene steel-based self-lubricating composite material and preparation method thereof ) 是由 戴亚春 王海 杨超 骆志高 于 2019-08-12 设计创作，主要内容包括：本发明公开了一种纳米石墨烯钢基自润滑复合材料及其制备方法,涉及材料领域,纳米钢基自润滑复合材料由上到下依次由纳米工作层以及钢基体组成；所述纳米工作层材料的各成分质量百分含量为：纳米石墨烯20～30％,聚四氟乙烯50～60％,聚乙烯10～20％,聚对羟基苯甲酸酯10％；本发明解决了当前钢基自润滑复合材料结合强度低、摩擦磨损性能高、使用寿命短等缺点,提供了一种以钢基与混合纳米材料牢固结合、摩擦磨损性能高、机械强度高、耐磨性能好、耐冲击性好的纳米钢基复合材料。(The invention discloses a nano graphene steel-based self-lubricating composite material and a preparation method thereof, and relates to the field of materials, wherein the nano steel-based self-lubricating composite material sequentially consists of a nano working layer and a steel substrate from top to bottom; the nanometer working layer material comprises the following components in percentage by mass: 20-30% of nano graphene, 50-60% of polytetrafluoroethylene, 10-20% of polyethylene and 10% of poly-p-hydroxybenzoate; the invention solves the defects of low bonding strength, high frictional wear performance, short service life and the like of the current steel-based self-lubricating composite material, and provides the nano steel-based composite material which is firmly bonded by steel base and mixed nano material, and has high frictional wear performance, high mechanical strength, good wear resistance and good impact resistance.)

1. A nanometer graphene steel-based self-lubricating composite material is characterized in that the nanometer steel-based self-lubricating composite material sequentially consists of a nanometer working layer and a steel substrate from top to bottom; the nanometer working layer material comprises the following components in percentage by mass: 20-30% of nano graphene, 50-60% of polytetrafluoroethylene, 10-20% of polyethylene and 10% of poly-p-hydroxybenzoate.

2. The nano graphene steel-based self-lubricating composite material as claimed in claim 1, wherein the nano graphene has a particle size of 20nm, the polytetrafluoroethylene has a particle size of 10 μm, and the polyethylene has a particle size of 30-40 μm; the particle size of the poly-p-hydroxybenzoate is 30-50 mu m, and the steel matrix is subjected to nano treatment.

3. The process for the preparation of nanographene steel-based self-lubricating composite material according to any one of claims 1 to 2, comprising the steps of:

carrying out ultrasonic cleaning on a steel base, then soaking the steel base in a mixed solution of concentrated sulfuric acid and water for 20-30 min, wherein the specific gravity of the concentrated sulfuric acid and the water is 1:1, then placing the steel base in a strong alkali aqueous solution with the mass percentage concentration of 5-10% for alkali cleaning, the soaking time is 20-30 min, the strong alkali aqueous solution is a sodium hydroxide solution, then cleaning the steel base for 5 times by using deionized water, placing the steel base in a vacuum dryer for drying, setting the temperature of the dryer at 90 ℃ for 60min, and carrying out high-energy shot blasting nano treatment on the steel base after drying;

according to the mass percentage, 20-30% of nano graphene, 50-60% of polytetrafluoroethylene, 10-20% of polyethylene and 10% of poly-p-hydroxybenzoate are mixed, the nano working layer material is put into a dryer for drying, and the nano working layer material is uniformly mixed after drying;

the processed nano working layer material and steel base are placed into a pressing sintering furnace, the temperature of the mold is increased to 90 ℃ within 10-15 min to preheat the mold and the nano working layer material, after preheating is finished, the pressure of 70-80 Mpa is adopted to pre-press the nano steel base self-lubricating composite material, then the pressure is unloaded, heating is continued and pressurization is carried out again, after pre-pressing is finished, exhaust treatment is carried out, the temperature is increased to 300 ℃ within 5min, the pressure reaches 7-8 Mpa, pressure relief and exhaust are carried out before the nano working layer enters a molten state, the exhaust action is carried out for three times continuously, the duration time is 15 seconds each time, after exhaust, heating is continued, the pressure is loaded again, the temperature is increased to 300 ℃ within 40min, the pressure is increased to 7-8 Mpa, heat is preserved for 90min, the pressure is unloaded, and the nano steel base self-lubricating composite material is cooled to 80 ℃.

4. The preparation method of the nano graphene steel-based self-lubricating composite material according to claim 3, wherein the steel base is subjected to ultrasonic cleaning for 40-60 min.

5. The preparation method of the nano graphene steel-based self-lubricating composite material according to claim 3, wherein the shot blasting diameter is 0.5mm, the shot blasting speed is 60m/s, and the shot blasting time is 30-60 min.

6. The preparation method of the nano graphene steel-based self-lubricating composite material according to claim 3, wherein the nano working layer comprises the following components in percentage by mass: 20% of nano graphene, 50% of polytetrafluoroethylene, 20% of polyethylene and 10% of poly-p-hydroxybenzoate.

7. The preparation method of the nano graphene steel-based self-lubricating composite material according to claim 3, wherein the nano working layer comprises the following components in percentage by mass: 30% of nano graphene, 50% of polytetrafluoroethylene, 10% of polyethylene and 10% of poly-p-hydroxybenzoate.

8. The method for preparing nano graphene steel-based self-lubricating composite material according to claim 3, wherein the temperature of the dryer is set to 80 ℃ for 2 hours.

Technical Field

The invention relates to the field of materials, in particular to a nano graphene steel-based self-lubricating composite material and a preparation method thereof.

Background

With the rapid development of the times, the worldwide demand for high-tech products with high efficiency, energy conservation and environmental protection is increasing. The friction and wear of the traditional machine parts are reduced by adopting lubricating oil and lubricating grease for lubrication, but under the special working conditions of food, environmental protection, water conservancy and the like, the machine parts are required to be in a working environment with less oil or even no oil in operation, so that better products need to be developed, the machine parts can operate under multiple working conditions, and the environmental noise caused by vibration, jumping and the like during the operation of the machine parts can be reduced. Currently, steel-based self-lubricating composite materials have disadvantages of low bonding strength, high friction coefficient, short service life, etc., so a more effective technology is urgently needed, and the technology needs low friction and wear coefficient, high bonding strength, long service life, simplified production process and low cost.

Disclosure of Invention

The first purpose of the present invention is to overcome the problems of the prior art, and to provide a nano steel-based composite material which is formed by firmly combining a steel base and a mixed nano material, and has the advantages of low friction coefficient, high mechanical strength, good wear resistance and good impact resistance.

The second purpose of the invention is to provide a preparation method of the nanometer steel-based self-lubricating composite material.

In order to achieve the purpose, the invention is realized by the following technical scheme:

the technical scheme of the invention is as follows: a nanometer steel base self-lubricating composite material is composed of a nanometer working layer and a steel base body from top to bottom in sequence; the nanometer working layer material comprises the following components in percentage by mass: 20-30% of nano graphene, 50-60% of polytetrafluoroethylene, 10-20% of polyethylene and 10% of poly-p-hydroxybenzoate;

furthermore, the particle size of the nano graphene is 20nm, the particle size of the polytetrafluoroethylene is 10 microns, the particle size of the polyethylene is 30-40 microns, and the particle size of the poly-p-hydroxybenzoate is 30-50 microns.

Further, the steel substrate is subjected to nano treatment.

The preparation method of the nano steel-based self-lubricating composite material comprises the following steps:

carrying out ultrasonic cleaning on a steel base for 40-60 min, then soaking the steel base in a mixed solution of concentrated sulfuric acid and water for 20-30 min, wherein the specific gravity of the concentrated sulfuric acid and the water is 1:1, then placing the steel base in a strong alkali aqueous solution with the mass percentage concentration of 5-10% for alkali cleaning, wherein the soaking time is 20-30 min, the strong alkali aqueous solution is a sodium hydroxide solution, then cleaning the steel base for 5 times by using deionized water, placing the steel base in a vacuum dryer for drying, setting the temperature of the dryer to be 90 ℃, setting the time to be 60min, carrying out high-energy shot blasting nano treatment on the steel base after drying, wherein the shot blasting diameter is 0.5mm, the shot blasting speed is 60m/s, and the shot blasting time is 30-60 min;

according to the mass percentage, 20-30% of nano graphene, 50-60% of polytetrafluoroethylene, 10-20% of polyethylene and 10% of poly-p-hydroxybenzoate are mixed, the nano working layer material is put into a dryer for drying, the temperature of the dryer is set to 80 ℃, the time is 2 hours, and the nano working layer material is uniformly mixed after the drying is finished;

placing the processed nano working layer material and the steel base into a pressing sintering furnace, raising the temperature of the mold to 90 ℃ within 10min, preheating the mold and the nano working layer material, pre-pressing the nano steel base self-lubricating composite material by adopting the pressure of 70-80 Mpa after preheating is finished, then unloading the pressure, continuing to heat and re-pressurize, exhausting after pre-pressing is finished, raising the temperature to 300 ℃ within 5min, leading the pressure to reach 7-8 Mpa, releasing pressure and exhausting before the nano working layer enters a molten state, wherein the exhausting action is continuous for three times, the duration time is 15 seconds each time, continuing to heat after exhausting, reloading the pressure, raising the temperature to 300 ℃ within 40min, raising the pressure to 7-8 Mpa, preserving the temperature for 90min, finally unloading the pressure, and cooling the nano steel base self-lubricating composite material formed piece to 80 ℃ along with the furnace for demolding.

The invention has the following beneficial effects:

1. the invention solves the defects of low bonding strength, high frictional wear performance, short service life and the like of the current steel-based self-lubricating composite material, and provides the nano steel-based composite material which is firmly bonded by steel base and mixed nano material, and has high frictional wear performance, high mechanical strength, good wear resistance and good impact resistance.

2. The polytetrafluoroethylene is hardly dissolved in any solvent, has strong resistance to various organic solvents, acid and alkali, and has the characteristics of high temperature resistance, low friction coefficient, smaller elastic modulus and larger linear expansion coefficient, so the frictional wear performance of the steel-based self-lubricating composite material can be effectively reduced by adding the polytetrafluoroethylene, and the addition of the polyethylene and the poly-p-hydroxybenzoate can make up the defect of non-adhesiveness between the polytetrafluoroethylene and metal, so that the polytetrafluoroethylene and the metal matrix can be well combined.

3. The nano working layer material comprises the components with the largest mass percentage ratio, is made of polytetrafluoroethylene and other materials with low friction coefficient, is a base material, and is prepared from polyethylene and poly-p-hydroxybenzoate; the poly-p-hydroxybenzoate is a self-lubricating material with an extremely low friction coefficient, which can reach 0.005, even lower than that of lubricating oil or grease.

Detailed Description

In order to more clearly illustrate the technical solution of the present invention, the present invention is further described with reference to the following embodiments: