阅读说明：本技术 低钴硬质合金表面金刚石涂层及其制备方法 (Hard alloy in low cobalt surface diamond coating and preparation method thereof ) 是由 张建国 原一高 阮钧 张金江 于 2019-09-16 设计创作，主要内容包括：本发明涉及一种低钴硬质合金表面金刚石涂层及其制备方法,以低钴含量的硬质合金为基体材料沉积金刚石薄膜。利用石墨烯的优异物理性能,提升低钴含量硬质合金的韧性,用于金刚石涂层的基体材料。减少金刚石涂层前的化学预处理时间,避免了长时间的化学反应对基体材料的腐蚀损伤,更好地保持产品的尺寸精度。同时,缓解了钴在金刚石涂层沉积过程中的热扩散作用,改善涂层与基体的附着强度。实现用于金刚石涂层硬质合金基体韧性提升与消除钴元素不利影响的双重效果,为提高金刚石涂层硬质合金产品性能提供了有效方法。(The present invention relates to a kind of hard alloy in low cobalt surface diamond coatings and preparation method thereof, using the hard alloy of low cobalt content as basis material depositing diamond film.Using the superior physical properties of graphene, the toughness of low cobalt content hard alloy, the basis material for diamond coatings are promoted.The chemical pretreatment time before reducing diamond coatings avoids prolonged chemical reaction to the corrosion damage of basis material, preferably keeps the dimensional accuracy of product.Meanwhile thermal diffusion effect of cobalt during Diamond coating deposition is alleviated, improve the adhesive strength of coating and matrix.It realizes the double effects that cobalt element adverse effect is promoted and eliminated for diamond coating for hard alloy matrix toughness, provides effective ways to improve diamond coating for hard alloy properties of product.)

1. a kind of diamond coatings, the coating is using hard alloy as basis material depositing diamond film；

It is characterized in that, by mass percentage, the raw material components of hard alloy include: graphene 0.1~1%, cobalt 2~3%, carbon Change tungsten 97.9-96%.

2. a kind of preparation method of diamond coatings, comprising:

(1) by the graphene of dispersion, cobalt powder and tungsten carbide ball milling mixing, slurry is obtained, is dried in vacuo, sinter molding obtains To hard alloy substrate；

(2) by above-mentioned substrate pretreated, deposition of diamond coatings to get.

3. preparation method according to claim 2, which is characterized in that the graphene dispersed in the step (1) specifically: adopt It is to disperse solution with dehydrated alcohol, the proportion of dehydrated alcohol and graphene is 100mL:(0.1~0.5) g, utilize sonic oscillation point Day labor skill, wherein supersonic frequency is 40KHz；The duty ratio of ultrasound works time is 1:1；The time of sonic oscillation is 4~6h.

4. preparation method according to claim 2, which is characterized in that ball milling mixing specific process parameter in the step (1) Are as follows: for the abrading-ball used for the hard alloy WC-3wt.%Co ball of diameter 5mm, the revolving speed of ball mill is 300~500rpm, ball milling Time is 6~8h.

5. preparation method according to claim 2, which is characterized in that vacuum drying in the step (1) are as follows: drying process In, heating temperature is 90~100 DEG C, until in slurry without visible liquid when, stop heating, spontaneously dry 2~3h, dry overall process In, the holding indoor pressure of vacuum is 10000~15000Pa.

6. preparation method according to claim 2, which is characterized in that the temperature of sinter molding is 1380 in the step (1) DEG C, pressure 40MPa.

7. preparation method according to claim 2, which is characterized in that pretreatment in the step (2) specifically: soak matrix It not in alkaline solution treatment 10min, cleans, drying, then the matrix after alkali process is immersed in acid solution natural reaction 10s, clean, Drying；It is ground, is cleaned with the mixed solution of bortz powder and glycerine, drying；Wherein lye is the potassium ferricyanide: potassium hydroxide: Water=1g:1g:10mL；Acid solution is hydrochloric acid: hydrogen peroxide=1mL:4mL.

8. preparation method according to claim 2, which is characterized in that deposition in the step (2) specifically: use heated filament It learns vapor deposition method pretreated matrix is placed in chemical vapor depsotition equipment, the vacuum chamber pressure to equipment reaches After 5Pa or less, input reaction 10~20sccm of working gas methane flow, 1000~2000sccm of hydrogen flowing quantity adjust reaction Pressure is 2000~4000Pa, and coat deposition time is 6~10h.

9. a kind of diamond coatings of claim 2 the method preparation.

10. a kind of application of diamond coatings described in claim 1.

Technical field

The invention belongs to diamond coatings and its preparation field, in particular to a kind of hard alloy in low cobalt surface diamond applies Layer and preparation method thereof.

Background technique

High rigidity, high-wearing feature, high heat conductance, low-friction coefficient and the good chemical inertness of diamond coatings etc. are many Excellent properties, so that it is widely applied in tool and mould field.In hard alloy tool and mould surface deposition of diamond coatings, not only may be used To increase substantially the service life of tool and mould, moreover it is possible to improve the machined surface quality of workpiece.

The balance of basis material hardness and toughness in order to balance, the hard alloy substrate amount containing cobalt that diamond coatings are selected are logical It is often 6wt.%~8wt.%.However, in order to eliminate the urging during Diamond coating deposition of the cobalt element in basis material Graphitizing before preparing diamond coatings, and must carry out " cobalt is removed in chemical attack " pretreatment to hard alloy substrate. The amount containing cobalt of matrix is higher, and the time of chemical attack is longer.While " removing cobalt ", the carbonization tungsten structure in matrix is brought not Evitable damage, to influence the performance of basis material.So that the performance of diamond coatings product can not achieve the desired results.

Through the patent retrieval discovery to the prior art, Chinese Patent Application No. 201510673007.4 and 03117958.4 is mentioned Out using the gradient hard alloy of the poor cobalt of superficial layer as basis material, diamond coatings are prepared, to solve cobalt element to gold The influence of hard rock coating deposition, combines the intensity and toughness of matrix.But the rich cobalt layers of gradient hard alloy matrix core During Diamond coating deposition, since matrix is heated, what the thermal diffusion effect of cobalt still can cause diamond coatings urges stone Inkization and reduction film base adhesive strength.

Summary of the invention

Technical problem to be solved by the invention is to provide a kind of hard alloy substrate toughening diamond coatings and its preparations Method, overcoming in the prior art is 6wt.%~8wt.% applied to amount containing cobalt in the hard alloy of diamond coatings, in order to obtain Preferable pretreating effect, need to carry out the chemical pretreatment of long period, while " removing cobalt ", also damaged the knot of matrix Structure performance.In addition, the higher cobalt content of intrinsic silicon during Diamond coating deposition, has stronger thermal diffusion to act on, lead The technical problem for causing diamond coatings low with the bond strength of matrix.Low cobalt content hard alloy substrate toughening deposits in the present invention Diamond coatings.

A kind of diamond coatings of the invention, the coating is using hard alloy as basis material depositing diamond film；

It is characterized in that, by mass percentage, the raw material components of hard alloy include: graphene (powder) 0.1wt.%~ 1wt.%, cobalt 2wt.%~3wt.%, tungsten carbide (powder) 97.9wt.%-96wt.%.

A kind of preparation method of diamond coatings of the invention, comprising:

(1) by the graphene of dispersion, cobalt powder and tungsten carbide powder ball milling mixing, slurry is obtained, is dried in vacuo, matrix is burnt Form type, obtains carbide matrix material；

(2) by above-mentioned substrate pretreated, deposition of diamond coatings to get.

The preferred embodiment of above-mentioned preparation method is as follows:

The graphene dispersed in the step (1) specifically: use dehydrated alcohol to disperse solution, dehydrated alcohol and graphite The proportion of alkene is 100mL:(0.1~0.5) g, using sonic oscillation dispersing technology, wherein supersonic frequency is 40KHz；Ultrasound works The duty ratio of time is 1:1；The time of sonic oscillation is 4~6h.

Ball milling mixing specific process parameter in the step (1) are as follows: the abrading-ball used is the hard alloy WC- of diameter 5mm 3wt.%Co ball, the revolving speed of ball mill are 300~500rpm, and Ball-milling Time is 6~8h；Wherein dehydrated alcohol: powder: abrading-ball Proportion are as follows: (1~2) mL:1g:(7~10) g.

Vacuum drying in the step (1) are as follows: it by the slurry after mixing, is placed in a vacuum drying oven, is dried, In drying process, heating temperature is 90~100 DEG C, until in slurry without visible liquid when, stop heating (close heating function), from 2~3h is so dried, is dried in overall process, the holding indoor pressure of vacuum is 10000~15000Pa.

Sinter molding in the step (1): by the powder after drying, after being pressed into the shape of design requirement, using vacuum Pressure sintering processes, sinter molding, temperature be 1380 DEG C, pressure 40MPa.

Pretreatment in the step (2) specifically: matrix is immersed in alkaline solution treatment 10min, is cleaned, drying, then will Matrix after alkali process is immersed in acid solution natural reaction 10s, cleans, drying；With the mixed solution of bortz powder and glycerine Grinding is cleaned, drying；Wherein lye is the potassium ferricyanide: potassium hydroxide: water=1g:1g:10mL；Acid solution is hydrochloric acid: hydrogen peroxide =1mL:4mL.

Deposition in the step (2) specifically: set pretreated matrix using hot-wire chemical gas-phase deposition method In chemical vapor depsotition equipment, after the vacuum chamber pressure of equipment reaches 5Pa or less, input reaction working gas methane flow 10~20sccm, 1000~2000sccm of hydrogen flowing quantity, adjusting reaction pressure are 2000~4000Pa, coat deposition time 6 ~10h.The present invention provides a kind of diamond coatings of the method preparation.

The present invention provides a kind of application of diamond coatings.

Beneficial effect

(1) it is unfavorable to coating to solve high cobalt content in the hard alloy substrate of diamond coatings in the prior art by the present invention The problem of can not coordinating with matrix strength toughness is influenced, a kind of low cobalt content carbide matrix for diamond coatings is provided Body toughening technique and coating production；

(2) using excellent characteristics such as graphene intensity height, good toughness, the toughness of low cobalt content hard alloy substrate is improved, The composition of graphene is carbon, does not introduce other impurities element in hard alloy preparation process, so that the composition of hard alloy is not It will receive influence；

(3) when the hard alloy of low cobalt content is used for diamond coatings, the chemical attack time of pretreatment stage " alkali+acid " It reduces, avoids long-time chemical attack to the adverse effect of cemented carbide material performance and to finished work-piece dimensional accuracy It influences, while also avoiding high cobalt content inside conventional rigid alloy to lead to coating quality and film in the thermal diffusion of deposition process The problem of film-substrate binding strength difference；

(4) present invention utilizes the superior physical properties of graphene, promotes the toughness of low cobalt content hard alloy, is used for Buddha's warrior attendant The basis material of stone coating, the chemical pretreatment time before reducing diamond coatings avoid prolonged chemical reaction to base The corrosion damage of body material preferably keeps the dimensional accuracy of product.Meanwhile cobalt is alleviated during Diamond coating deposition Thermal diffusion effect, improve coating and matrix adhesive strength, realize for diamond coating for hard alloy matrix toughness promoted With the double effects for eliminating cobalt element adverse effect, efficacious prescriptions have been provided to improve diamond coating for hard alloy properties of product Method.

Detailed description of the invention

Fig. 1 is the impression shape of ordinary rigid alloy (6wt.%Co) matrix surface diamond coatings obtained in comparative example Looks；

Fig. 2 is enhancing low cobalt content (3wt.%Co) hard alloy (the 0.3wt.% graphite of graphene made from embodiment 1 Alkene) matrix surface diamond coatings vickers indentation.

Fig. 3 is enhancing low cobalt content (3wt.%Co) hard alloy (the 0.5wt.% graphite of graphene made from embodiment 2 Alkene) matrix surface diamond coatings vickers indentation.

Specific embodiment

Present invention will be further explained below with reference to specific examples.It should be understood that these embodiments are merely to illustrate the present invention Rather than it limits the scope of the invention.In addition, it should also be understood that, after reading the content taught by the present invention, those skilled in the art Member can make various changes or modifications the present invention, and such equivalent forms equally fall within the application the appended claims and limited Range.