晶体氮化碳膜的制备及其涂层刀具切削性能的研究

Carbon nitride has been predicted to having the properties of super-diamond hardness, high chemical inertness and temperature oxidation resistance, etc, which has attracted much attention. Although amorphous carbon nitride films are practical now, but the preparation of crystal films and bulk material is making slow progress. The project is first introduced fluorine-assisted DC arc plasma jet CVD method to prepared high-quality crystal carbon nitride films. In the research of carbon nitride films, we investigate the effects of gas proportion, pressure,its flow ratio, substrate temperature,arc power and other elements on carbon nitride nucleation density, growth rate, film crystalline, selective growth of phase composition, and low-temperature growth etc; we reveal the mechanisms of carbon nitride nucleation, growth; we study the functions of fluorine atoms in carbon nitride deposition process; we reveal the mechanisms of select etching of the fluorine atom,oxygen atom, hydroxyl groups;we study the influences of film composition, microstructure on mechanical properties of coating hardness, friction & wear, and residual stress etc; we adopt nanocrystalline diamond film as a interlayer,we prepare composite coating tools by multi-layer membranes and work over the film-substrate binding mechanism; finally we evaluate and explain the evolutional mechanism of cutting performance. Only the preparation of carbon nitride films especially single-phase thick films achieves success, can the excellent properties be fully demonstrated; furthermore the carbon nitride coated cutting tools may combine the advantages of diamond and cubic boron nitride coated cutting tools without their shortcomings, which will have a broad application prospect.

氮化碳因被预言有超金刚石硬度、高化学惰性和耐高温氧化等性能而备受关注。目前非晶氮化碳膜已经实用化，但晶体膜和体材料的制备进展缓慢。本项目首次采用氟元素辅助直流电弧等离子体喷射CVD法制备高质量晶体氮化碳膜。研究反应气体种类和配比、气压、基底温度和电弧功率等工艺参数对氮化碳膜成核密度、生长速度、膜结晶性、相成分选择生长及低温生长的影响；揭示其成核、生长机理；研究氟原子在低压氮化碳膜沉积过程中的作用；研究氟原子、氧原子和氢氧基等对sp2键的选择刻蚀机制；研究氮化碳膜成分和微结构对涂层硬度、摩擦磨损和残余应力等力学性能的影响；采用纳米金刚石膜作为过渡层，试制由多层膜组成的氮化碳复合涂层刀具并研究膜基结合机制；对其切削性能进行评价并揭示其切削性能的演变机理。晶体氮化碳膜尤其单相厚膜制备成功，才有可能充分展现它的优异性能；其涂层刀具可能兼具金刚石和立方氮化硼刀具长处而无其短处，应用前景广阔。

氮化碳因被预言有超金刚石硬度、高化学惰性和耐高温氧化等性能而备受关注。目前非晶氮化碳膜已经实用化，但晶体膜和体材料的制备进展缓慢。. 本项目首次采用氟元素辅助直流电弧等离子体喷射CVD 法制备高质量晶体氮化碳膜。研究了反应气体种类和配比、气压、基底温度和电弧功率等工艺参数对氮化碳膜成核密度、生长速度、膜结晶性生长的影响；揭示了其成核、生长机理；研究了氟元素在低压氮化碳膜沉积过程中的作用；研究了氟原子等对sp2 键的选择刻蚀机制；研究氮化碳膜成分和微结构对涂层硬度、摩擦磨损等力学性能的影响。. 晶体氮化碳膜具有优异的机械性能，其复合涂层工具优于单一金刚石涂层模具，应用前景广阔。