【作者】 郑莉芬；

【导师】 徐玉松；

【作者基本信息】 江苏科技大学 ， 材料学， 2010， 硕士

【摘要】 硬质合金表面涂层刀具结合了基体高强度、高韧性和涂层高硬度、高耐磨性的优点,提高了刀具的耐磨性而不降低基体的韧性。新型涂层材料和涂层工艺的开发方兴未艾,预示着涂层刀具将有巨大发展潜力和广阔应用前景。本文选用自制烧结的YG11C/TaCp硬质合金作为基体,采用磁控反应溅射制备TiN涂层和TiAlN涂层;通过电弧离子镀制备TiN涂层,研究离子镀工艺参数对涂层的性能的影响。经试验,确定了TiN涂层的离子镀的最佳工艺参数:偏压为200V,弧源电流为60A,氮气分压为1Pa。研究表明:上述工艺条件下获得的TiN涂层结构良好,涂层表面光滑平整,组织均匀,具有高硬度和良好的结合强度。按照这个工艺参数制备TiCN涂层和ZrN涂层,并进行了性能对比研究。采用超景深显微镜和扫描电镜对基体材料的金相组织、涂层的表面与界面形貌进行了观察、分析,结合X射线衍射仪对硬质合金基体、TiN涂层、TiCN涂层和ZrN涂层的相分析,可以发现三种涂层都(111)晶面择优取向生长的。涂层刀具经250℃×1h退火后,涂层的性能有所提高;经300℃×1h的退火处理,涂层的晶粒得到细化。对涂层刀具进行界面机理进行分析,并综合切削实验结果,发现ZrN涂层不仅具有较好的结合性能,而且具有最好的耐切削磨损性能。通过系统的滑动摩擦磨损试验,研究了载荷和转速对基体和涂层的摩擦系数的影响,并探究涂层摩擦磨损机理,在高转速高载荷的工作状态下涂层的摩擦系数较低,主要的磨损机理是磨粒磨损,还存在少量的氧化磨损的黏着磨损。基体、TiN涂层、TiCN涂层和ZrN涂层在低载荷低转速的工作状态的摩擦系数比较接近,在高载荷高转速的工作状态下,ZrN的摩擦系数最低,耐磨性能最佳,更适于用作高速切削的刀具的涂层材料。更多还原

【Abstract】 Cemented carbide cutting tools combide the advantages of the substrate high strength and high ductility with high hardness and high wear resisting property of the coating, Increasing cutting tool wear-resistant but not reducing substrate ductility. As new coating materials and coating process is developing in the ascendant, indicating the development of coated tools will have a great potential and broad application prospects.The paper select home-made YG11C/TaCp cemented carbides as substrate, TiN and TiAlN coating were deposited by reactive magnetron sputtering. Craft of depositing TiN by the voltaic arc ionized was introduced, the paper studied how processing parameter influence on property of TiN coating. Then coating/substrate picked up the optimized processing parameter as follow: the minus bias 200V, the N2 pressure component the electric current of arc was 60A. The TiN coating deposited with above processing parameter was slick,well-structural homogeneity, high hardness, and good coating/substrate bonding properties. TiN, TiCN and ZrN coating were deposited by voltaic arc ionized with the same parameter as TiN, so the properties of coatings could be compared. Structural examinations are presented of the applied coatings and their substrate made on the optical microscope, scanning electron microscope and X-Ray diffractomer. TiN, TiCN and ZrN coating were (111) preferred orientation. Annealed coated cutting tool on 250℃and 300℃by 1 hour. The hardness of coating were advanced after annealing on 250℃, crystal grains of coating were refined after annealing 300℃. Analyse interface mechanism of coated cutting tool, we found that ZrN coating was better in bond strength and wear-resisting property.Studied how load and rotational speed influence on friction coefficient of coating, analysed abrasion mechanism by friction experiment. We learned that the friction coefficients were lower under higher load with high rotational speed than under low load with min rotational speed, and the abrasion mechanism was grain-abrasion, as well with little oxidize abrasion and adhesion abrasion. The friction coefficient of Substrate, TiN, TiCN,and ZrN coating were close under low load, the friction coefficient of ZrN was smaller than others, ZrN coating has a good abrasion resistance, as cutting tool, it has more practical significance.更多还原