氮化物涂层的冲蚀磨损模拟研究

发布时间：2018-03-13 14:10

本文选题：氮化物涂层　切入点：冲蚀磨损　出处：《湘潭大学》2012年硕士论文　论文类型：学位论文

【摘要】：冲蚀磨损是现代工业生产中常见的磨损形式之一，是引起材料破坏或者失效的一个重要原因。研究表明使用氮化物涂层材料是提高材料抗冲蚀磨损性能的有效途径之一。本文利用有限元和实验研究的方法，研究了氮化物涂层材料的冲蚀磨损性能，全文主要内容和结论如下：运用压痕断裂力学，对脆性材料冲蚀过程进行了力学分析，建立了脆性材料的体积去除模型；并利用ANSYS/LS-DYNA软件，建立了一种五颗粒的氮化物涂层的冲蚀磨损有限元模型，利用该模型对氮化物涂层的冲蚀磨损性能进行了有限元分析。分析了涂层结构（厚度、过渡层）对氮化物涂层冲蚀磨损的影响，结果表明涂层的冲蚀率随涂层厚度的增加而减小；有过渡层的涂层表现出更好的抗冲蚀磨损性能。分析了涂层的机械性能（硬度H、弹性模量E）对氮化物涂层冲蚀磨损的影响，得出了涂层的冲蚀率随弹性模量的增加而降低，随H/E和H3/E2值的增大而减小，涂层的硬度H与弹性模量E两项力学性能会综合影响涂层的冲蚀磨损性能。分析了基体弹性模量对氮化物涂层冲蚀磨损性能的影响，结果表明基体与涂层的弹性模量相当时，涂层的抗冲蚀性能最好。分析了环境参数（冲蚀角、冲蚀速度）对氮化物涂层冲蚀磨损的影响，结果表明涂层的冲蚀率随冲蚀速度的增大而增大，随冲蚀角的增大而增大，在冲蚀角为90°时冲蚀率达到最大值，涂层表现出典型的脆性材料冲蚀特性。分析了磨料性能（粒径、形状、硬度）对氮化物涂层冲蚀磨损的影响，结果表明涂层冲蚀率随粒径增加而上升；随磨料硬度的增大而增大，当磨料硬度和涂层硬度比值Hp/Ht1时，涂层承受的是硬磨料冲蚀，冲蚀率相对较大；当Hp/Ht1时，涂层承受到的是软磨料冲蚀，冲蚀率相对较小；分析了磨料形状对涂层冲蚀磨损的影响，结果表明六棱柱磨料的冲蚀能力约为球形磨料的4倍。利用冲蚀磨损试验机，对TiAlN涂层冲蚀磨损性能进行了实验研究，实验结果表明，TiAlN涂层的冲蚀率约为硬质合金WC/TiC/Co基体的1/4。利用光学干涉轮廓仪，观测了TiAlN涂层冲蚀表面的宏观形貌，实验结果表明涂层的冲蚀轮廓呈“V”型，且轮廓较为光滑，表现出典型的脆性材料冲蚀特征；利用扫描电镜，观察了TiAlN涂层冲蚀的表面形貌和断面形貌，，分析了TiAlN涂层的冲蚀磨损机理，结果表明TiAlN涂层冲蚀磨损机理主要为脆性疲劳断裂和微切削。
[Abstract]:Erosion wear is one of the common wear forms in modern industrial production. The study shows that the use of nitride coating material is one of the effective ways to improve the erosion resistance of the material. In this paper, the finite element method and the experimental method are used. The erosion and wear properties of nitride coating materials are studied. The main contents and conclusions are as follows:. By using indentation fracture mechanics, the erosion process of brittle materials is analyzed, the volume removal model of brittle materials is established, and a finite element model of erosion and wear of five-particle nitride coatings is established by using ANSYS/LS-DYNA software. The erosion wear performance of nitride coating was analyzed by finite element method. The effect of coating structure (thickness, transition layer) on erosion wear of nitride coating is analyzed. The results show that the erosion rate decreases with the increase of coating thickness, and the coating with transition layer exhibits better erosion wear resistance. The effect of mechanical properties (hardness H, elastic modulus E) on erosion and wear of nitride coating is analyzed. It is concluded that the erosion rate decreases with the increase of elastic modulus and decreases with the increase of H / E and H / E _ 2 ratio. The hardness H and elastic modulus E of the coating will affect the erosive wear performance of the coating. The effect of elastic modulus of substrate on erosion and wear properties of nitride coating was analyzed. The results show that the erosion resistance of nitride coating is the best when the elastic modulus of substrate is equal to that of coating. The effect of environmental parameters (erosion angle, erosion rate) on erosion wear of nitride coating is analyzed. The results show that the erosion rate increases with the increase of erosion velocity and increases with the increase of erosion angle. The erosion rate reaches the maximum when the erosion angle is 90 掳, and the coating exhibits typical erosion characteristics of brittle materials. The effects of abrasive properties (particle size, shape, hardness) on erosion wear of nitride coating were analyzed. The results show that the erosion rate of the coating increases with the increase of particle size, and increases with the increase of abrasive hardness, when the ratio of abrasive hardness to coating hardness is Hp/Ht1. The coating is subjected to hard abrasive erosion, the erosion rate is relatively large; when Hp/Ht1, the coating is subjected to soft abrasive erosion, the erosion rate is relatively small. The effect of abrasive shape on the erosion wear of coating is analyzed. The results show that the erosion ability of hexagonal abrasive is about 4 times that of spherical abrasive. The erosion wear performance of TiAlN coating was studied by using erosion wear tester. The results show that the erosion rate of TiAlN coating is about 1 / 4 of that of cemented carbide WC/TiC/Co substrate. The macroscopic morphology of the erosion surface of TiAlN coating is observed. The experimental results show that the erosion profile of the coating is "V", and the profile is smooth, showing the typical erosion characteristics of brittle materials, and the erosion characteristics of the coating are characterized by SEM, SEM, SEM, SEM, SEM, SEM, SEM, SEM, SEM, SEM. The surface morphology and section morphology of TiAlN coating were observed and the erosion wear mechanism of TiAlN coating was analyzed. The results showed that the erosion wear mechanism of TiAlN coating was mainly brittle fatigue fracture and micro-cutting.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TB306;TH117.1

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