Ti-TiN-Zr-ZrN抗冲蚀多层膜的制备、结构及性能

发布时间：2018-08-07 13:08

【摘要】：在航空、航天、能源、机械和冶金等工程领域中,有许多材料(部件)因固体粒子冲蚀磨损导致失效。特别是随着航空航天等高新技术行业的日益发展,传统的结构材料难以满足抗砂粒冲蚀的要求。利用气相沉积技术在工程部件表面制备防护涂层是解决该难题的有效途径之一。国外已有将该气相沉积抗冲蚀硬质薄膜应用于航空发动机压气机部件的报道。但我国在这方面起步晚,研究不系统,特别是表现在对硬质膜层的抗冲蚀行为和失效机理缺乏理论指导;还没完全弄清楚膜层对基体材料疲劳性能的影响等。本文采用阴极电弧离子镀技术制备了Ti-TiN-Zr-ZrN软硬交替抗冲蚀多层膜,并系统研究了多层膜微观结构、残余应力和主要性能评价。得出以下结果:1)在多层膜厚度相当条件下,随着周期数的增加,单一周期变薄,多层膜的表面光洁度和平整度、硬度、结合力及抗砂粒冲刷性能均有明显提升,而残余应力则呈降低趋势;随着钛基与锆基调制比(RTi/TiN:RZr/ZrN)的下降,残余应力呈增大的趋势,结合力也有所下降,硬度略有增加,而抗砂粒冲刷性能变化不明显;随着金属与金属氮化物调制比(RMe:RMeN)的增加,多层膜硬度有所下降,而结合力及抗砂粒冲刷性能变化不明显。本试验Ti-TiN-Zr-ZrN多层膜的优化工艺为每周期约(200~300)nm,金属与金属氮化物调制比RMe:RMe N=1:6,钛基与锆基调制比RTi/TiN:RZr/ZrN=2:1。增加多层膜厚度,残余应力稳定在一定水平,结合力则由于支撑强度的增加而呈上升趋势,当膜厚达到某一值(本试验为7.54μm)后,硬度基本稳定在30GPa以上。2)Ti-TiN-Zr-ZrN多层膜对基体材料有良好的抗砂粒冲蚀保护作用,增加厚度,多层膜抗砂粒冲蚀的能力增强,并且低冲蚀角(30°)保护作用明显优于高冲蚀角(90°)。TC11钛合金的砂粒冲蚀磨损机理属于塑性材料冲蚀机制,即在低冲蚀角条件下主要是砂粒的切削或犁削作用;而在高冲蚀角时则是材料因受砂粒冲击产生塑性变形后导致加工硬化,最终出现疲劳断裂剥落。Ti-TiN-Zr-ZrN软硬交替多层膜的冲蚀磨损机理为在应力集中区或液滴脱落坑萌生裂纹源并沿纵向扩展,当裂纹扩展到金属软层时应力得到缓冲吸收,从而使裂纹扩展方向改变为沿平行于层间界面横向扩展,当裂纹之间扩展相连时,部分膜层便从多层膜中片状分离出来,造成磨损,作者依此建立了软硬交替多层膜冲蚀失效机理模型。3)Ti-Ti N-Zr-ZrN多层膜经300℃和500℃热冲击50次循环后,膜层保持完好,没有裂纹、起泡和剥落,只发生表面氧化而产生颜色加深及颗粒脱落现象,说明多层膜能够有效地保护基体材料。在600℃热冲击10次循环后试样表面均出现膜层因氧化而粉未化和裂纹扩展而分层剥落,膜层已经开始失效。600℃热冲击50次循环后,厚度约10μm的Ti-TiN-Zr-ZrN多层膜已经完全失效,而厚度约20μm的Ti-TiN-Zr-ZrN多层膜仍未完全失效。因此,本试验所制备厚度10μm的Ti-TiN-Zr-ZrN多层膜使用温度≤500℃。4)TC11材料经镀Ti-TiN-Zr-ZrN后疲劳极限由440MPa提高至470MPa,提高了6.8%。应力-疲劳寿命关系(S-N曲线)表明,在应力水平低于570MPa时,多层膜提高了TC11基材疲劳寿命,但当应力水平高于570MPa时,多层膜反而降低了TC11基材的疲劳寿命。对于TC11基材,裂纹源一般萌生于表面缺陷处,且裂纹源数量随应力水平升高而增多,断裂形式是韧性和解理混合型断裂。TC11经镀多层膜后,膜层覆盖基材表面缺陷,在应力水平小于570MPa时,样品只有单一裂纹源,同时软硬交替调制结构的多层膜缓冲了裂纹的扩展,从而提高了试样的的疲劳寿命;在应力水平超过570MPa后,样品有多个裂纹源,多层膜破损严重,从而降低了疲劳寿命,断裂形式也是韧性和解理混合型断裂。5)在同一工艺条件下,基体材料表面粗糙度对多层膜性能的影响很大:降低基体表面粗糙度,有利于改善膜/基结合力、抗冲刷能力和耐腐蚀性能。为了获得良好的膜层综合应用性能,待表面处理目标工件的表面粗糙度必须控制在Ra0.40μm。
[Abstract]:In the fields of aviation, aerospace, energy, machinery and metallurgy, there are many materials (components) caused by erosion and wear of solid particles. Especially with the development of high and new technology industries such as aeronautics and Astronautics, traditional structural materials are difficult to meet the requirement of abrasive erosion. The protective coating is one of the effective ways to solve this problem. There has been a report on the application of the anti erosion hard film to the aero engine compressor components in foreign countries. However, our country is late in this field, and the research is not systematic, especially in the lack of theoretical guidance on the anti erosion behavior and failure mechanism of the hard film; it has not been completely clarified. The effect of the Chu film layer on the fatigue property of the matrix material. In this paper, the Ti-TiN-Zr-ZrN soft and hard alternating anti erosion multilayer film was prepared by cathode arc ion plating technology. The microstructure, residual stress and main performance evaluation of the multilayer film were studied systematically. The following results were obtained: 1) under the condition of the thickness of multilayer film, the number of periods increased. As a period of thinner, the surface smoothness of the multilayer films, the hardness, the hardness, the binding force and the abrasive resistance are obviously improved, while the residual stress is decreasing. With the decrease of the RTi/TiN:RZr/ZrN, the residual stress is increasing, the bonding force also decreases, and the hardness is slightly increased, and the abrasive resistance is scoured. The performance changes are not obvious; with the increase of metal and metal nitride (RMe:RMeN) ratio (RMe:RMeN), the hardness of the multilayer film decreases, and the binding force and the performance change of the abrasive scour are not obvious. The optimization process of the Ti-TiN-Zr-ZrN multilayer film in this experiment is about (200~300) NM, the modulation ratio of the gold and metal nitride is RMe:RMe N=1:6, the titanium and zirconium base modulation With the increase of the thickness of multilayer film, the residual stress is stable at a certain level, and the bonding force is on the rise due to the increase of the support strength. When the thickness of the film reaches a certain value (the test is 7.54 m), the hardness is basically stable above 30GPa.2) Ti-TiN-Zr-ZrN multi layer film has good anti abrasive erosion protection for the matrix material. With the increase of thickness, the ability of multilayer film to resist sand erosion is enhanced, and the protective effect of low erosion angle (30 degree) is obviously better than that of high erosion angle (90 degrees). The erosion mechanism of sand particles of.TC11 titanium alloy belongs to the erosion mechanism of plastic material, that is, the main effect is the cutting or plowing effect of sand under the low erosion angle, while the material is due to the high erosion angle. The plastic deformation of the sand particles is caused by the plastic deformation and causes the hardening. Finally, the mechanism of the erosion and wear of the.Ti-TiN-Zr-ZrN soft and hard alternate multilayer film appears in the stress concentration zone or the drop off pit, and expands along the longitudinal direction. When the crack extends to the metal soft layer, the stress is buffered and absorbed, thus the direction of the crack growth is extended. When the change is transversely extended along the interlayer interface, when the cracks are connected, some films are separated from the multilayer film and cause wear. The author establishes the mechanism model of the erosion failure mechanism of the soft and hard alternating multilayer film.3). After 50 cycles of heat shock at 300 and 500 degrees C, the film remains intact. Cracks, blisters and exfoliation only occur surface oxidation and produce color deepening and particle shedding. It shows that the multilayer film can effectively protect the matrix material. After 10 cycles of heat shock at 600 C, the surface of the specimen appears to be delamination on the surface due to the oxidation of the powder and the crack expansion, and the film has begun to fail at.600 C for 50 cycles. After that, the Ti-TiN-Zr-ZrN multilayer film with a thickness of about 10 m has completely failed, and the Ti-TiN-Zr-ZrN multilayer film with a thickness of about 20 m is still not completely invalid. Therefore, the use temperature of the Ti-TiN-Zr-ZrN multilayer film with thickness of 10 mu m is less than 500 degrees C.4) and the fatigue limit of TC11 material is increased from 440MPa to 470MPa, which increases the stress of 6.8%.. The fatigue life relationship (S-N curve) shows that when the stress level is lower than 570MPa, the multilayer film improves the fatigue life of the TC11 substrate, but when the stress level is higher than the 570MPa, the multilayer film reduces the fatigue life of the TC11 substrate. For the TC11 substrate, the crack source usually sprouts on the surface defects, and the number of crack sources increases with the increase of the stress level. The fracture form is a mixture of ductile and cleavage fracture.TC11 after plating multilayer film, the film covers the surface defects of the substrate. When the stress level is less than 570MPa, the sample has only a single crack source. At the same time, the multilayer film with soft and hard alternating modulation structure cushions the crack growth, thus improving the fatigue life of the specimen, after the stress level exceeds the 570MPa, The sample has multiple crack sources, the multilayer film is badly damaged and the fatigue life is reduced. The fracture form is also the ductile and cleavage mixed type fracture.5. Under the same technological conditions, the surface roughness of the matrix material has a great influence on the properties of the multilayer film: reducing the surface roughness of the matrix, improving the film / base resultant force, anti scour ability and corrosion resistance. The surface roughness of the target workpiece to be treated must be controlled at Ra 0.40 micron in order to obtain good comprehensive application performance of the film.
【学位授予单位】：华南理工大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG174.4

【相似文献】