等离子喷涂TiC—Ni—Mo金属陶瓷涂层结构与性能的研究

在４５钢基材上用等离子喷涂方法制备了ＴｉＣ－Ｎｉ－Ｍｏ金属陶瓷涂层,对涂层进行了性能试验,ＳＥＭ分析及ＸＲＤ分析,结果表明,等离子喷涂ＴｉＣ－Ｎｉ－Ｍｏ金属陶瓷涂层组织是均匀的,涂层硬度达到９０ＨＲＡ。涂层经频率为１６次／ｍｉｎ,６０ｍｉｎ落球冲击试验后,显微镜下未见到任何剥离痕迹或裂纹,经比较试验,该涂层的结合强度和韧性优于同样基材上等离子喷涂的ＺｒＯ２陶瓷梯度涂层。     

超音速火焰喷涂碳化物金属陶瓷涂层冲蚀磨损性能

采用超音速火焰喷涂技术喷涂不同工艺的两种粉末,得到Cr3C2-25NiCr和WC-12Co涂层;对涂层的冲蚀磨损性能进行了测试;采用扫描电镜对原始粉末以及冲蚀前后涂层的组织形貌进行了观察。结果表明,团聚烧结粉制备的涂层组织较致密。粘结相含量较多的涂层,其冲蚀磨损性能较差;致密度较高的涂层,其冲蚀磨损性能较好。     

等离子喷涂制备Co基TiC金属陶瓷涂层的微观形貌及耐高温腐蚀性能

采用等离子喷涂技术在GH586合金表面制备了一层Co基TiC金属陶瓷涂层。研究了TiC含量对Co基TiC金属陶瓷涂层显微组织及耐高温腐蚀性能的影响。结果表明:TiC陶瓷颗粒与Co基粉体有良好的润湿性,呈现相互包裹的结构,涂层结合紧密无缺陷;TiC的加入,提高了Co基TiC金属陶瓷涂层的耐磨性,但当TiC含量过高时,团聚现象严重,导致涂层的耐高温腐蚀性能降低;TiC质量分数为10%时,TiC颗粒在涂层中分布较为均匀,此时涂层的耐高温腐蚀性能和耐磨性都较优。     

反应爆炸喷涂制备TiC／Fe-Ni金属陶瓷复合涂层

以钛铁粉、羰基镍粉和碳的前驱体(蔗糖)为原料,通过前驱体碳化复合技术制备Ti-Fe-Ni-C系反应热喷涂粉末,并通过爆炸喷涂技术原位合成并沉积TiC/Fe-Ni金属陶瓷复合涂层;利用XRD、SEM和EDS研究喷涂复合粉末和涂层的相组成、显微结构.结果表明:采用前驱体碳化复合技术制备的Ti-Fe-Ni-C反应喷涂复合粉末粒度均匀;所制备的TiC/Fe-Ni复合涂层由不同含量TiC颗粒分布于金属基体内部而形成的复合片层叠加而成,基体主要是(Fe,Ni)固溶体;TiC颗粒大致呈球形,粒度为纳米级;复合涂层的平均显微硬度HV0.2为18.9 GPa.     

金属陶瓷涂层高性能耐磨件的研制

采用高速火焰（ＨＶＡＦ）喷涂工艺制备金属碳化物陶瓷涂层，使拉丝轮圈的耐磨性能大幅度提高。介绍了涂层工艺和产品标准，并研讨有关问题。     

反应等离子喷涂TiC陶瓷增强金属复合涂层组织性能

采用前驱体碳化复合技术利用钛铁粉为原料制备Ti-Fe-Ni-C和Ti-Fe-C系粉末,并通过反应等离子喷涂技术(RPs)原位合成并沉积了Tic/Fe-Ni和TiC/Fe金属陶瓷复合涂层.利用XRD、SEM和EDS研究了复合粉末和不同基体涂层的成分、组织结构,测量了2种涂层的显微硬度和磨损量.结果表明:采用前驱体碳化复合技术制备的反应喷涂复合粉末粒度均匀、无有害相生成;制备的复合涂层由不同TiC颗粒含量的片层组织叠加而成;TiC颗粒大致呈球形,基体主要为Fe及Fe、Ni固溶体.Tic/Fe-Ni涂层较TiC/Fe涂层组织更加均匀、致密,且具有较高的显微硬度和较好的耐磨性.     

H13钢表面电火花沉积WC-Ni基金属陶瓷涂层微观组织及摩擦磨损性能

为了提高H13钢表面性能,延长其使用寿命,采用电火花沉积工艺在H13钢基体上制备了WC-Ni基金属陶瓷涂层,并分别以Ni和Mo作为过渡层制备了复合涂层.利用XRD、SEM、EDS、显微硬度计和摩擦磨损试验机分析了涂层的物相、微观组织、显微硬度和摩擦磨损性能.结果表明,WC-Ni涂层表面由溅射状沉积斑点堆积而成,横截面分为涂层区、过渡层和基体3个区域,WC硬质相弥散分布于涂层内.Ni/WC-Ni复合涂层的表面较为光滑平整,Ni过渡层的引入并未改变涂层的物相,界面处WC硬质相异常长大.Mo/WC-Ni复合涂层表面存在微细裂纹,且生成了新相Fe9.7Mo0.3.复合涂层的硬度均高于WC-Ni涂层,复合涂层的摩擦系数和磨损失重均低于基体与WC-Ni涂层,Mo/WC-Ni复合涂层具有更好的耐磨性.     

等离子喷涂纳米ZrO_2涂层的摩擦磨损性能研究

采用等离子喷涂法在钛合金(TC4)基体上制备纳米陶瓷涂层。研究了烧结型陶瓷、纳米陶瓷和纳米球化陶瓷涂层的微动摩擦磨损性能。结果表明:在微动磨损滑移区、不同载荷水平下,三种涂层均呈现相同的耐磨性规律,耐磨性能由好到差的顺序为纳米球化陶瓷纳米陶瓷烧结型陶瓷。     

CeO2对等离子喷涂Ti-Al/WC金属陶瓷复合涂层组织和摩擦学性能的影响

通过等离子喷涂方法在45钢基体上制备添加不同含量稀土氧化物CeO_2的Ti-Al/WC金属陶瓷复合涂层,利用扫描电镜和能谱仪等检测设备探究CeO_2对涂层组织及摩擦学性能的影响。结果表明:CeO_2细化了等离子喷涂涂层的层片状结构,改善了其结合性;添加不同含量CeO_2的涂层耐磨性均高于未添加涂层,其中2%的添加量,涂层表现出更加优良的性能; CeO_2的加入改变了涂层的磨损机理,由黏着磨损为主过渡为磨粒磨损为主,提高了涂层强度,减轻了磨损程度。     

热处理对铁基TiC复合涂层的组织及磨损性能的影响

采用电弧喷涂技术在低碳钢Q235基体上制备铁基TiC复合涂层,利用箱式电阻炉对涂层进行400、500、600、700和800℃的热处理,研究其对铁基TiC复合涂层组织和磨粒磨损性能的影响。利用光学显微镜、扫描电子显微镜(SEM)和X射线衍射仪(XRD)对涂层的显微组织结构、磨损表面和相组成进了分析和研究。结果表明:热处理对Fe-TiC复合涂层的组织、硬度和耐磨性有显著影响,500~700℃热处理能够改善电弧喷涂铁基TiC涂层的耐磨性;500℃热处理后的涂层具有较好的耐磨损性能;随着热处理温度的增加,涂层中出现更多的氧化物相,涂层的磨损机理由犁沟切削和脆性脱落逐步转化为以脆性脱落为主。     

Influence of Mo on the microstructure and mechanical properties of TiC-based cermets

The microstructures and mechanics properties of TiC-based cermets composed of TiC, WC, Ni, Co, Mo, and Cr₃C₂ were investigated. The results show that Mo has a great effect on the sintering densification, microstructures, and mechanical properties. The microstructures and distribution of Mo and Ti in the TiC-based cermets were analyzed. It was indicated that a new phase with Ti, Mo, W, and C was formed on the rim of (Ti,W)C grains by means of an addition of Mo into the TiC-based cermets. The new phase with a surrounding structure was of great aid to improve the wettability of the liquid phase on the solid phase surface of TiC, decrease the porosity and refine the grains of the hard phase, which gave rise to the increase in strength and hardness. The properties of the TiC-based cermets could be further improved to some extent by adding WC, Cr₂C₃, and Co.     

钼对钴基合金激光熔覆层组织与耐磨性的影响

利用激光熔覆技术在低碳钢基体表面制备了钴基合金涂层.利用金相显微镜(OP)、扫描电镜(SEM)及x射线衍射仪(XRD)等研究了不同Mo元素含量的钴基合金涂层的组织结构;通过采用显微硬度试验、滑动磨损试验等方法进行性能测试.结果表明,含5.4%Mo的合金熔覆层主要组成相为γ-Co,Cr_(23)C_6,而含28%Mo的合金涂层主要相组成为γ-Co,Cr_(23)C_6,Co_3Mo_2Si_2和NiCor等相;含5.4%Mo涂层的组织主要为柱状生长树枝晶;含28%Mo单道涂层的结合区为紊乱的粗大树枝晶,中部为向上生长的细小的树枝晶,表层为细小的等轴晶,多道搭接涂层组织为细小的等轴晶;含28%Mo涂层的显微硬度可达800 HV以上,比含5.4%Mo涂层的硬度提高了一倍;耐磨性也有不同程度的提高.

Abstract：

Co-based alloy coatings with different Mo content (5.4% and 28 % ) on the surface of low carbon steel were prepared by laser cladding. The microstructure and phases composition of the coatings were investigated by means of optical microscope (OP), scanning electron microscope (SEM) and X-ray diffraction instrument (XRD). Microhardness and sliding wear resistance of the coatings were also tested. The results indicated that the main phases in Co-based alloy coatings with 5.4%Mo were γ-Co and Cr_(23) C_6. Another two phases of Co_3 Mo_2 Si and NiCoCr were identified in Co-based alloy coatings with 28% Mo. Directional dendrite was observed in Co-based alloy coatings with 5.4% Mo. Unidirectional dendrite at the interface, followed by fine dendrite at the central zone and equiaxed grain near top surface were found in Co-based alloy single coatings with 28% Mo, and almost all fine equiaxed grains appear in the multi-track coatings. The microhardness of Co-bascd alloy coatings with 28% Mo reaches up to 800 HV, which was 2 times of that of Co-based alloy coatings with 5.4% Mo. The sliding wear resistance was also improved.     

多元陶瓷复合相显微组织对耐磨性能的影响

采用等离子熔覆技术制备了四种不同铬含量的Fe-Cr-B-C堆焊合金.借助OM,SEM和XRD等分析手段对合金组织和陶瓷相形貌进行分析.结果表明,熔覆层的微观组织由初生奥氏体＋共晶组织组成,合金陶瓷相由BC4＋Cr2B＋M7C3＋M23C6＋M23（C,B）6组成,硼化物呈层片状、菊花状等形态分布,陶瓷相数量随Cr元素含量的增大而增多.研究了Cr元素含量对熔覆层耐磨粒磨损性能的影响规律,熔覆层的耐磨性随着Cr元素含量的增加而提高,当Cr元素含量达到15.9%时,大量硼化物等陶瓷相弥散分布在基体中,构成良好的耐磨骨架;初生奥氏体组织均匀分布提高硬质相与基体界面的结合强度,因此其熔覆层具有最佳的耐磨性.     

TiC含量对激光合金化层组织和耐磨性的影响

以亚微米级TiC和WC作为陶瓷硬质相,自制的合金粉末作为粘结相,采用激光表面合金化技术在球墨铸铁表面制备出高硬度、耐磨的合金化层.利用扫描电子显微镜(SEM)、EDAX能谱仪(EDS)、X射线衍射仪(XRD)等分析测试手段对不同TiC含量下的合金化层的显微组织和物相构成进行了分析,并对合金化层进行了硬度和摩擦磨损性能测试.结果表明,随着涂料中TiC含量的增加,合金化层中碳化物硬质强化相逐渐增多,合金化层的硬度和耐磨性也逐渐提高.当TiC含量为40%时,合金化层的性能较好,平均显微硬度可达1097 HV0.2,其磨损量仅为基材球墨铸铁的1/9.     

感应加热对AlCoCrFeNi-Cu复合涂层组织及耐磨性的影响

采用氧-乙炔火焰喷涂在40Cr钢表面制备了AlCoCrFeNi-Cu复合涂层,为了进一步降低涂层的孔隙率,提高涂层的硬度和耐磨性,将所得涂层进行感应加热处理,研究了感应加热工艺对涂层相组成、微观形貌、显微硬度和摩擦磨损性能的影响.结果 表明:经过感应加热后,涂层中高熵合金没有发生氧化和分解,涂层的孔隙率最高下降了41....     

工业纯铜陶瓷/渗铝复合涂层制备及耐磨性

利用热化学反应法和化学热处理在工业纯铜上同时制备陶瓷/渗铝复合涂层。与热化学反应陶瓷涂层相比,复合涂层的致密度、结合强度均优于热化学反应陶瓷涂层。封孔后耐磨粒磨损性能是基体的4.05倍,耐粘着磨损(干摩/油摩)性能分别为基体的3.67倍和10.43倍。     

Adhesion and dynamic impact wear of nanocomposite TiC-based coatings prepared by DCMS and HiPIMS

Nanocomposite nc-TiC/a-C:H coatings exhibit a unique combination of mechanical properties such as high hardness, and low friction and wear. These physical and mechanical properties make those coatings attractive for application in industry. However, the properties of the whole coating/substrate system such as adhesion of the coating to substrate and its response on repeated impact loading known such as dynamic impact wear are also important for industrial applications. Thus, this paper is focused on the adhesion and the dynamic impact wear of nc-TiC/a-C:H coatings prepared by the hybrid PVD-PECVD process. Two series of nc-TiC/a-C:H coatings with a different amount of carbon were deposited onto commonly used industrial cemented tungsten carbide substrates using DC magnetron sputtering (DCMS) and the high power impulse magnetron sputtering (HiPIMS) of a titanium target in argon and acetylene mixture atmosphere. Both series of coatings were analysed using a scratch test and dynamic impact tester with an impact load of 600 N. The HiPIMS prepared coatings exhibited lower thickness and lower thicknesses of the Ti adhesive interlayers between the substrates and coatings than the DCMS prepared coatings. Thus, the adhesion and the impact wear of both series were discussed separately. These properties were discussed with respect to the coating microstructure, phase composition and mechanical properties such as the hardness H, the effective elastic modulus E, and the H/E and H³/E² ratios. The scratch adhesion of coatings depended on the H³/E² ratio and coating microstructure, hardness and surface roughness. The impact wear of the nc-TiC/a-C:H coatings depended on the H/E ratio and coating microstructure.     

CeO2对碳硼共渗层组织及耐磨性的影响

探讨了CeO2对碳硼共渗层组织及性能的影响,利用金相显微镜、扫描电镜、能谱仪、X射线衍射仪分析了共渗层的组织形貌、元素含量及分布、表面相组成,利用显微硬度计、摩擦磨损试验机测定了共渗层的硬度变化和摩擦磨损特性.结果表明,加入CeO2的硼化物层和增碳层均比未加入CeO2的硼化物层和增碳层厚,其硼化物层的厚度提高大约33%,而且厚度相对比较均匀.CeO<2的加入使硼化物层的齿形更连续,致密性更好,使共渗层的显微硬度比未加入CeO2的显微硬度平均提高大约21%.CeO2的加入使共渗层与基体之间形成富碳过渡层,经淬火后形成了一层硬度较高且不易产生塑变的支撑层,有效地提高了共渗层的耐磨性,其耐磨性比未加入CeO2的耐磨性提高大约37%.     

Effect of molybdenum on the microstructure and corrosive wear resistance of laser clad Ni-based coatings

Five kinds of Ni-based coatings with 0 wt%, 2.5 wt%, 5.0 wt%,7.5wt% and 10.0wt% molybdenum were prepared on 45CrNi steel plates by using laser cladding technique. The effect of Mo on the microstructure of Ni-based coatings was investigated by using scanning electron microscopy. The corrosive wear resistance and the corrosion resistance of five coatings were tested. The results show that the corrosive wear resistance of the coating with 5.0wt% Mo is better than those of other coatings. During the corrosive wear process, the corrosion and wear effects are combined. The corrosive wear resistance is closely related to the microstructure of the coating.     

Influence of titanium nitride addition on the microstructure and mechanical properties of TiC-based cermets

In this paper, the TiC-based cermets with addition of TiN were fabricated by a conventional powder metallurgy process. The titanium nitride (TiN) and titanium carbide (TiC) used as starting powders have been synthesized by the self-propagating high temperature synthesis (SHS) method. This exothermic reaction, easy to process, allows to obtain fine and original powders from low-cost raw materials. Cermets obtained by sintering powders of TiC and Mo₂C with nickel binder phase are investigated. The effect of TiN adding on the microstructure and the mechanical properties of these composites are studied. Microstructures have been observed by scanning electron microscopy (SEM). Room temperature mechanical properties such as Young’s modulus, fracture toughness and microhardness have been measured and related to morphology and chemical composition of the samples. Tribological experiments were also performed and the friction coefficient of a cermet containing titanium nitride was compared with that of other hard materials. The SHS starting powders used present some particularities, as it was shown in a previous study [Matériaux à base de carbures et nitrures, pour coupe et usure, obtenus à partir de poudre SHS, PhD Thesis, INSA Lyon, 2004]. The purpose of this work is to show that results concerning the impact of TiN addition on microstructure and mechanical properties obtained on bulk specimens, from these original starting powders, are similar to the ones obtained on alloys from commercial starting powders.