共查询到20条相似文献,搜索用时 78 毫秒
1.
目的 探究掺杂不同质量分数Y2O3对Al2O3-Y2O3复合涂层微观结构及其力学性能的影响。方法 采用大气等离子喷涂制备Al2O3涂层,以及Y2O3质量分数分别为10%、20%、30%、40%的Al2O3-Y2O3复合涂层。利用SEM、EDS对粉末以及不同涂层的形貌、组织结构、元素分布进行分析。使用XRD表征粉末和涂层的物相。使用显微硬度仪、纳米压痕测试仪和电子万能试验机对涂层的显微硬度、弹性模量以及断裂韧性等力学性能进行测试分析。结果 Al2O3喷涂粉末的物相由α-Al2O3组成,而喷涂得到的Al2O3涂层则由α-Al2O 相似文献
2.
3.
为改善TiO2溅射靶材主要依赖进口的局面,采用大气等离子喷涂技术在不锈钢SUS304平板基体及管状基体上制备了TiO2涂层。利用扫描电子显微镜对涂层形貌进行了观察,并对涂层与基体的结合强度、涂层孔隙率及抗热震性能分别进行了表征。结果表明:粉末熔化及铺展良好,截面可见典型层状结构。涂层与基体以机械结合为主,断裂基本发生在基体与粘结层界面处;涂层的孔隙率较低,同时具有良好的抗热震性能。厚涂层制备过程中,采用循环水冷却方法对不锈钢SUS304管状基体进行冷却,涂层沉积速度快且无开裂和脱落,涂层厚度可达8 mm。通过对冷却装置的改进及喷涂工艺的进一步优化,有望在大尺度管状基体上制备厚涂层以满足溅射蒸镀辊的需要。 相似文献
4.
高速电弧喷涂Fe-TiB2/Al2O3复合涂层的组织及性能 总被引:8,自引:0,他引:8
采用低碳钢包覆0~70%TiB2/Al2O3硬质相的粉芯丝材和高速电弧喷涂(HVAS)原位合成MMC涂层,分析和测试了涂层的组织、相组成及耐磨粒磨损性能.结果表明:涂层的性能由其组织和相组成决定,HVAS的非平衡制造过程在涂层中形成多种相:在Fe基固溶体上存在TiB2、Al2O3、FexB及少量的金属间化合物AlFe3和NiAl;随着TiB2及Al2O3在涂层中体积分数的增加,涂层的耐磨粒磨损性能明显提高,磨损质量损失随陶瓷相体积分数的增加呈线性减少;添加合金元素Ni和Al可降低孔隙率,增加涂层耐磨性.使用HVAS方法制备了含TiB2的高性能耐磨复合陶瓷涂层. 相似文献
5.
采用火焰喷涂和等离子喷涂相结合的方法,在AZ91镁合金表面制备复合CoCrAlY-Al2O3/TiO2涂层,研究了复合涂层的微观形貌、结合强度、耐磨性能和耐腐蚀性能。结果表明,复合喷涂CoCrAlY-Al2O3/TiO2涂层后,AZ91镁合金的耐磨性和耐腐蚀性能得到明显提高。 相似文献
6.
为提高舰船关重部件的耐磨损、抗腐蚀性能,开展了大气等离子喷涂氧化铝复合涂层技术研究。在45钢表面制备Al2O3-40%TiO2陶瓷涂层,通过扫描电子显微镜、显微硬度计、电子天平、摩擦磨损试验机等仪器设备,分析该涂层的显微结构,测其显微硬度、孔隙率等性能,研究其在干摩擦条件下的摩擦磨损性能。结果表明:涂层均匀致密,孔隙率为1.86%,涂层与粘结层之间有明显的倒钩镶嵌结构;Al2O3-40%TiO2涂层的平均硬度为687.2 HV0.1,同时粘结层起到了硬度梯度作用;在干摩擦条件下,45钢主要为严重的黏着磨损,而涂层的磨损主要以层状剥离为主,伴随着少量磨粒磨损,且磨损量低于45钢。在某舰艇主机正时齿轮密封失效部位表面使用Al2O3-40%TiO2涂层,大大提高了正时齿轮的使用寿命,为舰船关重部件的维修与再制造提供了技术支持和理论参考。 相似文献
7.
8.
火焰喷涂EAA/n-SiO2复合涂层热力学性能 总被引:1,自引:0,他引:1
采用火焰喷涂的方法制备了EAA(乙烯-丙烯酸共聚物)及其纳米SiO2(n-SiO2)复合涂层,利用电子拉力机、傅立叶红外光谱仪(FTIR),差示扫描量热仪(DSC)、热重分析仪(TG)对涂层的力学性能、热性能等进行了测试分析.结果表明:在适当的喷涂工艺条件下,物料在火焰喷涂过程中没有发生氧化或降解;DSC、TG分析表明n-SiO2具有明显的成核剂作用,n-SiO2的加入提高了复合涂层的结晶度,加速复合涂层的结晶速度;在n-SiO2含量为2.0%时,复合涂层表现出较好的综合性能,涂层与基体的结合强度达到26.30MPa,涂层自拉伸强度为33.87MPa,较纯涂层提高了30.6%. 相似文献
9.
10.
目的提高C/C复合材料的抗氧化性能。方法采用大气等离子喷涂在C/C复合材料表面制备SiC-Al_2O_3-SiO_2(SAS)复合陶瓷涂层,并选用氧-乙炔在1500℃对涂层进行抗氧化烧蚀性能考核。利用XRD、SEM、EDS等检测分析手段,对团聚粉末和球化粉体以及烧蚀前后涂层的成分及组织进行检测。结果经过等离子球化处理后,三种粉体流动性为90 s/50 g左右,粉末松装密度为1 g/cm~3左右。与团聚的SiC-Al_2O_3-SiO_2粉体相比,粉末流动性提升了20%左右,松装密度提高了20%,更加适宜等离子喷涂工艺。采用球化处理SiC-Al_2O_3-SiO_2粉体制备得到的涂层组织明显优于采用团聚粉体制备的涂层,涂层致密区域明显增大,内部缺陷数量和尺寸减少。在1500℃烧蚀600s后,SiC-36%Al_2O_3-4%SiO_2涂层具有最佳的抗烧蚀效果,涂层整体完整,质量烧蚀率为1.62×10~(-4) g/s。结论 SiC-Al_2O_3-SiO_2体系解决了等离子喷涂制备SiC涂层过程中沉积率低、SiC分解的问题。SiC-Al_2O_3_-SiO_2涂层具有良好的抗氧化烧蚀效果,烧蚀过程中SiO_2和Al_2O_3形成的莫来石相具有良好的高温稳定性、抗热震性以及较低的热膨胀率和氧扩散率,可以进一步提高涂层的抗氧化烧蚀效果。 相似文献
11.
以细雾化铝粉和TiB2颗粒为原料,通过粉末冶金和热轧制制备微米TiB2和纳米Al2O3颗粒增强铝基复合材料。室温时,由于TiB2和Al2O3的综合强化作用,Al2O3/TiB2/Al复合材料的屈服强度和抗拉强度分别为258.7 MPa和279.3 MPa,测试温度升至350℃时,TiB2颗粒的增强效果显著减弱,原位纳米Al2O3颗粒与位错的交互作用使得复合材料的屈服强度和抗拉强度达到98.2MPa和122.5 MPa。经350℃退火1000 h后,由于纳米Al2O3对晶界的钉扎作用抑制晶粒长大,强度和硬度未发生显著的降低。 相似文献
12.
In the present study, mechanically alloyed Al-12Si/TiB2/h-BN composite powder was deposited onto an aluminum substrate by atmospheric plasma spraying. The effect of mechanical alloying (MA) and plasma spray parameters on composite powder and coating structure were investigated. It has been observed that the MA process has a significant effect on the composite powder morphology and reactivity between the selective powders. Results also demonstrate that, at relatively high milling time h-BN decomposes into B and N and forms a solid solution. Also, it has been found that, the relative amount of the in-situ formed AlN through the reaction between h-BN and Al and/or the decomposition of Al-B-N solid solution is independent from the plasma parameters (arc current and secondary gas flow rate). However, spray parameters remarkably affects the coating hardness due to coarsening of Si during the solidification of the coating. 相似文献
13.
In this paper, CeO2 was investigated as an additive for in situ preparation of TiB2/Al composite using an exothermic reaction process via K2TiF6 and KBF4 salts. Experimental results indicated that when 0.5 wt.% CeO2 additive was added, the dispersion of TiB2 particles was improved significantly. Meanwhile, α-Al matrix grain was further refined. Compared with the composite without CeO2, the ultimate tensile strength, yield strength, elastic modulus and tensile elongation increased by 8%, 7%, 26% and 14%, respectively in as-cast condition, and the tensile fracture behavior of the composite with CeO2 belonged to a typical ductile fracture with microvoid coalescence. 相似文献
14.
Effects of sintering additives on microstructure and mechanical properties of TiB2-WC ceramic-metal composite tool materials 总被引:1,自引:0,他引:1
Jinpeng SongChuanzhen Huang Bin ZouHanlian Liu Lin LiuJun Wang 《International Journal of Refractory Metals and Hard Materials》2012,30(1):91-95
TiB2-WC ceramic-metal composite tool materials were fabricated using Co, Ni and (Ni, Mo) as sintering additives by vacuum hot-pressing technique. The microstructure and mechanical properties of the composite were investigated. The composite was analyzed by the observations of scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). The microstructure of TiB2-WC ceramic-metal composites consisted of the fine WC grains and uniform TiB2 grains. The brittle phase of Ni3B4 and a few pores were found in TiB2-WC-Ni ceramic-metal composite. A lot of pores and brittle phases such as W2CoB2 and Co2B were formed in TiB2-WC-Co ceramic-metal composite. The liquid phase of Co was consumed by the reaction which led to the formation of the pores and the coarse grains of TiB2. The pores, brittle phases and coarse grains of TiB2 were harmful to the improvement of the mechanical properties of the composite. The sintering additive of (Ni, Mo) had a significant effect on the density and the mechanical properties of TiB2-WC ceramic-metal composite. The formation of intermetallic compound of MoNi4 inhibited the consumption of liquid phase of (Ni, Mo). The liquid phase of (Ni, Mo) not only inhibited the formation of the pores and the coarse grains of TiB2 but also strengthened the interface energy between WC and TiB2 grains. The grain size was fine and the average relative density of TiB2-WC-(Ni, Mo) ceramic-metal composite reached 99.1%. The flexural strength, fracture toughness and Vickers hardness of TiB2-WC-(Ni, Mo) ceramic-metal composite were 1307.0 ± 121.4 MPa, 8.19 ± 0.29 MPa m1/2 and 22.71 ± 0.82 GPa, respectively. 相似文献
15.
Cagri Tekmen Yoshiki Tsunekawa Masahiro Okumiya 《Surface & coatings technology》2008,202(17):4170-4175
In-situ plasma spraying (IPS) is a promising process to fabricate composite coatings with in-situ formed thermodynamically stable phases. In the present study, mechanically alloyed Al-12Si, B2O3 and TiO2 powder was deposited onto an aluminum substrate using atmospheric plasma spraying (APS). It has been observed that, during the coating process, TiB2 and Al2O3 are in-situ formed through the reaction between starting powders and finely dispersed in hypereutectic Al-Si matrix alloy. Also, obtained results demonstrate that in-situ reaction intensity strongly depends on spray conditions. 相似文献
16.
《稀有金属材料与工程》2012,(Z1):481-486
TiB2-Ni composite powders were prepared by pressurized hydrogen reduction cladding with different proportion of TiB2.The coatings were then prepared by APS.The microstructures and the phase composition of the powders as well as the deposited coatings were analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD).The coatings were tested using a ring-on-disc tribometer from ambient temperature to 300°C.A sprayed Cr3C2-NiCr coating was tested as a reference.The morphologies of the worn surface of the coatings were observed and analyzed.It is found that the TiB2-Ni composite coatings present higher friction coefficient than that of the Cr3C2-NiCr coating at room temperature due to the adhesive wear mechanism,whereas the main wear mechanism of Cr3C2-NiCr coating is rupture and exfoliation.However,at high temperature,the friction coefficient of the TiB2-Ni composite coating decreases as a result of B2O3 solid lubricant,which alleviates the adhesive wear on coatings.Furthermore,the TiB2-Ni composite coating greatly reduces the mass loss of the boron cast iron. 相似文献
17.
WuBian Tian Hideki KitaHideki Hyuga Naoki Kondo 《Journal of Alloys and Compounds》2011,509(5):1819-1823
TiB2-C preforms formed with different compositions and processing parameters were reactively infiltrated by Si melts at 1450 °C to fabricate TiB2-SiC-Si composites. Phase constituent and microstructure of these composites were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The resulting composites are generally composed of TiB2 and reaction-formed β-SiC major phases, together with a quantity of residual Si. Unreacted carbon is detected in the samples with a starting composition of 2TiB2 + 1C formed at higher pressure and in all of the ones at the composition of 1TiB2 + 1C. The distribution of these phases is fairly homogeneous in microstructure. TiB2-SiC-Si composites show good mechanical properties, with representative values of 19.9 GPa in hardness, 395 GPa in elastic modulus, 3.5 MPa m1/2 in fracture toughness and 604 MPa in bending strength. The primary toughening and strengthening mechanism is attributed to the crack deflection of TiB2 particles. 相似文献
18.
Effects of C/B4C ratio on microstructure and property of Fe-based alloy coating reinforced with in situ synthesized TiB2-TiC 下载免费PDF全文
The Fe-based alloy coatings reinforced with in situ synthesized TiB2-TiC were prepared on Q235 steel by reactive plasma cladding using Fe901 alloy, Ti, B4, and graphite(C) powders as raw materials. The effects of C/B4C weight percentage ratio(0-1.38) on the microstructure, microhardness, and wet sand abrasion resistance of the coatings were investigated. The results show that the coatings consist of (Fe, Cr) solid solution, TiC, TiB2, Ti8C5, and Fe3C phases. The decrease of C/B4C ratio is propitious to the formation of TiB2 and Ti8C5. Increasing the C/B4C ratio can help to refine the microstructure of the coatings. However, the microhardness of the middle-upper of the coatings and the wet sand abrasion resistance of coatings degenerate with the increase of C/B4C ratio. The coating exhibits and the wet sand abrasion resistance at C/B4C=0 and its average mass loss rate per unit wear distance is 0.001 2%/m. The change of the wet sand abrasion resistance of the coatings with C/B4C ratio can be mainly attributed to the combined action of the changes of microhardness and the volume percentage of the ceramic reinforcements containing titanium in the coatings. 相似文献
19.