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碳纤维增强聚酰亚胺复合材料表面梯度涂层制备与组织性能研究 总被引:1,自引:0,他引:1
在碳纤维增强聚酰亚胺基体上设计了Ni-Ni/Cr-WC/Co和PI-Ni/Cr-WC/Co两种表面梯度涂层,并对其进行微观组织分析和抗热震性能测试,结果表明,采用化学镀镍和超音速火焰喷涂复合工艺得到的Ni-Ni/Cr-WC/Co梯度涂层结构较为致密,与基体结合较好,涂层经300次热震后无明显变化;采用超音速火焰喷涂得到的PI-Ni/Cr-WC/Co梯度涂层结构疏松,与基体结合力差,涂层经273次热震后完全脱落.镀镍层与基体能够通过机械力和原子力结合,也可以与镍铬合金层通过冶金结合、机械嵌合结合,同时在缓解涂层应力等方面起到重要作用,从而有效提高了梯度涂层的结合强度. 相似文献
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采用高速火焰喷涂技术以及等离子喷涂技术制备了Fe-Ni-B涂层.利用扫描电子显微镜(SEM)、X射线荧光光谱仪(EDX)分析了粉末以及涂层的微观结构、涂层到基体的成分分布.利用X射线衍射(XRD)分析了喷涂态的涂层物相.并对涂层的结合强度及抗热震性能进行了试验研究.研究结果认为:等离子喷涂层组织更为致密,但其热喷涂涂层存在的层状结构也更加明显.熔融液滴在涂层表面的平铺效果都比较好.Fe、Ni元素的分布从涂层到基体基本成均匀分布,避免了局部元素偏析所造成的应力集中.热震后,等离子喷涂涂层中的裂纹分布细小且无规律.高速火焰喷涂涂层裂纹主要集中在涂层与基体结合部位.根据材料抗热震性能的能量理论和弹性理论,等离子喷涂涂层的抗热震能力更强.并且涂层的断裂失效主要产生在结合部位. 相似文献
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采用喷涂法和溶胶-凝胶法相结合的工艺,以FeAlNi混合粉体为过渡层材料在钢基体表面制备了Fe/Al2O3梯度涂层,并对其微观结构与性能进行分析.结果表明:当烧结温度为1220℃时,梯度涂层与钢基体的界面结合强度达到25.3MPa,涂层主要由α-Al2O3,AlFeO3和NiFe2O4等物相组成.Fe/Al2O3梯度涂层与钢基体的结合主要通过吸附与扩散化合两种方式共同起作用.涂层中没有明显的孔洞和平整的界面,且有树枝状组织生成,涂层与钢基体实现良好的结合,这表明涂层成分的梯度化设计能够有效地缓和界面处的应力集中,改善涂层与钢基体的界面结合状态,提高涂层材料的使用性能. 相似文献
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在航空发动机涡轮叶片用碳纤维增强聚酰亚胺(C/PMR15)复合材料表面喷涂WC/Co涂层可以提高其抗氧化耐冲刷性能,采用整体热震法能够评定涂层与基体的结合力.研究了在C/PMR15基体上化学镀镍作为粘结底层对WC/Co喷涂层抗热震性能的影响,并与喷涂PMR15粉末作为过渡层的方法进行了比较.结果表明,在PMR15过渡层上不能得到完整的后续涂层,在化学镀镍粘结底层上可得到连续致密的镍基合金层和WC/Co涂层,镀镍层大幅度提高了基体抗氧化能力,缓和了WC/Co涂层和基体界面位置的热应力,涂层抗热震性提高. 相似文献
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等离子喷涂制备HA/ZrO2复合涂层 总被引:2,自引:0,他引:2
采用等离子喷涂技术,在Ti-6Al-4V基体上成功地制备了羟基磷灰石/氧化锆(HA/ZrO2)复合涂层,对涂层的微观结构、相组成和结合强度进行了研究,并以模拟体液试验评估涂层的生物活性.结果表明,复合涂层具有较为均匀的微观结构.HA/ZrO2复合涂层的结合强度明显高于 HA涂层, HA/60 wt% ZrO2涂层的结合强度高达 28.5MPa,为 HA涂层的 2.2倍.复合涂层在模拟体液中浸泡一段时间后,表面覆盖一层碳酸磷灰石(carbonate-apatite),表明涂层具有良好的生物活性. 相似文献
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设计30wt%~70wt%不同Mo含量的Mo-Ni混合粉末,通过添加少量ZrO2形成梯度复合合金粉末,采用激光直接沉积技术在3Cr2W8V钢板上制备Mo-Ni-ZrO2高温耐磨复合合金梯度涂层。利用金相显微镜、显微硬度计、SEM、能谱仪及XRD等对制备梯度涂层的组织结构、裂纹与气孔消除、相组成及其硬度等进行了研究。结果表明:在Mo-Ni系复合合金梯度涂层中,由于Mo在激光作用下易氧化为MoO_3,MoO_3受热易挥发,在熔池中未能及时逸出,因此,涂层在50wt%Mo梯度层处开始出现裂纹和气孔,其显微硬度平均值为287.29;在Mo-Ni-ZrO2系梯度涂层中,添加ZrO2后,50wt%Mo梯度层处的裂纹和气孔明显减少,该涂层中主相为MoNi及强化相Mo1.24Ni0.76、Ni3Zr,还有少量MoO_3,其显微硬度平均值为477;ZrO2具有良好的消除Mo-Ni高温复合合金梯度涂层裂纹气孔缺陷与增强梯度涂层硬度的作用。 相似文献
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Plasma spraying of zirconia-reinforced hydroxyapatite composite coatings on titanium: Part I Phase, microstructure and bonding strength 总被引:4,自引:0,他引:4
Chang E Chang WJ Wang BC Yang CY 《Journal of materials science. Materials in medicine》1997,8(4):193-200
Plasma-sprayed hydroxyapatite (HA) coatings applied to metal substrates can induce a direct chemical bond with bone and hence achieve biological fixation of the implant. However, the poor bonding strength between HA and substrate has been of concern to orthopaedists. In this study, two submicrometre ZrO2 powders stabilized with both 3 and 8 mol% Y2O3 (TZ3Y and TZ8Y, respectively) were incorporated in a plasma-sprayed HA coating on Ti-6Al-4V substrate to investigate the change in phase, microstructure and bonding strength. The results show that ZrO2 composite coatings contain more unmelted particles and greater porosity. During plasma spraying, ZrO2 reacts with the CaO in HA to form CaZrO3 and accelerates HA decomposition to -TCP and Ca4P2O9. Nevertheless, bonding strength increases with increase of ZrO2 content in the range 0 to 10 wt% studied. The higher Y2O3-containing TZ8Y apparently exerts a greater strengthening effect than the lower Y2O3-containing TZ3Y. 相似文献
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氧化锆陶瓷具有良好的力学性能和生物相容性, 是一种应用前景广阔的硬组织植入体材料。为促进植入体与骨组织形成稳定的骨结合, 本研究利用等离子喷涂制备了氧化锆增韧的锶、硅、氟微量掺杂羟基磷灰石(ZrO2-DHA)涂层, 对涂层物相、形貌以及力学性能和体外生物学性能进行了研究。结果表明, 锶、硅、氟的共掺杂通过成骨分化的信号转导通路提高了羟基磷灰石涂层对成骨细胞的黏附和分化等生物学性能; 不同复合组分的ZrO2-DHA涂层均不同程度地促进了小鼠成骨前体细胞的细胞活力和成骨分化相关基因的表达。在细胞培养的第7 d, DHA含量为70%的ZrO2-DHA涂层(7DHA) Alp和Col-I的相对表达量分别是对照组的约2.8倍和2.3倍; ZrO2-DHA涂层的力学性能随氧化锆组分的增加而增强, DHA涂层和7DHA涂层的硬度和结合强度分别为250.8、313HV和25.1、31.8 MPa; 7DHA涂层中的交织网络结构, 对残余热应力、压应力和拉伸力的承受能力较DHA涂层明显提升, 满足植入体应用需求。 相似文献
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Chang E Chang WJ Wang BC Yang CY 《Journal of materials science. Materials in medicine》1997,8(4):201-211
The change of phase, morphology and bond strength of plasma sprayed hydroxyapatite (HA) coating and ZrO2/HA composite coatings immersed in simulated body fluid (SBF) for various periods of time was studied. X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were used to identify the phase and observe the morphology of the coating surface before and after immersion. In addition, inductively coupled plasma emission spectroscopy (ICP) was used to measure the ion release rate of coatings in SBF for various periods of time. Observation of the morphology by SEM shows that the composite coating with the addition of ZrO2 in HA significantly reduced the dissolution rate of impurity phases in simulated body fluid. The argument was supported by measurement of Ca2+ ion concentration in SBF. During plasma spraying, less OH- ions were lost in a ZrO2-containing composite coating. This factor, together with the reduced effective surface of the ZrO2-containing HA coating, were attributed to the reduced dissolution rate of the composite coatings. All the plasma sprayed coatings degraded after immersion in SBF owing to dissolution of constituents in the coating, however, the addition of ZrO2 in HA improved the bonding strength of HA coating after immersion in SBF. 相似文献
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