发动机排气门新型抗高温氧化涂层研究

发布时间：2018-07-02 21:01

  本文选题：发动机排气门 + 耐高温氧化　； 参考：《表面技术》2017年04期

【摘要】：目的提高排气门材料21-4N合金的抗高温氧化腐蚀性能和抗开裂剥落性能,提高排气门的服役性能,延长使用寿命。方法利用两步循环喷雾热解技术在21-4N合金表面制备(Al_2O_3-Y_2O_3)/YSZ层状陶瓷复合涂层,通过扫描电镜和能谱对涂层形貌和成分进行分析,通过循环氧化腐蚀实验评价涂层的抗高温氧化腐蚀性能和抗开裂剥落性能,通过划痕测试来评价涂层的结合强度。结果该层状复合涂层厚度均一、结构致密清晰,在900℃高温循环氧化100 h的实验中,该涂层样品的质量增加量和剥落量分别为0.3025和0.06 mg/cm~2,远低于无涂层21-4N合金的质量增加量和剥落量,具有优异的耐高温氧化腐蚀性能。该复合涂层的膜基结合力达到40 N,远高于21-4N合金表面氧化膜的结合力,能够满足排气门实际应用工况要求。结论采用两步循环喷雾热解技术在21-4N合金表面制备的(Al_2O_3-Y_2O_3)/YSZ层状复合涂层,能够有效提高排气门材料的抗高温氧化腐蚀性能,并具有优异的结合力。
[Abstract]:Aim to improve the high temperature oxidation corrosion resistance and cracking peeling resistance of exhaust valve material 21-4N alloy, improve the service performance of exhaust valve and prolong its service life. Methods A two-step cyclic spray pyrolysis technique was used to prepare the composite coatings on the surface of 21-4N alloy (Al _ s _ 2O _ 3-Y _ 2O _ 3) / YSZ laminated ceramics. The morphology and composition of the coatings were analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The high temperature oxidation corrosion resistance and cracking and spalling resistance of the coatings were evaluated by cyclic oxidation corrosion test. The bonding strength of the coatings was evaluated by scratch test. Results the layer composite coating was homogeneous in thickness and compact in structure, and was oxidized at 900 鈩，

本文编号：2090909