| 摘要: |
| 为开发在高温环境、大温差条件下具有热应力缓和功能的新型耐蚀涂层，应用Nd:YAG激光在钛合金表面制备了钛基FGM和NFGM，观察了微观组织，测量了显微硬度变化规律以及FGM和Ti600基体的耐腐蚀性能。结果表明，原位合成的TiC球状增强体弥散分布在FGM中，主要呈3种不同的形态：粗大的或不完整的树枝晶，相对较为细小的等轴或近似等轴晶和细小短纤维状晶。由于快速凝固的微观结构和大量弥散均匀分布的TiC增强相，FGM和NFGM显微硬度值均较高，平均约为1450 HV，是Ti600基材(310 HV)的4.5～5倍。且随梯度层中TiC增强相含量的减少，FGM显微硬度值连续梯度降低。Ti600基体和FGM耐蚀性均较好；极化电位较低；自腐蚀电流密度小，在10-8A·cm-2范围。FGM耐蚀性能较Ti600得到提高，腐蚀电流密度和电阻值分别为Ti600的0.72和1.31倍。 |
| 关键词: 钛基梯度功能 涂层 微观组织 显微硬度 腐蚀 |
| DOI： |
| 分类号: |
| 基金项目:国家博士后科学基金（20060391000） |
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| Microstructure and Corrosion Behavior of TiMatrix Functional Gradient Layer |
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CUI Ai–yong, HU Fang–you, HUI Li, PENG Xin1,2,3
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1. Aeronautical Mechanical Institute, Naval Aeronautical Engineering College, Qingdao Branch, Qingdao Shandong 266041;2. Engineering College, Shenyang Aeronautical Engineering University, Shenyang 110034;3. Chemistry and Chemical Engineering College, Ocean University of China, Qingdao Shandong 266100
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| Abstract: |
| To development a new corrosion resistant layer with alleviating thermal stress function under hyperthermal and big difference in temperature conditions, research of producing Timatrix FGM and NFGM on Ti600 substrates by pulsed Nd:YAG had been carried out. The microstructures and microhardness of FGM were investigated. The corrosion properties of FGM and Ti600 substrate were examined. It was found that insitu synthesized TiC reinforced phase distributed in FGM evenly in the form of globular grains, which had three main different shapes, such as bulky or imperfect arborescent crystal, fine or approximately equiaxial crystal and chopped fibriform crystal. FGM and NFGM had an average hardness of approximately 1450 HV, 4.5～5 times than that of Ti600 substrates, attributing to a rapidly solidified microstructure and TiC primary dendrites. With the reducing of weight percentage of TiC, microhardness of FGM decreased gradiently and continuously. The corrosion resistance of FGM and Ti600 was good. Polarization potential was low and the corrosion current was around 108 A·cm-2 level. Otherwise, the corrosion resistance of FGM was improved. Corrosion current and resistance were 0.72 and 1.31 times than that of Ti600 substrates, respectively. |
| Key words: Timatrix functional gradient layer microstructure microhardness corrosion |
