无机材料学报 ›› 2013, Vol. 28 ›› Issue (9): 1033-1039.DOI: 10.3724/SP.J.1077.2013.12730 CSTR: 32189.14.SP.J.1077.2013.12730

• 研究论文 • 上一篇    下一篇

激光铝热还原法制备Al2O3/Ti-Al基复合涂层

张晓伟, 刘洪喜, 蒋业华, 范氏红娥   

  1. (昆明理工大学 材料科学与工程学院, 昆明 650093)
  • 收稿日期:2012-12-03 修回日期:2013-01-08 出版日期:2013-09-20 网络出版日期:2013-08-14
  • 作者简介:张晓伟(1984-), 男, 博士研究生. E-mail: zhxw72@163.com
  • 基金资助:

    国家自然科学基金(51261013); 昆明理工大学分析测试基金(2010025, 2011008)

Microstructure of Al2O3/Ti-Al Composite Coatings Prepared by Laser Aluminum Thermal Reduction Processing

ZHANG Xiao-Wei, LIU Hong-Xi, JIANG Ye-Hua, PHAM THI Hong-Nga   

  1. (Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China)
  • Received:2012-12-03 Revised:2013-01-08 Published:2013-09-20 Online:2013-08-14
  • About author:ZHANG Xiao-Wei. E-mail: zhxw72@163.com
  • Supported by:

    National Natural Science Foundation of China(51261013); Analysis and Testing Foundation of KMUST(2010025, 2011008)

摘要: 利用Al和TiO2之间的放热化学反应, 采用激光原位合成技术在TC4钛合金基体材料表面制备了Al2O3/Ti-Al金属间化合物基复合涂层。对比分析了激光功率、激光束扫描速度和光斑尺寸变化对激光能量密度变化量的影响程度, 借助X射线衍射仪(XRD)、光学显微镜(OM)、能谱仪(EDS)和显微硬度计分别考察了激光束扫描速度对复合涂层表面宏观形貌、截面显微组织结构和显微硬度的影响。结果显示, 扫描速度的变化对激光能量密度变化量的影响程度最大, 光斑尺寸次之, 激光功率的变化影响最弱。随着激光束扫描速度的增大, 复合涂层表面渐趋粗糙, “鱼鳞纹”状形貌特征趋于明显, 复合涂层与基材结合区厚度减小。激光原位复合涂层主要由k-Al2O3和α-Al2O3增强相与α-Ti和α2-Ti3Al基体相组成。随着激光束扫描速度增大, 复合涂层内k-Al2O3部分转变为α-Al2O3, Al2O3增强相有由枝晶状向纤维状转变的趋势; 复合涂层截面显微硬度自基体至涂层表面过度平缓, 且涂层区显微硬度分布均匀, 明显高于基材平均显微硬度。

关键词: 激光熔覆, 原位合成, 铝热还原, Al2O3/Ti-Al基复合涂层, TC4钛合金

Abstract: With composite powders of Al and TiO2 systems as reactants, Al2O3 reinforced Ti-Al matrix intermetallic composite coatings were prepared on the TC4 alloy substrate by laser in-situ synthesis processing. The effects of laser power, laser scanning speed and laser spot size on laser energy density were analyzed, respectively. The macroscopic morphology, cross-section microstructure, and micro-hardness of Al2O3/Ti-Al composite coatings were characterized by optical microscope (OM), X-ray diffraction (XRD), energy dispersive spectroscope (EDS) and micro-hardness tester. The results show that scanning speed has the greatest impact on laser energy density firstly, then the laser spot size, and then the weakest is laser power. With the scanning speed increases, Al2O3/Ti-Al composite coatings surface become rougher, “fish-scale shape” morphology are more obvious, and the thickness of bonding-zone decreases. The reinforced phase of composite coating is composed of k-Al2O3 and α-Al2O3, while the matrix phase is composed of α-Ti and α2-Ti3Al. And with the increase of laser scanning speed, k-Al2O3 changes into α-Al2O3 partially. The morphology of Al2O3 reinforcement tends to change from dendrite shape to fiber. The micro-hardness of samples has a smooth transition tendency from the substrate to the coating surface. The micro-hardness distribution of coating cross section is uniform, and the average micro-hardness is significantly higher than that of the substrate.

Key words: laser cladding, in-situ synthesis, aluminothermic reduction, Al2O3/Ti-Al composite coating, TC4 alloy

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