Zhaohua JIANG
,
Xuetong SUN
,
Yanping LI
,
Fuping WANG
,
Y
,
ong LÜ
材料科学技术（英）
Ceramic coatings were prepared on Ti-6Al-4V alloy using ac micro-arc oxidation (MAO) in silicate-hypophosphate solution. Growth regularity and formation mechanism of ceramic coatings were discussed. It was found that during the first stage the growth rate of coatings toward the external surface was larger than that toward substrate and then the coating began to grow mainly towards Ti alloy. When the total coating thickness reaches a certain value, it would no longer increase. In addition, the variations of the composition and microstructure of ceramic coatings according to the depositing time were also investigated with X-ray diffraction (XRD) and scanning electron microscope (SEM). The amount of rutile TiO2 gradually increased, whereas the amounts of the anatase TiO2 and amorphous phases first increased and then decreased slightly.
关键词:
Titanium alloy
,
null
,
null
,
null
古一
,
夏长清
,
邱冠周
表面技术
doi:10.3969/j.issn.1001-3660.2010.01.003
涂层失效一般是由涂层与基底界面的显微组织演变引起的,对高温下含纳米Ni粉的陶瓷涂层与合金组织的演变进行了研究,结果表明:陶瓷涂层/合金试样在900 ℃下进行真空扩散退火后,合金基底内在靠近界面的附近依次出现了Al_2O_3的晶间氧化物和针状TiN氮化物析出层;在长时间扩散过程中,纳米镍粉逐渐聚集长大,与合金基底在界面处融为一体,形成涂层与基体的咬合,使涂层与基体的结合趋向于冶金结合,具有抑制涂层失效的作用.
关键词:
纳米镍粉
,
陶瓷涂层
,
真空退火
,
组织
