不锈钢表面原位氧化法制备氧化物涂层的微观结构及其阻氢性能研究  

MICROSTRUCTURE AND HYDROGEN PERMEATION RESISTANCE OF THE OXIDE COATING PREPARED BY INITIAL OXIDATION METHOD ON STAINLESS STEEL

作　　者：于庆河[1] 郝雷[1] 何迪[1] 李帅[1] 米菁[1] 张子楠[1] 杜淼[1] 刘晓鹏[1] 蒋利军[1] 

机构地区：[1]北京有色金属研究总院,能源材料与技术研究所,北京100088

出　　处：《太阳能学报》2016年第10期2467-2471,共5页Acta Energiae Solaris Sinica

基　　金：基金项目:真空管批量化生产工艺研究(2012AA050601)

摘　　要：316L不锈钢广泛应用于太阳能真空集热管,管内载入高温导热油,工作温度在300~400℃之间,导热油在长期工作中会因发生热分解而变质,产生游离的氢等。氢在高温下借助渗透作用穿过不锈钢中央管进入环形真空空间,导致高温真空集热管热量损失增加,因此应在集热管内表面采用原位氧化技术制备阻氢渗透涂层。当热处理温度为750℃时通过H_2-H_2O提供低氧分压气氛,低氧分压压力为10^(-21)Pa。通过XRD,SEM和XPS确定涂层的相组成和组织结构。结果表明,涂层主要由内层的氧化铬涂层和外层的锰铬尖晶石相组成。当温度为650℃时压力分别为40、60、80和100 kPa时,阻氢性能分别提高70、61、46和42倍。不锈钢表面氧化物涂层的制备可有效抑制氘在不锈钢中的扩散。316L stainless steels are widely used in vacuum solar collectors to transport high temperature heat transfer oil about 300-400 ℃. However, after serving for a long time at high temperatures, the decomposition of heat transfer oil leads to the release of hydrogen. The released hydrogen enters the annular space and causes a significant increase of heat loss. Hydrogen permeation resistant coating on vacuum solar collector was developed by initial oxidation method. The initial oxidation atmosphere was produced by the H2-H2O mixtures at 750 ℃ and the low oxygen partial pressure was about 10^-21 Pa. The phase structure and morphology of the oxide coatings were characterized using X-ray diffraction （XRD）, scanning electron microscope （SEM） and X photoelectron spectroscopy （XPS）. The results show that the oxide coating is essentially composed of the chromium oxide in inner region and the Mn1.5Cr1.5O4 spinel of outer region. The deuterium permeation of 316L stainless steel coated with Cr2O3 coating was 70, 61, 46 and 42 times lower than that of uncoated 316L stainless steel under pressure of 40, 60, 80 and 100 kPa at 650 ℃, respectively. The chromium oxide developed on the surface of 316L stainless steel has a marked inhibiting effect on the permeability of the deuterium and the mechanism has been discussed in detail.

关 键 词：原位氧化法 真空集热管 阻氢渗透 阻氢性能 

分 类 号：TQ603.1[化学工程]