N80 钢/SiO2 基涂层/油井水泥石的界面特征研究

为了提高固井一界面的胶结强度，采用热化学反应法在N80 钢制套管钢基体上制备SiO2 基陶瓷涂层作为套管和水泥石之间的过渡层。通过X 射线衍射结构分析、扫描电子显微镜和体视显微镜形貌观察以及划痕仪涂层结合力测试，研究了N80 钢/SiO2 基涂层/油井水泥石的界面微观结构特征和结合行为。结果表明，陶瓷涂层内部和陶瓷涂层/水泥石界面分别产生了新相MgAl2O4 和Ca54MgAl2Si16O90；陶瓷涂层与钢基体结合力的临界载荷在40 N 左右，陶瓷涂层的制备起到了提高套管与水泥石结合强度的作用。

Study on the Interface Characteristics of N80 Steels and Silica MatrixCoatings and Well Cement

In order to improve the bond strength of the first interface cementing，the silica matrix ceramic coatings were preparedon N80 steel substrates as transitional coating between casing steels and well cement by thermochemical reaction method. Thecharacteristics of the interfacial microstructures and bonding behavior were investigated by the structure，morphology andbinding forces of the samples with XRD，SEM，Stereomicroscope and Scratch Tester. The results show that the interface ofceranic coating and cement created the new phase MgAl2O4 and Ca54MgAl2Si16O90，respectively. The critical adhesion betweenthe ceranic coating and the steel matrix is 40 N or so，and the preparation of the ceranic coating is helpful to improve the bondingstrength on the first interface.