CAJ | 학술논문

为了缓解涂层和基体之间的热失配应力，采用化学镀方法在2A70铝合金表面上制备Ni-P和Ni-Cu-P过渡层；然后在镀层表面依次制备CoNiCrAlY粘结层和ZrO2-8%Y2O3(8YSZ)陶瓷层(质量分数)，获得复合热障涂层；并采用热循环方法评定该涂层体系的抗热震性能。结果表明，采用Ni-P镀层和Ni-Cu-P镀层作为过渡层的试样的热震寿命分别约为1000次和500次；Ni和Al元素的互扩散使过渡层与基体界面区域形成了扩散层和岛状颗粒，一些颗粒与扩散层连通后提高了涂层与基体的结合强度，但孤立的颗粒由于变形能力差，对涂层的寿命有不利影响；在交变应力下颗粒与基体界面处会形成裂纹，并最终导致涂层剥离。
위료완해도층화기체지간적열실배응력，채용화학도방법재2A70려합금표면상제비Ni-P화Ni-Cu-P과도층；연후재도층표면의차제비CoNiCrAlY점결층화ZrO2-8%Y2O3(8YSZ)도자층(질량분수)，획득복합열장도층；병채용열순배방법평정해도층체계적항열진성능。결과표명，채용Ni-P도층화Ni-Cu-P도층작위과도층적시양적열진수명분별약위1000차화500차；Ni화Al원소적호확산사과도층여기체계면구역형성료확산층화도상과립，일사과립여확산층련통후제고료도층여기체적결합강도，단고립적과립유우변형능력차，대도층적수명유불리영향；재교변응력하과립여기체계면처회형성렬문，병최종도치도층박리。
To relieve the thermal mismatch stress between coatings and substrate, Ni-P and Ni-Cu-P electroless platings were fabricated onto 2A70 aluminum as interlayers. Subsequently, the specimen with plating was covered by CoNiCrAlY bond coat and ZrO2-8%Y2O3(8YSZ) top coat (mass fraction), then a novel thermal barrier coating (TBC) was produced. The thermal shock resistance of TBCs was evaluated by heat cycle test. The results indicate that the lifetimes of TBC with Ni-P interlayer and Ni-Cu-P interlayer are about 1000 cycles and 500 cycles, respectively. The interdiffusion of Ni and Al results in the formation of diffusion layers and island particles at the interface between interlayers and substrate. The connection between particles and diffusion layers improves the adhesion of coatings with substrate, while isolate particles are harmful to the lifetime of coatings due to their poor deformation ability under alternative stress. Crack initiation happens at the interfaces between particles and substrate, which leads to coatings spallation.