陶瓷/金属梯度热障涂层的制备及性能评价

Fabrication and characterization of ceramic/metal gradient thermal barrier coating

为了评价陶瓷/金属梯度热障涂层的性能,设计了4种涂层方案和2种基体材料(1Cr18Ni9Ti和2Cr13).利用单枪单送粉器成功地制备了线性梯度涂层.通过观察涂层的微观结构、测量涂层的抗热震性能和热残余应力来评价涂层的性能.利用扫描电镜对各种陶瓷涂层的微观结构进行了观察和分析,利用X射线能谱分析得到了陶瓷梯度涂层试样中的不同区域的衍射图.热震试验表明,梯度涂层比非梯度涂层具有更好的抗热震性能.采用钻孔法对不同涂层方案进行了残余应力的测量,结果表明,压应力出现在1Cr18Ni9Ti基体材料上,而拉应力出现在2Cr13基体材料上.

Four coating schemes and two substrate materials were designed to evaluate the characteris tics of the ceramic/metal gradient thermal barrier coating. The gradient coating was well prepared by the plasma spray with the single torch and the single feeder. The coating performance was evaluated by observing microstructure, measuring thermal shock resistance and thermal residual stress. The coating microstructure was observed by scanning electron microscope （SEM）. Diffractive peaks for the gradient coating were got at different zones by X-ray spectroscopy （XRS）. The thermal shock ex periment shows that the thermal shock resistance property of the gradient coating is better than that of the non gradient coating. The measurements of thermal residual stresses in different coating schemes were carried out by the hole-drilling method;the results show that the compressional stress appears on 1Cr18Ni9Ti substrate and the tensile stress presents on 2Cr13 substrate.