该研究通过大气等离子喷涂法制备了粘接层为NiCoCrAlYTa合金、陶瓷层为YSZ和La2Ce2O7 (LC)的双陶瓷层热障涂层(DCL-TBCs), 并提出了一种采用脉冲Nd:YAG激光的新型桩钉结构激光改性方法。结果表明, 激光改性后, 双陶瓷层热障涂层的表面粗糙度较喷涂前有明显提高; 在激光改性的桩钉结构单元中可以发现陶瓷层的完全再结晶, 以及致密的柱状微结构; 由于激光改性构建的桩钉结构使得整个LC层和部分YSZ层产生了再熔化与再溶解, 极大地提高了界面结合性能和结合强度, 因此激光改性后的双陶瓷层热障涂层比常规的双陶瓷层热障涂层具有更好的抗脱粘性能。

In this study an innovative peg-nail structured laser modification was carried out double-ceramic-layer thermal barrier coating (DCL-TBCs) by a pulsed Nd:YAG laser which were fabricated by a NiCoCrAlYTa bond coat and two ceramic top coat (YSZ and La2Ce2O7, LC) sprayed by air plasma spraying. Results indicate that the roughness of the laser modified surface has significantly improved, compared with as-sprayed coatings. The completely recrystallization can be found in the peg-nail structured laser modified unit, including a fully dense columnar microstructure. Due to the peg-nail structured laser modification which generated re-melting and resolidificating at the whole LC coat and partial YSZ coat, can greatly improve the interface bonding property and the bonding strength, the peg-nail structured laser modified samples have better spallation or delamination resistance than the normal as-sprayed DCL-TBCs.