检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:常发[1,2,3] 周克崧[1,2,3] 佟鑫[2,3] 王娇[2,3] 刘敏[2,3] 康仲民
机构地区:[1]华南理工大学,广东广州510640 [2]广州有色金属研究院,广东广州510651 [3]广东省现代表面工程实验室,广东广州510651
出 处:《稀有金属材料与工程》2017年第3期577-584,共8页Rare Metal Materials and Engineering
基 金:National Key Basic Research Development Program of China("973 Program")(2012CB625100);Fundamental Research Funds of GGRIIT(1043113)
摘 要:本试验采用大气等离子喷涂(APS)在含有NiCoCrAlYTa粘结层的镍基高温合金基体表面沉积氧化钇部分稳定氧化锆(YSZ)热障涂层,然后采用Nd:YAG的脉冲激光对热障涂层表面进行选择性激光表面改性处理,最后对喷涂态和"桩钉结构"激光改性YSZ涂层的组织与性能进行分析研究。结果表明:选择性激光表面改性形成的单元体表面粗糙度明显降低,表面的孔隙基本消除,同时形成了垂直于表面的分割网状裂纹,激光改性的"桩钉结构"单元体中还包含有柱状晶和等轴晶组织。XRD分析发现,喷涂态与"桩钉结构"单元体中都包含有非平衡四方相T',然而经过激光改性后,喷涂态中的单斜相M消失,72°~76°范围中T'峰明显增大。结果还发现,"桩钉结构"激光表面改性后,喷涂态YSZ热障涂层的平均结合性能由7.3 MPa增大到13.3 MPa;"桩钉结构"YSZ涂层的隔热性能比喷涂态的隔热性能有所下降,这是由于激光表面改性导致陶瓷层组织结构改变所造成的。Yttria partially stabilized zirconia(YSZ) thermal barrier coatings(TBCs) were deposited by an air plasma spraying(APS) method on nickel-based superalloy with initially sprayed NiC o CrA lY Ta bond coat. After that, the surface of the plasma sprayed TBCs was subjected to selective laser modification using a Nd:YAG pulsed laser. The microstructure and performance of the plasma sprayed and peg-nail structured YSZ coatings by selective laser modification were investigated. The results reveal that selective laser modification helps to reduce the surface roughness considerably, eliminate surface porosities and produce a network of continuous cracks perpendicular to the surface. The microstructure of peg-nail structured units consists of columnar grains in the cross-section and equiaxed grains on the surface. XRD patterns show that both as-sprayed and the peg-nail structured coatings by selective laser modification consist of nonequilibrium tetragonal(T') phase; however, monoclinic(M) phase disappeared and intensity of T' phase slightly increases in the range of 72°~76°(2θ) after selective laser modification. It has been found that the average bonding strength YSZ coatings is enhanced from 7.3 MPa to 13.3 MPa after selective laser modification. Thermal insulation capability of the peg-nail structured YSZ coating by selective laser modification, as compared to the as-sprayed YSZ coating, is decreased due to microstructure change in the ceramic top coat.
关 键 词:YSZ 桩钉结构 激光表面改性 结合强度 隔热能力
分 类 号:TG174.4[金属学及工艺—金属表面处理]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.249