CAJ | 학술논문

基于激光熔覆技术在 TC4合金表面制备NiCoCrAlY 熔覆涂层,考察纳米稀土 La2 O3含量对熔覆涂层质量的影响。利用金相显微镜、扫描电镜以及显微硬度计对添加稀土 La2 O3含量分别为0,1％,2％和3％的涂层的微观形貌、组织及硬度进行观察和研究。结果表明,随着纳米稀土 La2 O3含量的增加,熔覆层的稀释率逐渐降低,抑制了熔覆层中柱状晶的生长,加速了枝状晶的形成,且枝状晶的分支加剧,二次枝状晶的间距减小,使熔覆层的晶粒得到细化,并且出现花朵状。添加纳米稀土 La2 O3的熔覆层硬度相对未添加的都较高,但随着其含量的增加呈现逐渐下降趋势。
기우격광용복기술재 TC4합금표면제비NiCoCrAlY 용복도층,고찰납미희토 La2 O3함량대용복도층질량적영향。이용금상현미경、소묘전경이급현미경도계대첨가희토 La2 O3함량분별위0,1％,2％화3％적도층적미관형모、조직급경도진행관찰화연구。결과표명,수착납미희토 La2 O3함량적증가,용복층적희석솔축점강저,억제료용복층중주상정적생장,가속료지상정적형성,차지상정적분지가극,이차지상정적간거감소,사용복층적정립득도세화,병차출현화타상。첨가납미희토 La2 O3적용복층경도상대미첨가적도교고,단수착기함량적증가정현축점하강추세。
NiCoCrAlY laser cladding coatings were prepared on TC4 alloy by laser cladding technology.Influence of different contents of nano-La2 O 3 particles on quality of coatings was investigated.Morphology,microstruc-ture and micro-hardness of the laser cladding coatings with 0,1%,2% and 3% nano-La2 O 3 were investigated by means of metallographic microscope,SEM and micro-hardness tester.The result indicated that with the con-tent of nano-La2 O 3 increasing,dilution rate of cladding layers decreased gradually.The growth of dendritic crystal was inhibited,and the formation of dendritic crystal accelerated.Branch of dendritic crystal was aggrava-ted and the space of with secondary dendritic crystal was decreased,which caused that the grain was refined, and the flower-like grain appeared in the cladding coating.The micro-hardness of cladding layers with nano-La2 O 3 was higher than without nano-La2 O 3 ,and the micro-hardness of cladding layers decreased gradually with the increase of content of nano-La2 O 3 .