摘要
采用SEM、EPMA、XRD对钢表面镍基ZrO_2(2Y)陶瓷激光熔覆层进行了分析。通过调整激光工艺参数可以在钢表面获得与基材结合良好的陶瓷熔覆层,其最高硬度值可达1700HV_(0.2)。陶瓷层主要由t-ZrO_2和少量γ-Ni构成,表层的ZrO_2呈等轴状结晶。激光熔覆的快速加热和冷却过程抑制了ZrO_2的t→m相变,以四方相的形式保留下来。过渡区的zr元素凝固后以白色颗粒状局部偏聚,而Ni元素主要分布在熔化基体晶粒内,其含量比陶瓷层高得多,出现一定程度的分层。
The microstructure of laser clad ZrO_2(2Y) plus Ni-base alloy layer on 45 steel was analysed by SRM, EPMA and XRD. An excellent metallurgical bonding between the coating and substrate is obtained by adjusting the laser parameters. The microliardness of coating is up to 1700 HV_(0.2). The la,ser clad region consists mainly of t-ZrO_2 and Y-Ni. The high heating and cooling rate caused by laser cladding restrains the t→m phase transformation. Element Zr of bonding region solidificates in the form of white particles on cooling, but element Ni mainly distributes within grain with a far more content than that in the ceramic coating.
出处
《理化检验（物理分册）》
CAS
1994年第1期11-13,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
激光熔覆
氧化锆
钢
表面
Laser cladding, ZrO_2(2Y)coating, Bonding region
