摘要
GH4169合金因具有良好的高温强度及耐腐蚀性等,在航空航天领域应用广泛,但其也存在表面硬度低、耐磨性差的问题。固相渗硼是提高GH4169合金耐磨性能的有效手段,但常用渗硼工艺普遍采用900℃以上高温,这会破坏合金时效处理所得到的析出相结构。本实验将GH4169合金热处理时效过程与渗硼过程相统一,通过引入ZrO_(2)作为新型催渗剂获得了厚度约8.2μm的致密渗硼层。分析发现渗硼层由Cr_(5)B_(3)、Cr_(2)B、Ni_(2)B和FexNi_(23-x)B_(6)复合相组成,表面硬度高达2622.9 HV0.1,并在与氮化硅球对磨时呈现出极低的磨损率值,即8.5×10^(-6)mm^(3)/(N·m)。
GH4169 is a classical superalloy material with good high-temperature strength,fatigue strength and corrosion resistance but also suffers from low surface hardness and poor wear resistance.Boronising treatment is one of the most effective approaches for improving the surface properties of GH4169 alloys.However,due to the high boriding temperature(i.e.,above 900℃),the precipitated phase structure obtained during the aging treatment is destroyed,which affects the mechanical performance.In the present study,a GH4169 alloy was successfully boronised under ageing conditions,and a dense boride layer with a thickness of~8.2μm was obtained.The boride layer is composed of mixed Cr_(5)B_(3),Cr_(2)B,Ni_(2)B and FexNi_(23-x)B_(6)phases and has an ultrahigh hardness of 2622.9 HV_(0.1).Additionally,ultralow wear rates(8.5×10^(-6) mm^(3)/N·m)are obtained when friction occurs against Si3N4 balls.The findings of the present study will be beneficial for the practical use of boronising treatment in nickel-based superalloys.
作者
官磊
邵孟雪
胡晨阳
陈树群
GUAN Lei;SHAO Mengxue;HU Chenyang;CHEN Shuqun(Beijing Institute of Aeronautical Materials,AECC,Beijing 100095,China;College of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China)
出处
《铸造技术》
CAS
2024年第4期349-355,共7页
Foundry Technology
基金
北京市科协青年人才托举工程(BYESS2023059)。
关键词
高温合金
低温硼化
催渗剂
磨损机制
nickel-based superalloy
low temperature boronising
activator
wear mechanism
