摘要
Cr_2AlC属于三元层状化合物MAX相,其兼具金属和陶瓷的综合性能,如金属的导热、导电、可加工性,陶瓷的抗氧化、耐腐蚀等性能。利用直流磁控溅射技术和后续退火工艺在高速钢基体上制备了Cr_2AlC涂层,采用XRD、SEM等研究了气体流量及热处理工艺对涂层成分和物相组成的影响。结果表明:气体流量和退火温度对Cr_2AlC相的形成至关重要,气体流量比过大和退火温度过高均不利于Cr_2AlC的形成。不同气体流量下沉积态涂层主要由Cr-C化合物、非晶或者纳米晶等组成,均没有发现Cr_2AlC相;涂层经750℃退火后不同气体流量比涂层均有一定量Cr_2AlC相形成;且Cr_2AlC相形成的温度范围随CH_4/Ar气体流量比增加而变窄。含Cr_2AlC MAX相涂层的硬度为10.6-17.6GPa,弹性模量为255.3-323.4GPa。
Ternary layered carbide Cr_2 AlC is a typical MAX phase.This compound possesses a unique combination of the merits of both metals and ceramics,such as good thermal conductivity,conductive,easy machinability,good corrosion and excellent oxidation resistance.Cr_2 AlC coatings were prepared on high speed steel substrate by DC magnetron sputtering method combined with heat post-treatment in this study.The influence of gas flow rates and heat treatmenttemperature on the composition and phase in the coatings were also characterized with XRD and SEM.The results show that:the gas flow rate and heat treatment temperature play key roles on the formation of Cr_2 AlC MAX phase.The formation of Cr_2 AlC phase is suppressed by the increment of CH_4/Ar gas flow rates and the enhancement of annealing temperature.The as-deposited coatings mainly consist of Cr-C compound and amorphous,however,Cr_2 AlC phases can be acquired after being annealed at 750 ℃ for coatings with different gas flow rate.The temperature range of Cr_2 AlC phase formation can decrease with increasing CH_4/Ar flow rate ratio.The nano-hardness and elastic modulus of coatings contain Cr_2 AlC MAX phase are 10.6-17.6GPa and 255.3-323.4GPa.
出处
《中国表面工程》
EI
CAS
CSCD
北大核心
2016年第1期64-72,共9页
China Surface Engineering
基金
国家重大科技专项(2015ZX06004-001)
宁波市国际合作项目(2014D10014)
宁波市重点科技项目(2014B10032)