Al含量对TiAlN涂层结构及性能的影响  

Effect of Al Content on Microstructure and Properties of TiAlN Coatings

作　　者：王北川 陈利[1,2] WANG Bei-chuan;CHEN Li(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Zhuzhou Cemented Carbide Cutting Tools Co.,Ltd.,Zhuzhou 412007,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]株洲钻石切削刀具股份有限公司,湖南株洲412007

出　　处：《表面技术》2022年第2期29-38,共10页Surface Technology

基　　金：国家自然科学基金(51775560)。

摘　　要：目的系统研究Al含量对TiAlN涂层结构以及硬度、热稳定性、抗氧化性能和耐腐蚀性能的影响。方法利用阴极弧蒸发技术,采用Ti、Ti_(50)Al_(50)、Ti_(40)Al_(60)和Ti_(33)Al_(67)靶材制备出4种Ti_(1‒x)Al_(x)N涂层。分别利用能量色散X射线光谱仪(EDX)、X射线衍射仪(XRD)、扫描电镜(SEM)、纳米压痕仪、热重分析仪(TGA)和以及电化学工作站,分析了涂层的成分、微观结构、力学性能、热稳定性、抗氧化性和耐蚀性。结果4种Ti_(1‒x)Al_(x)N涂层均为面心立方结构,硬度由TiN的~26.4 GPa上升到Ti_(0.38)Al_(0.62)N的~32.7 GPa。Ti_(0.55)Al_(0.45)N和Ti_(0.44)Al_(0.56)N涂层在1100℃退火后,可检测到六方铅锌矿结构(w-)AlN相,而Ti_(0.38)Al_(0.62)N涂层在1000℃退火后便可检测到w-AlN相。Ti_(0.55)Al_(0.45)N和Ti_(0.44)Al_(0.56)N涂层的硬度在900℃退火后达到最高值,分别为~32.8 GPa和~33.3 GPa;而Ti_(0.38)Al_(0.62)N涂层的硬度在800℃时达到最高值,为~36.2 GPa。在800℃氧化20 h后,TiN已经被完全氧化,Ti_(0.55)Al_(0.45)N、Ti_(0.44)Al_(0.56)N和Ti_(0.38)Al_(0.62)N的氧化层厚度分别为~3.5、~0.6、~0.6μm。Ti_(0.55)Al_(0.45)N、Ti_(0.44)Al_(0.56)N、Ti_(0.38)Al_(0.62)N在抛物线氧化阶段的氧化激活能分别为530.9、370、375.9 kJ/mol。TiN、Ti_(0.55)Al_(0.45)N、Ti_(0.44)Al_(0.56)N、Ti_(0.38)Al_(0.62)N涂层的极化电阻分别为4.59×10^(4)、1.97×10^(3)、3.71×10^(3)、4.42×10^(4)Ω·cm^(2)。结论x<0.62时,涂层保持单相立方结构,且晶格常数和晶粒尺寸随Al含量的增加而减小。Al含量的提高优化了TiAlN涂层的力学性能,促进了涂层的热分解。Ti_(0.44)Al_(0.56)N涂层具有最优的抗氧化性能。另外,Al的加入降低了TiN涂层的抗腐蚀性能,但是含Al涂层的抗腐蚀性随Al含量的增加而增大。To investigate the effect of Al content on structure as well as mechanical properties,thermal stability,oxidation resistance and corrosion resistance of TiAlN coating completely,we deposited 4 Ti_(1‒x)Al_(x)N coatings by cathodic arc evaporation on Ti,Ti_(50)Al_(50),Ti_(40)Al_(60) and Ti_(33)Al_(67) targets.The composition,structure,mechanical properties,thermal stability,oxidation resistance and corrosion resistance of Ti_(1‒x)Al_(x)N coatings were studied in detail by energy-dispersive X-ray spectrometer(EDX),X-ray diffraction,scanning electron microscopy(SEM)with,nanoindentation,thermal gravimetric analyzer(TGA)and electrochemical workstation.All Ti_(1‒x)Al_(x)N coatings exhibit a face-centered cubic(fcc-)structure.With the increase of Al content,the hardness values of Ti_(1‒x)Al_(x)N continue to increase from~26.4 GPa of TiN to~32.7 GPa of Ti_(0.38)Al_(0.62)N.We detected the wurtzite(w-)AlN phase in Ti_(0.55)Al_(0.45)N and Ti_(0.44)Al_(0.56)N after annealing at 1100℃,however,in Ti_(0.38)Al_(0.62)N decrease to 1000℃.During the annealing process,the Ti_(0.55)Al_(0.45)N and Ti_(0.44)Al_(0.56)N show the highest hardness of~32.8 GPa and~33.3 GPa after annealing at 900℃respectively,and Ti_(0.38)Al_(0.62)N exhibits the highest hardness of~36.2 GPa at 800℃.After oxidation at 800℃for 20 h,the TiN coating has been completely oxidized,while the oxide layer thicknesses of Ti_(0.55)Al_(0.45)N,Ti_(0.44)Al_(0.56)N and Ti_(0.38)Al_(0.62)N coatings were~3.5μm,~0.6μm and~0.6μm,respectively.In addition,the oxidation activation energies of Ti_(0.55)Al_(0.45)N,Ti_(0.44)Al_(0.56)N and Ti_(0.38)Al_(0.62)N in parabolic oxidation stage are 530.9 kJ/mol,370 kJ/mol and 375.9 kJ/mol,severally.The last,the polarization resistance of TiN,Ti_(0.55)Al_(0.45)N,Ti_(0.44)Al_(0.56)N and Ti_(0.38)Al_(0.62)N is 4.59×10^(4)Ω·cm^(2),1.97×10^(3)Ω·cm^(2),3.71×103Ω·cm^(2)and 4.42×10^(4)Ω·cm^(2),respectively.In summary,within x<0.62,the coating maintains a single-phase cubic structure.With the increase of Al content

关 键 词：TIALN涂层 硬度 热稳定性 抗氧化性能 耐腐蚀性能 

分 类 号：TG174.442[金属学及工艺—金属表面处理]