Abstract Micro-mechanical properties such as nanohardness, elastic modulus, fracture toughness, etc. of composite coatings which consist of Al2O3 layer, Al layer and FeAl layer were evaluated by using nanoindentation method. The micrographs of nanoindentation were observed using a scanning electron microscopy (SEM). The effect of pores on Load-displacement response and crack propagation was investigated. The results show that there are some pores at micron scale or sub-micron scale within ceramic coatings. Elastic modulus and hardness of ceramic coating are about 226.4Gpa, 19.6Gpa, respectively. Mechanical properties of ceramic coatings are very discrete when the nanoindentatin depth is set as 250nm. The resistance of crack propagation of Al2O3 layer is large than that of FeAl layer. Radial crack emerges from the corner of residual impression of FeAl layer and propagates along straight line. Radial crack and lateral crack appear at nanoindentation of PEO coating and the cracks’ paths are deflected.
[1]Yerokhin A L,Nie X,Leyland A,Matthews A.Surf Coat Technol,1999;122:73 [2]Guan Y J,Xia Y.Trans Nonferrous Met Soc Chin,2006; 16:1097 [3]Xue W B,Deng Z W,Chen RY,Zhang T H.Thin Solid Films,2000;372:114 [4]Wu Z Q,Xia Y,Guan Y J.Trans Mater Heat Treat,2006; 27(2):103 (吴振强，夏原，关永军材料热处理学报，2006；27(2)：103) [5]Wu Z Q,Xia Y,Zhang C J,Li G.J Inorg Mater,2007; 22:534 (吴振强，夏原，张春杰，李光．无机材料学报，2007；22：534) [6]Gu W C,Shen D J,Wang Y L,Chen G L,Feng W R, Zhang G L,Fan S H,Liu C Z,Yang S Z.Appl Surf Sci, 2006;252:2977 [7]Yu S X,Xia Y,Guan Y J.Trans Nonferrous Met Soc Chin,2004:14(Suppl.2):310 [8]Fischer-Cripps A C.Nanoindentation.New York: Spring-Verlag,2002:96 [9]Oliver W C,Pharr G M.J Mater Res,1992;7:1564 [10]Page T F,Oliver W C,McHargue C J.J Mater Res,1992; 7:450 [11]Zhai C S,Yang L,Wang J,ZhaoW B,Sun B D.J Inorg Mater,2005;20:1500 (翟长生，杨力，王俊，赵文明，孙宝德．无饥材料学报，2005；20：1500) [12]Voevdin A A,Yerokhin A L,Lyubimov V V,Donley M S, Zabinski J S.Surf Coat Technol,1996;86-97:516 [13]Xue W B,Deng Z W,Chen R Y,Zhang T H.Acta Metall Sin,1999;35:638 (薛文斌，邓志喊，陈如意，张通和．金属学报，1999；35：638) [14]Xin S G.Song L X,Zhao R G,Hu X F.Surf Coat Technol, 2005;199:184 [15]Curran J A,Clyne T W.Surf Coat Technol,2006;54: 1985 [16]Anstis G R,Chantikul P,Lawn B R,Marshall D B.J Am Ceram Soc,1981;64:533 [17]Zhang T H.J Exp Mech,2004;19:437 (张泰华．实验力学，2004；19：437) [18]Palmqvist S.Jernkontorets Ann,1957;141:303 [19]Zhang S,Sun D,Fu Y Q,Du H J.Surf Coat Technol, 2005;198:74 [20]Xu Z H,Rowcliffe D.Surf Coat Technol,2002;161:44 [21]Luo H,Goberman D,Shaw L,Gell M.Mater Sci Eng, 2003;A346:237
