AZ91及AZ91-Y合金复合干摩擦性能的对比

为了探究AZ91镁合金的复合干摩擦行为,以未淬火45钢为摩擦副,在不同载荷下(100,200,300 N),开展AZ91及Y含量为1.0%(质量分数)合金的复合干摩擦实验。采用OM,XRD,SEM等观察合金的磨损形貌并分析磨损机理。结果表明:增加法向载荷,两试样复合磨损率线性增加但摩擦因数却逐渐减小;Al 2Y硬质颗粒可细化晶粒、弱化相界面开裂倾向以提高AZ91-Y合金耐磨性。100,300 N法向载荷下,AZ91-Y合金主要磨损机制分别为磨粒磨损和剥离磨损,与基体(AZ91)一致,其磨损率分别降低了21.7%和5.9%。

Comparison on the rolling-sliding dry friction property of AZ91 and AZ91-Y alloy

The rolling-sliding dry friction properties of AZ91 and AZ91-Y(1.0%Y)(mass fraction)were studied with 45 steel as friction pair.The experiment was carried out under different normal loads(100,200,300 N),respectively.The worn surfaces of AZ91 and AZ91-Y samples were investigated by energy dispersive spectrometer(EDS),scanning electron microscopy(SEM)and X-ray diffraction(XRD)so as to analyze wear mechanism.The results indicate that the wear rates of AZ91 and AZ91-Y samples boost linearly but the friction coefficients are decreased gradually with the increase of normal loads.Al 2Y particles can refine grains,weaken the tendency of interface cracking to improve the wear resistance.Hence,the wear rates of AZ91-Y are decreased by 21.7%and 5.9%compared with AZ91 alloy when normal loads are 100,300 N,respectively.Meanwhile,the main wear mechanisms of AZ91-Y alloy are abrasive wear and delamination wear,which is the same with AZ91 alloy.