Anodizing is widely employed as a surface coating technique for
aluminium alloys [1]. The effect of the conditions of anodizing (such as
applied current density, voltage, type of electrolyte, and temperature)
[1–9] and intrinsic material factors (such as the presence, types and
distributions of second phase particles, alloying elements, and grain
orientation) [6,10–18] on the anodizing behaviour and morphology of
the anodic films formed on aluminium alloys have been widely researched.
With respect to self-ordering of pores, works on the influence
of the extent of induced or inherent stress on the anodizing behaviour of
aluminium alloys and works on the growth of porous oxide films on defined
aluminium crystals have been reported [19–22]. Other factors,
such as the state of the surfaces of aluminium substrates [23,24], grain
sizes, type of annealing pre-treatment [25], cold deformation [4] and
crystal orientations [26–28], have also been reported to have significant
influence on pore ordering and pore sizes. In contrast, Fan and coworkers
reported that the domain of pore ordering can extend across
the grain boundaries of the substrate [29]. This downplays the effects
of grain sizes and/or orientation on the formation of porous anodic layer.
However, it has since been established that anodizing can be used to
produce optical anisotropy on the surface of aluminiumunder polarized
illumination [30]. The optical anisotropywas said to be due to variations
in the inclination of pores as distinctively formed on the different
crystals of the aluminium with different orientations as observed by
Franklin and Stirland [31]. This led Kato and Ueda [32] to investigate
Anodizing is widely employed as a surface coating technique foraluminium alloys [1]. The effect of the conditions of anodizing (such asapplied current density, voltage, type of electrolyte, and temperature)[1–9] and intrinsic material factors (such as the presence, types anddistributions of second phase particles, alloying elements, and grainorientation) [6,10–18] on the anodizing behaviour and morphology ofthe anodic films formed on aluminium alloys have been widely researched.With respect to self-ordering of pores, works on the influenceof the extent of induced or inherent stress on the anodizing behaviour ofaluminium alloys and works on the growth of porous oxide films on definedaluminium crystals have been reported [19–22]. Other factors,such as the state of the surfaces of aluminium substrates [23,24], grainsizes, type of annealing pre-treatment [25], cold deformation [4] andcrystal orientations [26–28], have also been reported to have significantinfluence on pore ordering and pore sizes. In contrast, Fan and coworkersreported that the domain of pore ordering can extend acrossthe grain boundaries of the substrate [29]. This downplays the effectsof grain sizes and/or orientation on the formation of porous anodic layer.However, it has since been established that anodizing can be used toproduce optical anisotropy on the surface of aluminiumunder polarizedillumination [30]. The optical anisotropywas said to be due to variationsin the inclination of pores as distinctively formed on the differentcrystals of the aluminium with different orientations as observed byFranklin and Stirland [31]. This led Kato and Ueda [32] to investigate
การแปล กรุณารอสักครู่..
