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AbstractThe purpose of the research is
to improve the capability of casting ,welding and coloring
anodized aluminum of two different materials , such as Al-Mg 514
cast alloy aluminum and Al-Zn-Mg 7005 extrusion aluminum. Since
casting a 514 alloy thin rectangular test plate (250㎜×120㎜×4
㎜)for welding was not easy , the author adopted four methods
for casting and did many tests to solve it. Subsequently the
property of 514 alloy was promoted by using various
homogenization treatments and adding grain refiner , degassing
and altering cast conditions , controlling the flow rate of melt
alloy to reduce the phenomenon of shrinkage and hot tearing and
enhance the mechanical properties of 514 alloy . The suitable
cast conditions are recommended：(1)the temperature of melted
aluminum alloy be controlled in the range from 770℃to 810℃(2)
the temperature of mold be controlled in the range from 350℃to
370℃.The influence of adding alloy element and altering
homogenization treating temperature was observed by means of
Optical Microscope(OM), Scanning Electron Microscope(SEM), and
Multiple tensile test(MTS).With altering various homogenization
temperatures and adding alloy Al-Ti-B refiners and zirconium
alloy elements, the results showed that mechanical properties of
514 alloy could be improved effectively . For 514 alloy ,higher
homogenization temperature (450℃~490℃)was better than lower
homogenization temperature (410℃~430℃). In observing
microstructure of 514 alloy , it was interesting to find that
the higher homogenization temperature was , the lower the
eutectic phase in microstructure was , and the refiner in
microstructure region observed was.In the mean time , adding the
Al-Ti-B refiners and Zr adequately ,the tensile strength and
elongation of the specimens will be excellent .The SEM
fractograph inspections of tension failure areas were also
applied to check the fracture morphology , which indicated that
the fracture was of a typical ductile fracture .Choosing a
proper filler , either 4043, 5183, 5356 , or so on , to weld two
different materials was very important . After comparing the
results of various welded specimens , it was found that the 5356
filler worked better than the others in coloring match if
theoperating conditions were in the range from 134 to 156 amp
and from 13 to 14.5v.Finally , to make sulfuring acid anodizing
aluminum have excellent corrosion and wear resistance , it was
oxide coated in the following conditions : (1)the concentration
of sulfuric acid is 15％(165g/l) , (2) the operating
temperature is 17℃, and (3) the operating time is 50 min.
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