Abstract:
Chemical etching is a process applies a strong chemical solution, called etchant to the
surface of a workpiece to gradually remove any unwanted workpiece material.
Basically, it is corrosion controlled process and is an irreversible chemical reaction. It
is widely used as a nontraditional machining process to produce a geometrically
complex and dimensional accurate component. Chemical etching is a useful process to
reduce the excess mass of a workpiece material. In this study, Aluminium (Al) was
etched in a solution of Copper(II) Sulphate (Cu(II) S04) and Sodium Chloride (NaCl)
where Cu(II) S04 act as the limiting reactant or etchant for the electrochemical
reaction to occur. The beneficial using this etchant is that there is no production of
harmful gases compared to etching with mineral acids such as nitric and hydrochloride
acid. The chemical etching of Al was carried out using single side immersion etching
method where the Al samples were purposely mounted in epoxy resin with an exposed
area of 4 cm
2
for efficient grinding and polishing. The experimental study of the
chemical etching of Al was conducted at different etching temperature and also at
different concentration of the etchant. The parameter on the selected chemical etching
effects on the depth of etch, weight loss, and also the surface finish quality of the Al
were investigated. As a result, It was observed that Cu(II) S04 has a fast etch rate and
was a useful etchant for Al. When the etching temperature and the etchant
concentration increase, the Al etches rate increase, tend to have a greater depth of etch
and weight loss which also results in a better surface quality.
