Die casting is a manufacturing
process that involves production of geometrically complex parts using molten
metal and reusable die casts. A simple and highly cost-effective process, die
casting has been one of the most important reasons for the industrial
revolution. In this manufacturing process, a die casting design is first created based on the size, shape and
function of the final produced part. After the design is created, the
non-ferrous metal perfect for the procedure will be chosen. The properties of
the metal will be taken into serious consideration as it will affect the design
and construction of the finished product.
As with all manufacturing processes,
sometimes there may be errors and defects in the aluminium die castings, which will ultimately affect the final
product. Some of the defects that could be seen in the die casting design are explained in this blog.
Bubbles
When the molten metal is poured
into the cast at high pressure, there are chances for bubbles to appear in the aluminium die castings.
This defect appears if the injection temperature of the metal is too high above
the standard levels. Another reason is the un-uniform cooling rate of the
molten metal.
Flash
If the metal is injected into
the cast with a very high pressure or if the clamp pressure of the cast is too
low, the molten metal will overflow and solidify outside the cast. In most
cases, a thin layer of metal will solidify and cover the parting line, which
will make it difficult to open the cast to release the product.
Unfilled sections
If proper care is not taken
during the die casting design process,
then there could be hindrances in the cast that will not allow proper flow of
the molten metal. In such cases there may be unfilled sections in the cast. So,
the final product will not be what is exactly required. The other reasons for
the appearance of the unfilled sections include slow injection, low temperature
of the molten metal when it is poured and insufficient shot volume. In all
these conditions, the flow of the liquid metal is reduced, and will not
completely fill all the sections of the cast.
Ejector Marks
During the aluminium die
casting process, if the ejection force of the liquid metal is very high, it
could create ejector marks. These defects happen because the force of the
molten metal pushes out a part of the mould. So, the mould will change shape,
and so will your finished product.
