STUDI PEMBUATAN STRUKTUR GLOBULAR DENGAN METODE SIMA UNTUK PROSES SEMISOLID FORMING
Abstract: The aim of this
research is to study the making
of globular microstructure by the SIMA (strain-induced melt
activation) method for
semisolid forming materials. Semisolid forming
is a metal
working process done
in the mixture
of liquid and solid phase. SIMA is a method used in
semisolid forming process to obtain globular structured metal
by deforming the
dendritic - structured
metal in the
room temperature and then
heat it above
the solidus temperature. In
this research, the variations used are rolling percentage of
specimen and the type of mold. Material used in this research is from car velg,
which is Al-6%Si hypoeutectic Al alloy. The globular microstructure is obtained
by heating the Al-Si specimens which is
plastically deformated oin
cold rolling. The
heating temperature is 5900C
(between TS and TL) then quenched in the
water. To measure the diameter and the roundness of the grain, the image
analyst software is used.
The result shows that the globular microstructure begins to appear when
the rolling strain reach 6%, for the casting from both metal and sand mould. The larger the plastic deformation
given to the specimen, the higher the shape factor and the finer the grain
obtained.
Penulis: Bambang Kusharjanta,
Eko Surojo, Hengky Yuliawan Putra
Kode Jurnal: jptmesindd090036
