Abstract :
Grate cooler is the main object that serves as a clinker carrier at cooler
machine in the production process cement PT Indocement Tunggal Prakarsa Tbk.
The objective of this case study was to determine the lifetime of mechanical
properties as hardness and impack to the microstructure at the cooler mechine. The
material used in this research was high alloy steel type Fe-Cr of grate plate.
The result of the research showed that the composition test had a dominant
value Fe for 52,3%, Cr for 23,7% then it was classified into Fe-Cr Steel. The results
of the impack test with variation of two different lifetime were the two weeks was
0,141 J/ and the sixteen weeks was 0,139 J/ . The results of Vickers
hardness testing of 2 weeks had an average value of 232,57 VHN and 16 weeks was
253,51 VHN. The hardness value experiened improvement after treatment of
quenching cooling and garburizing. The microstructure test showed that the two
weeks had a roughly elongated microstructure with bright white color (gran growth)
perlit and martensit in the form of shaped grains columnar or oval elongated, while
the sixteen weeks had a microstructure with fine grains