ANALISIS PENGARUH PROSES VARIASI TEMPERATUR PACK CARBURIZING ARANG SEKAM PADI TERHADAP KEKERASAN, STRUKTUR MIKRO & KOMPOSISI KIMIA BAJA ASTM A36

Abstract

Abstrak
Pada proses perlakuan panas, terdapat beberapa metode perlakuan panas pada baja karbon yaitu pack
carburizing, carbonitriding, cyaniding, dan nitriding. pack carburizing merupakan proses perlakuan panas
(heat treatment) yang dilakukan dengan cara mendifusikan unsur karbon pada permukaan logam yang
kemudian dipanaskan pada suhu austenitnya. Tujuan pack carburizing yaitu untuk menaikkan kadar karbon
pada lapisan permukaan baja sehingga didapatkan material baja yang memiliki permukaan keras dan sifat
mekanik lain-nya. Dalam penelitian ini metode yang digunakan adalah metode penelitian kuantitatif
eksperimental, yaitu metode uji coba dan analisis terhadap nilai kekerasan dan struktur mikro pada proses
pack carburizing dengan variasi temperatur yang berbeda. Pada pengujian komposisi kimia terhadap sampel
baja karbon rendah ASTM A36 sebelum dan sesudah proses pack carburizing terjadi kenaikan kadar karbon
sebesar 94,4%. 2. Pada pengujian kekerasan Rockwell setelah proses pack carburizing 870°C dengan arang
sekam padi 90% dan BaCO3 10% didapat nilai kekerasan rata-rata sebesar 22,41 HRC dan case depth
179.64 µm. 3. Pada pengujian kekerasan Rockwell t setelah proses pack carburizing 910°C dengan arang
sekam padi 90% dan BaCO3 10% didapat nilai kekerasan rata-rata sebesar 41,93 HRC dan case depth
186,54 µm. 4. Berdasarkan perbandingan variasi temperatur 870°C dan 910°C terhadap nilai persentase
kenaikan karbon terjadi kenaikan sebesar 87,10%. 5. Berdasarkan struktur mikro pada temperatur 870°C
didapatkan struktur fasa 6. Berdasarkan struktur mikro pada temperatur 910°C didapatkan struktur fasa.
Kata kunci: carburizing, struktur mikro, kekerasan, rockwell
Abstract
In the heat treatment process, there are several heat treatment methods for carbon steel, namely pack
carburizing, carbonitriding, cyaniding, and nitriding. pack carburizing is a heat treatment process that is
carried out by diffusing carbon elements on a metal surface which is then heated to its austenite
temperature. The purpose of pack carburizing is to increase the carbon content in the steel surface layer
so that a steel material that has a hard surface and other mechanical properties is obtained. In this study
the method used was quantitative experimental research method, namely the method of testing and
analysis of hardness values and microstructures in the pack carburizing process with different
temperature variations. In testing the chemical composition of ASTM A36 low carbon steel samples before
and after the pack carburizing process, there was an increase in carbon content of 94.4%. 2. In the
Rockwell hardness test after the pack carburizing process at 870°C with 90% rice husk charcoal and 10%
BaCO3, the average hardness value was 22.41 HRC and a case depth of 179.64 µm. 3. In the Rockwell t
hardness test after the pack carburizing process at 910°C with 90% rice husk charcoal and 10% BaCO3,
the average hardness value was 41.93 HRC and a case depth of 186.54 µm. 4. Based on a comparison of
temperature variations of 870°C and 910°C to the percentage increase in carbon, there was an increase of
87.10%. 5. Based on the microstructure at 870°C, the phase structure is obtained. 6. Based on the
microstructure, at 910°C, the phase structure is obtained.
Keywords: carburizing, microstructure, hardness, rockwell