PENGARUH WAKTU AUSTENITISASI PADA PROSES PELARUTAN KARBIDA BAJA MANGAN AUSTENITIK
Abstract
Austenitic manganese steel is used for components which need good wear resistance and impact resistance. The application examples of austenitic manganese steel castings are in the mining industries such as rock crusher and dredge buckets, and in transportation industry, this material was used in railroad track work such as frog. However as-cast austenitic manganese steel is brittle with low toughness due to the presence of carbides. Hence, the as-cast austenitic manganese steel should be solution treated to dissolve the carbides into austenite phase, to improve its mechanical properties. Additionally, this research is enriched by using thickness parameter, to understand the influence of the dimension. The chemical composition in the casting process is in accordance with ASTM A 128 grade A. The solution treatment processes was done using a step heating procedure at temperature 575oC and 1050oC and determined heating time. Heating temperatures were determined based on Fe-Mn-C phase diagram and by the previous researches. Holding time was determined based on the literature, and heat transfer simulation result. The effects of the solution treatment were observed in the microstructure, grain size, and hardness of the specimens to obtain the optimal solution treatment that can be used. The objective of this research is to find the suitable heat treatment method in order to produce the desirable material properties and in this case, 160HB was obtained.
References
M.S. Permana, Casting Practice of Hadfield
Manganese Steel Alloy and Effect of Solution
Treatment on its Microstructure, Thesis,
Program Magister Ilmu dan Teknik Material ITB,
Bandung 1999.
B. Widyanto, Peningkatan Pembuatan Paduan
Baja Mangan Hadfield Produk Lokal Melalui
Proses Solution Treatment, Laporan Pelaksanaan
RUT VIII Oktober 2002.
W. Hume-Rothery, an Elementary Introduction
The Structures of Alloys of Iron, Pergamon Press,
London 1966.
G. Krauss, Principles of Heat Treatment of Steel,
American Society for Metals, Metals Park, Ohio
H.S. Avery, Austenitic Manganese Steel, Metals
Handbook, Vol 1, 10th ed, Properties and Selection
Iron, Steel and High-Performance Alloy, ASM
International, 1990.
B.W. Niebel dan A.B. Draper, Modern
Manufactur Process Engineering International ed,
Mc Graw-Hill Book Company, Singapore, 1989.
D.A. Porter dan K.E. Easterling, Phase
Transformation in Metals and Alloys, 2nd Edition,
hapman & Hall, London, 1992
R. Suratman, Panduan Proses Perlakuan Panas,
Diktat Lembaga Penelitian Institut Teknologi
Bandung, 1994.
D.K. Subramanyam, Austenitic Manganese Steel
Castings, ASM Handbook 9th ed, Vol 9
Metallography and Microstructures, ASM
International, Material Park, OH. 1985.
B. Widyanto, A. Sambas dan M. Permana.
Pengaruh dimensi pada hasil Solution Treatment
Baja Mangan Hadfield, seminal Nasional Ilmu dan
Teknologi Material, ITS Surabaya, 2004.
Annual Book of ASTM Standars, Volume 03.01,
Standards Relating to Metals-Mechanical Testing,
Elevated and Low-Temperature tests, 1998.