modul 2.proses pembuatan baja
DESCRIPTION
ilmu bahanTRANSCRIPT
PROSES PEMBUATAN BAJA
Modul 2 &3 Steels Making IPBMPRODI MESIN
Steels Making 122PROSES PEMBUATAN BAJA
D.R.ISpong IronHow is Steel made-I
4
MODEL BLAST FURNACE Udara Panas
BIJI BESI ( IRON ORE)Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, deep purple, to rusty red.
The iron itself is usually found in the form of magnetite (Fe3O4), hematite (Fe2O3), goethite (FeO(OH)), limonite (FeO(OH).n(H2O)) or siderite (FeCO3). Hematite is also known as "natural ore", a name which refers to the early years of mining, when certain hematite ores containing up to 66% iron could be fed directly into iron-making blast furnaces. Iron ore is the raw material used to make pig iron, which is one of the main raw materials to make steel. 98% of the mined iron ore is used to make steel.[1]Nama Meneral ( Iron Ore)
Lanjutan
BENTUK IRON ORE
PELETBRIQUETTESSINTERNODULESProses Reduksi Blast furnace
3Fe2O3+CO 2Fe3O4+ CO2Fe2O3+CO 2FeO + CO2
Lame stone : Batu Kapur ( Kalsium Karbonat CaCo3) untuk menghasilkan terak (slag)CaCo3====>CaO+CO2(terak)FeS+CaO+C=====>Fe+CaS+CO(terak)
Zone of Fusion: It is the zone where carbon ( C ) reacts with ferric oxide (FeO ) to give Iron ( Fe ) at 1300cFeO + 3C Fe + 3Co CO2+ C 2CO
LOGAM CAIR /PIG IRONBlast- furnace
STEEL MAKING PROSES O.H.F/B.O.F
LADLE-FURNACECONTINOUS CASTINGLOGAM CAIRTERPEDO-CAR
Desulfurisasi , Kandungan Sulfur diturunkan(S,P,Si)CaC2,CaO,Mg,Na2OProses pemurnian I (C,P,S,Si) dengan CO2 atau O2RH VACUM DEGASSINGPemurnian II:
Strong StirMenurunkan InclusionsMenurunkan CBASIC-OXYGEN FURNACE(B.O.F)
Open Hearth ProcessPerubahan % Unsur B.O.F
Proses Iron ore Besi Sponge
Iron-OreProses Iron ore- Sponge
Electrical Furnace- Pemaduan unsur logam
Continous casting
Menurunkan biayaMemperbaiki kualitasMeningkatkan sifat mekaniknya
Hasil-Continous castingBloomSlabBilletREHEATING HOT ROLLINGCOLD ROLLINGPICKLING PROSES1370 o C1315oCH2SO4HCL40 s.d 70 %
Hot Rolling [ 1200oC]
IIIIIITujuan Cold RollingMemperbaiki kualitas permukaan;Memperbaiki ukuran/bentuk ;Hasil Cold rollingLogam menjadi keras [mampu bentuknya rendah]Cara memperbaiki ;1. Dengan melakukan Annealing [705oC]2. Pendinginan lambat sampai [90oC]Proses Pengerolan
Cold Rolling dilakukan pada suhu di bawah Temperatur rekristalisasi
OperatorRol Bagian Atas Pelat Hasil PengerolanAnnealing after cold rollingBox annealingContinuous annealing
Logam menjadi lunakTerjadi RekristalisasiButir Memanjang Butir equaxialTEMPER ROLLING MENURUNKAN PENGARUH DARI STRAIN AGINGMEMBENTUK : UPPER & LOWER YIELDING
Struktur MikroNama Meneral Komposisi KimiaPenamaan
Oxide: Magnetite Hematite Ilmenite Limonite
Fe3O4Fe2O3FeTiO3HFeO2*Fe2O(OH)**
Ferrous-Ferric oxideFerric-OxideIron-titanium oxide}Hydrous iron oxide}
Carbonate Siderite
FeCO3Iron carbonate
Silicate Chamosite Stilpnomelane Greenalite Minnesotaite GruneriteIron Silicates
Sulphide Pyrite(iron pyrites) Marcasite(white iron pyrites) Pyrrhotite(Magnetic iron pyrite)FeS2FeS2
FeS
Iron Sulfide
Ferrous Alloy
Plant Karbon Steel
Steel
Low Alloy Steel 8% Alloying Element
Low Carbon Steel(0.5%C)
Corrosion Resistant
Heat Resistant
Wear Resistan
Ferritic
Ferritic-Pearlitic
Pearlitic
Martensitic
Bainitic
Austenitic
Precipation-Hardened
Austenitic-Ferritic
Duplex Structure