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ÇELİK MİKROYAPILARIÇELİK MİKROYAPILARI

Microstructure of a very-low-carbon interstitial-free steel

Cementite (arrows) at ferrite grain boundaries 0.04% C steel. 500×

Microstructure of plain carbon UNS G10150 steel showing equiaxed ferrite grains with pearlite islands

Microstructure of a slow-cooled UNS G10080 steel showing pearlite islands in a ferritic matrix

Microstructure of an as-rolled microalloyed steel plate showing equiaxed ferrite grains withbands.

Microstructure of plain carbon UNS G10400 steel showing equiaxed proeutectoid ferrite grainsoutlining the prior-austenite grain boundaries. The matrix is pearlite

Microstructure of plain carbon UNS G10800 steel showing colonies of pearlite. 4% picral etch.Original magnification 200×

Microstructure of pearlite colonies in plain carbon UNS G10800 steel taken in the scanning electron microscope. 4% picral etch. Original magnification 2000×

Microstructure of pearlite colonies in plain carbon UNS G10800 steel taken in the scanningelectron microscope. The plates of cementite are clearly revealed. 4% picral etch. Original magnification10,000×

Microstructure of plain carbon UNS G10200 steel showing acicular ferrite with some pearlite(dark etching constituent). This type of acicular appearance is called Widmanstätten structure. 500×

Microstructure of 1.2% C-Fe alloy showing cementite outlining the prior-austenite grainboundaries and cementite needles in the grains of pearlite. The grain-boundary cementite is calledproeutectoid cementite. This microstructure represents a hypereutectoid steel. 4% picral etch. Originalmagnification 200×

(a) YMK demiri birim hücresinde karbon atomu, küpün kenarındaki geniş arayer boşluğuna yerleşmiştir. (b) HMK demiri birim hücresinde küpün kenar atomları arasında daha küçük arayer boşlukları bulunur. (c) HMT birim hücre HMK birim

hücrenin karbon atomu tarafından bozulmasıyla meydana gelmektedir.

Microstructure of water-quenched low-alloy steel showing lath martensite. 2% nital etch. Original magnification 500×

Microstructure of water-quenched UNS G10800 steel showing plate martensite. The light regions between the martensite plates are retained austenite. 1000×

1.7 karbonlu ötektoidüstü çelikte iğnesel martenzit (a) Martenzit açık, artık östenit koyu. (b) martenzit koyu, artık östenit açık

Fe-0.2C alloy in the (a) water-quenched condition, followed by tempering at 690 °C

Fe-1.2C alloy in the (a) water-quenched condition, followed by tempering at 690° C (1275 °F) for(b) 1.5 × 103 s, (c) 1.03 × 104 s, and (d) 6.05 × 105 s

Microstructure of a dual-phase sheet steel with islands of martensite in a matrix of ferrite. 4%picral etch. 500×

Microstructure of heat treated low-alloy steel showing bainite. 4% picral + 2% nital etch. Original magnification 500×

Microstructure of quenched low-alloy steel showing a bainitic structure (granular bainite). 4% picral + 2% nital. Original magnification 1000×

Microstructure of quenched and tempered low-alloy UNS G43400 steel showing a mixture of bainite (dark etching constituent) and martensite (lighter gray). 4% picral + 2% nital etch. Original magnification 500×

Effect of carburizing time on case in 0.15% C steel (0.17C-0.5Si-0.64Mn, wt%) after slow cooling from pack carburization at 940 °C (1725 °F) for (a) 1 h, (b) 2 h, and (c) 4 h., 500×.

Grain structure of austenitic type 316L, solution annealed at 954 °C (1750 °F) and etched with (a)waterless Kalling's and (b) Beraha's tint etch

AISI H13, heated to 1025 °C (1875 °F), air quenched, and double tempered at 595 °C (1100 °F). 42 HRC. All martensite plus a small amount of very fine undissolved carbide. 2% nital. 1000×

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Hypoeutectic as-cast gray iron (Fe-2.8%C-1.85%Si-0.5%Mn-0.04%P-0.025%S). Flake graphitetype A. As-polished. 100×

Hypereutectic as-cast gray iron (Fe-3.3%C-2.75%Si-0.88%Mn-0.42%P-0.086%S). Flakegraphite type B. As-polished. 90× (microscopic examination 100×)

Hypereutectic as-cast gray iron (Fe-4.3%C-1.5%Si-0.5%Mn-0.12%P-0.08%S). Flake graphitetype C (kish graphite). As-polished. 100×

Hypereutectic as-cast gray iron (Fe-3.4%C-3.4%Si-0.07%Mn-0.04%P-0.03%Cr-0.47%Cu).Pointlike flake graphite type D. As-polished. 100×

Hypereutectic as-cast gray iron (Fe-2.18%C-2.49%Si-0.7%Mn-0.06%P-0.05%S). Flake graphitetype E. As-polished. 100×.

As-cast ductile iron. Nodular graphite size is 100 μm. As-polished. 100×

Ductile iron. Ferritic matrix. The casting was annealed at 900 °C (1650 °F), held 2 h, quickfurnace cooled to 730 °C (1345 °F), slow furnace cooled to 600 °C (1110 °F), and air cooled. Etched with4% nital. 100×

As-cast ductile iron. Ferritic-pearlitic matrix. Etched with 4% nital. 100×

Nodular graphite in as-cast ductile iron examined with SEM. Sample was deeply etched with 50% HCl. 1000×

As-cast iron with compacted graphite (Fe-3.7%C-2.3%Si-0.21%Mn-0.03%P-0.01%S-0.82%Ni-0.02%Mg). Graphite size is 80 to 160 μm. As polished. 100×

As-cast iron with compacted graphite (Fe-2.8%C-1.9%Si-0.55%Mn-0.04%P-0.2%S-0.018%Mg).Ferritic-pearlitic matrix. Etched with 4% nital. 100×

Malleable iron (Fe-2.95%C-1.2%Si-0.53%Mn-0.06%P-0.21%S-0.08%Cr-0.10%Cu-0.07%Ni-<0.01%Al). The casting was annealed: at 950 °C (1740 °F), held 10 h, furnace cooled to 720 °C (1330 °F),held 16 h, and air cooled. Pearlitic-ferritic matrix. Etched with 4% nital. 125× (microscopicmagnification 100×)

As-cast white iron (Fe-3.0%C-2.7%Si-0.45%Mn-0.07%P-0.025%S). C, cementite; P, pearlite.Etched with 4% nital. 400×

White high-chromium cast iron (see Fig. 43). PC, primary carbides; EC, eutectic carbides inmartensitic matrix with fine, globular secondary carbides. The casting was heat treated at 1000 °C (1830°F), held 1 h, furnace cooled to 550 °C (1020 °F), held 4 h in a 400 °C (750 °F) salt bath, and air cooled.Etched with glyceregia. 1000×

As-cast gray iron (Fe-3.33%C-1.64%Si-0.31%Mn-1.37%P-0.107%S). Ternary phosphoruseutectic. Etched with 4% nital. 1300× (microscopic magnification 1000×)