Alloy steels carburizing

Pack and go carburizing creaie a diffused caiboii case. Base metals arc low -carbon steels and low -carbon alloy steels. Process temperature range is XIS-9.KO C H500 2000 F>. 

Carbides Steel, nitriding Steel, carburizing Steel, water-hardening Steel, oil-hardening Steel, air-hardening Nickel, cobalt alloy Steel, prehardened 44 Rc Beryllium, copper Steel, prehardened 28 Rc Aluminum bronze Steel, low alloy 6t carbon Kirksite (zinc alloy) Aluminum, alloy Brass... 

Iron-carbon-chromium-nickel alloy steels are used extensively in furnace applications such as heat treat containers, hearth components, drive chains, carburizing boxes, recuperators, regenerative burners, burner parts, and radiant tubes. The metal selection must consider the fact that the expansion rate of austenitic stainless steels is nearly twice that of ordinary steel. (See fig. 9.14.)... 

Bun] Bungardt, K., Preisendanz, H., Mersmann, T., Carburization of Plain Carbon and Chrome-Alloy Steels in Hydrogen-Benzene Vapour Mixtures (in German), Arch. Eisenhuettenwes., 36(10), 709-724 (1965) (Interfaee Phenomena, Kinetics, Experimental, 60)... 

Low alloy steels, wrought carburized, quenched tempered 429 212... 

Vacuum Diffused carbon 815-1090 (1500-2000) 75 p.m-1.5 mm (3-60 mils) 50-63(a) Low arbon steels, low-catbon alloy steels Excellent process control, bright parts, faster than is carburizing, high equipment costs... 

Gas Diffused carbon and nitrogen 760-870 (1400-1600) 75 im-0.75 nun (3-30 mils) 50-65(a) Low-carixm steels, low-caibtm alloy steels, stainless steels Lower temperanire than caibuii g (less disRution), sli dy harder case than carburizing, ccmtrol critical... 

M Carburized steel Nitrided low-alloy steel Unlubricaled through-hardeoed steel Glass-filled PTFE... 

In ancient India, a steel called wootz was made by placing very pure kon ore and wood or other carbonaceous material in a tightly sealed pot or cmcible heated to high temperature for a considerable time. Some of the carbon in the cmcible reduced the kon ore to metallic kon, which absorbed any excess carbon. The resulting kon—carbon alloy was an excellent grade of steel. In a similar way, pieces of low carbon wrought kon were placed in a pot along with a form of carbon and melted to make a fine steel. A variation of this method, in which bars that had been carburized by the cementation process were melted in a sealed pot to make steel of the best quaUty, became known as the cmcible process. 

DICTRA (Diffusion simulation software) (Borgenstam et al. 2000). DICTRA (coupled with Thermo-Calc) is a software for the simulation of diffusion in multi-component alloy systems (processes which can be simulated are for example the homogenization of alloys, micro-segregation during solidification, carburizing, and decarburizing, of steels, etc.). 

Decarburization occurs in steels and cast irons in hydrogen gas by the reaction of H with C in the steel. The decarburization rate is primarily dependent on the diffusion rate of C in the steel, but is also affected by the carbon content of the steel, alloying elements in the steel, such as chromium, impurities in the hydrogen, and of course time and temperature. Carburization of steels, the reverse of decarburization, is usually conducted at temperatures of about 900°C, but decarburization can occur at temperatures as low as 800°C. " ... 

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