Development of thermal model to analyze thermal flux distribution in thermally enhanced machining of high chrome white cast iron

ABSTRACTMinor additions (0.05-0.2 wt.%) of sodium chloride, hexachloroethane and elemental sulphur to commercial white iron melts have been found to enhance the kinetics of first stage graphitisation during subsequent annealing of white iron samples. The optimum dose of sodium chloride and hexachloroethane addition is around 0.1%. Yield strength and ductility of annealed test bars treated with NaCl or C2Cl6 compare favourably with those of untreated test bars. Sulphur treatment causes slight deterioration in mechanical properties. Fully grown nodules in both treated and untreated samples appear porous under SEM. Possible mechanisms of acceleration of graphitisation in the treated samples have been suggested.

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Spectrographic Analysis of Cast Iron Using Fused Buttons

Applied Spectroscopy ◽

10.1366/000370271779949249 ◽

1971 ◽

Vol 25 (3) ◽

pp. 342-344 ◽

Cited By ~ 2

Author(s):

John P. Cummings ◽

Ronald H. Hall ◽

Ronald J. Plenzler

Keyword(s):

Weight Loss ◽

Cast Iron ◽

High Voltage ◽

Analytical Method ◽

White Cast Iron ◽

Inert Atmosphere ◽

Spectrographic Analysis ◽

Analytical Results ◽

Good Homogeneity

This paper presents an analytical method for the determination of minor metals in white cast iron fused buttons. This method enables the measurement of metals in cast iron with rapidity and excellent analytical results. Buttons of 40 g appear to be ideal but smaller button samples can be tolerated. The fused buttons have good homogeneity, very slight weight loss, and no significant change in composition. Metal cast spectrochemical samples are analyzed in an inert atmosphere utilizing a high voltage spark.

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The Joint Effects of Nitriding and Parameters Related to the Destabilisation of Austenite on Wear Resistance in White Cast Iron with 25% Cr

Metals ◽

10.3390/met11010085 ◽

2021 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Alejandro González-Pociño ◽

Florentino Alvarez-Antolin ◽

Juan Asensio-Lozano

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

White Cast Iron ◽

Nitrided Layer ◽

Erosive Wear ◽

Air Cooling ◽

Cast Irons ◽

Eutectic Carbides ◽

Noticeable Increase ◽

Ionic Nitriding

In this article, the effects of an ionic nitriding treatment are analysed, together with deliberate variation of different thermal parameters associated with the destabilisation of austenite, on erosive wear resistance of white cast irons with 25% Cr. The methodology followed in this research was an experimental design, where six factors were analyzed by performing eight experiments. The thickness of the nitrided layer is much smaller than in white cast iron with lower percentages in Cr, never reaching 20 microns. The nitriding treatment entails considerable softening of the material underneath the nitriding layer. This softening behaviour becomes partially inhibited when the destabilisation temperature of austenite is 1100 °C and dwell times at such temperature are prolonged. This temperature seems to play a significant role in the solubilization of non-equilibrium eutectic carbides, formed during industrial solidification. The nitriding treatment leads to additional hardening, which, in these cases, favours a second destabilisation of austenite, with additional precipitation of secondary carbides and the transformation of retained austenite into martensite. Despite softening of the material, the nitriding treatment, together with air-cooling after destabilisation of the austenite, allows a noticeable increase in resistance to erosive wear.

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