Study the effect of using different quenching mediums on erosive wear behavior of high chromium white cast iron

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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Effect of molybdenum, vanadium, boron on mechanical properties of high chromium white cast iron in as-cast condition

10.1063/1.4941614 ◽

2016 ◽

Author(s):

F. Nurjaman ◽

S. Sumardi ◽

A. Shofi ◽

M. Aryati ◽

B. Suharno

Keyword(s):

Mechanical Properties ◽

Cast Iron ◽

White Cast Iron ◽

High Chromium ◽

Cast Condition

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The influence of titanium addition on wettability of high-chromium white cast iron-matrix composites

Journal of Composite Materials ◽

10.1177/0021998318804616 ◽

2018 ◽

Vol 53 (11) ◽

pp. 1567-1576 ◽

Cited By ~ 2

Author(s):

Takalani Madzivhandila ◽

Shepherd Bhero ◽

Farouk Varachia

Keyword(s):

Cast Iron ◽

White Cast Iron ◽

Mining Industry ◽

Titanium Content ◽

High Wear Resistance ◽

Matrix Composites ◽

Ferrous Alloys ◽

Titanium Addition ◽

High Chromium ◽

Wetting Properties

The mining industry exerts ever increasing demand for components with high wear resistance to the extent that plain ferrous alloys are falling short. Innovative metal-matrix composites non-ferrous metals have been widely researched and used. Casting composites based on ferrous alloys pose monumental challenges in casting. First, the density differential results in large buoyant forces on the ceramic such that unless a rigid structure is configured, the less dense ceramic floats on the metal stream. Second, the poor wetting properties between metal and ceramic will result in inferior bonding of the matrix, hence separation of solids in service. The paper attempts to improve the bonding characteristics of zirconia and alumina through wettability studies. High-chromium white cast iron was used as a substrate. The wetting behavior of molten iron on the substrates of zirconia and alumina was investigated. The study shows that alumina is poorly wetted with copper and nickel; the wetting angles were higher than 90°. Thus, the envisaged coating of alumina with copper or nickel prior to casting of ferrous melts will not significantly alter or improve wettability of alumina. Between copper and nickel, nickel has better bonding with alumina than copper. Titanium in high-chromium white cast iron was found to improve the wetting characteristics on alumina. The wetting angle decreased with increased titanium content.

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