Abstract: Medium manganese white cast iron is an abrasion resistant material investigated and developed to suit our own national resources and production conditions.It had been successfully used to manufacture slurry pump volute, classifier blade, etc.in mining industry for its excellent cost effectiveness and availability.
In this paper, basing on the wear test results of medium Mn white cast iron of different compositions that had undergone different heat tratments, the effect of structure on abrasion resistance of this material in relation to the wear mechanisms of different classes of abrasive wear was discussed.
Low stress erosion wear tests were done in sand mixing pan and rubber wheel wear testing machine.Martensite-carbide structure of high hardness is most wear resistant.Boron addition to medium Mn white cast iron can increase the microhardness of carbide and bulk hardness still further but it lowers the strength and toughness of the material.Only suitable addition of B is be-nefial.This is related to the macro-erosion mechanism of wear.
High stress grinding wear tests were done in pin tester and three body rolling wear tester.The abrasion resistance is related to both hardness and toughness of the material.Matrix harness sometimes has decisive effect.The combined alloying with Cu Cr and Mo was used to obtain high
hardenability and high microhardness of the structural comstituents.Retained austenite lowering the matrix hardness is not desirable because of the microcutting mechanism in this class of abrasive wear.
Finally, repeated impact wear test was done by a reciprocating punch impinging on the surface of a reveolving ring specimen with quartz sand flowing between the contacting surfaces.The abrasion resistance depends very much on the tough-ness of the material.Low carbon content and rare earth modification to improve the morphology and distribution of carbide are both advantageous.The deformation wear mechanism predominates in this class of abrasive wear.
Thus we can conclude that the appropriate structure of a wear resistant material depends on the class of abrasive wear and the wear mechanisms involoved.