The effect of manganese on the strain-induced martensitic transformation and high temperature wear resistance of Fe-20Cr-1C-1Si hardfacing alloy

Sliding wear tests of Fe-20Cr-1C-1Si-xMn alloys with x varying from 0 to 25 wt% were performed in air at temperatures of 25-450 degreesC under a conta ct stress of 103 MPa. During wear at 25 degreesC, low-Mn alloys containing less than 5 wt% Mn and high-Mn alloys containing more than 10 wt% Mn exhibi ted the gamma --> alpha ' and gamma --> epsilon strain-induced martensitic transformations, respectively. As the test temperature increased, low-Mn al loys showed a wear transition from mild oxidative wear to galling at a temp erature between 350 degreesC and 400 degreesC due to the absence of gamma - -> alpha ' strain-induced martensitic transformation. In the case of high-M n alloys, the mild oxidative wear was maintained until 450 degreesC, which was the highest test temperature in this study, with the formation of strai n-induced E martensite. It was considered that the gamma --> epsilon strain -induced martensitic transformation could be more beneficial to the high te mperature wear resistance of iron-base hardfacing alloy than the gamma --> alpha ' strain-induced martensitic transformation due to the higher M-d tem perature. (C) 2001 Published by Elsevier Science B.V.