Abstract:
The microstructural
changes in worn surfaces of 6Mn-2Cr and Mn13 steels before and
after wear were investigated by the use of back scattering
Mossbauer spectroscopy. The results show that there exist two
kinds of austenite for the austenitic manganese steels before
wear, one almost contains no C and the other contains C. The
carbon atoms mainly exist in the octahedren gap positions of
austenite. There is only one carbon atom as nearest neighbour
around an iron atom. Correspondingly two kinds of strain-induced
martensite are produced in the worn surface of 6Mn-2Cr steel
while wearing,. One is C and Me-free martensite whose internal
magnetic field value equals to 33.0 T and the other is C and
Me-containing martensite whose internal magnetic field value
equals to 30.5T. The C and Me-free martensite is produced under
a lower wear impact energy firstly and its weight fraction
reaches the saturated value rapidly. However, the C and
Me-containing martensite ois produced under a higher wear impact
energy and its weight fraction increases with increasing of the
impact energy of wear tests. There exist no strain-induced
martensite transformation in Mn13 steel while wearing.
Key words:
Austenitic manganess steel Mossbauer spectroscopy Strain-induced martensite Wear resistance
*Manuscript received on July 20, 1991; revised manuscript March 25, 1992
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