Microstructures and wear properties of brass synchroniser rings

In this study, the wear behaviour of synchroniser rings produced from a (α+β) high-strength brass was investigated under dry sliding conditions by pin on disc and reciprocating wear tests. Pin on disc tests were conducted on M2 quality high speed tool steel and 120-mesh Al2O3 abrasive papers. AISI 52100 quality steel balls were used in reciprocating tests as counterface. A correlation between microstructure, hardness and wear resistance was established for the investigated synchroniser rings. An increase of α-phase from 8 to 23 vol.% decreased the hardness from 281 to 250 HV and increased the wear resistance. Depending on the type of wear test and counterface, the increment in wear resistance is found in between 15 and 80%.