In order to solve the processing difficulty of a new vermicular graphite cast iron RuT400 used in engines

the addition experiment of micro boron nitride(BN) on vermicular graphite cast iron was carried out

and the microstructure and mechanical properties of graphite cast iron were analyzed by means of metallographic test

tensile test

hardness test and friction test. Experimental results show that BN has no influence on the morphology and content of graphite

pearlite and ferrite

and has little effect on the tensile 〖JP2〗strength and hardness

but has a great influence on the friction properties. When the content of BN is 0.0144%

the wearing resistance is the best. BN can effectively reduce the surface roughness of vermicular graphite cast iron in turning

and it would make the process more stable. Therefore

it is feasible to improve the process ability by adding micro BN to produce self lubrication function without affecting the mechanical properties of vermicular graphite cast iron.