Aluminum alloy multi-step samples were prepared in common sand mold and in chromite sand mold

and the tensile strength

yield strength

elongation and hardness of the prepared samples were examined.Meanwhile

the microstructure of the samples prepared was observed

and the grains size and DAS（secondary dendrite arm space） were comparatively analyzed.The results show that the sample prepared in chromite sand mold is obviously improved in tensile strength and is increased in elongation at the thin-walled location

meanwhile

it is superior to those in common sand mol in grains size and DAS

however

it is lower than that in common sand mold in cooling rate sensitivity.The chromite sand is more suitable for preparing the parts with high strength

however

it is not suitable for the mold materials for the complicated castings due to its intense cooling rate resulting in the low fluidity of liquid metal.So it was limited in application scope.