The effects of the solution and aging heat treatment on the microstructure

hardness and tensile properties of ZL101 alloy with adding B and Sb were investigated.The results show that after adding B and Sb

the eutectic silicon becomes small accicular structure from coarse plate

and the long strip primaryα-Al becomes equiaxed structure.At the same heat treatment process

the eutectic silicon in B and Sb modified alloys is spheroidizing fully with the more uniform size distribution

and the precipitated aging phase in the matrix is more dispersed.In addition

the microhardness of the alloy is increased from102.4 HV to 114.6 HV compared with that without modification ones.When the heat treatment process is 540 ℃×6 hsolution+190 ℃×5 haging

the tensile strength and elongation of the B and Sb modified alloy reach 332.8 MPa and 11.73%

respectively

increased by 21.6% and 90.7%

compared with those of the unmodified alloys

and a large number of uniform and fine equiaxed dimple structures appears in the fracture.