Abstract:The soluble Mg-7Al-1Zn-1Ni-1Cu alloy used for fabricating down-hole tools were prepared by cast and hot-extruded method. The microstructure, mechanical properties, corrosion behavior and application performance of the alloy were investigated. Tensile strength of the cast alloy at room temperature and 120 ℃ were 160 MPa and 150 MPa respectively. After hot-extruded treatment, the tensile strength of the soluble alloy at room temperature and 120 ℃ increased to 300 MPa and 252 MPa respectively, and the brinell hardness value also had a increase from 64 to 78. The soluble rate of hot-extruded alloy increases with temperature increasing in simulated formation water. The frac-ball fabricated by using hot-extruded alloy showed a good compressive resistance under 70 MPa at 90 ℃, which could be used in fracturing process.