细化变质对免热处理压铸Al-Zn-Si-Cu合金组织及性能的影响OACSTPCD

Al-Zn-Si-Cu alloy was prepared by die casting process.The effect of ceramic nano-reinforced particles(TiC/TiB2)and Al-l0Sr modifier on mechanical properties,thermal/electrical properties and microstructure of Al-Zn-Si-Cu alloy was studied.The results show that after adding 0.5％ceramic nanoparticles alone,theα-Al phase is obviously refined,showing nearly rose-like shape,the fibrous eutectic Si phase is denser,the short rod-like Al2Cu phase is finer,and the content of Zn,Si and Cu elements in the matrix is increased,and the mechanical properties are improved.The thermal conductivity/electrical properties decreased slightly,mainly due to the increase of solute elements led to a greater degree of lattice distortion,increasing the electron scattering ability while decreasing the mean free path of electrons,resulting in a decrease in the thermal conductivity and electrical conductivity of metals.After the co-action of 0.5％ceramic nanoparticles and 0.1％Al-10Sr,the eutectic Si phase is angular passivated,and the solutes content in the matrix further increases.At this time,the mechanical properties of the alloy reach the best,with the tensile strength,yield strength and elongation of 361 MPa,213 MPa and 6.8％,respectively.Thermal conductivity 118.73 W/(m-K).