The Semi-Solid Forming Process Of Al-Si Alloy Cylinder Using In Car Engine

Hypereutectic Al-Si alloy has well heat-resistant and wear-resistant which is an appropriate material to replace the automobile engine cylinder. But the casting of hypereutectic Al-Si alloy has bad comprehensive performance, its low value in use restricts the using of the aluminum alloy silicon. The topic is producing the high-silicon aluminum alloy cylinder in car engine with new production technology of semi-solid, it makes high silicon alloy improved the mechanical properties based on keeping wear-resisting, corrosion resistant and dimension stability.This paper studies the influence of electromagnetic stirring, the second heat process and the extrusion on the organization of Al-20Si-3Fe-1Mn-4Cu-1Mg, designed a mold according to technology. Validate the feasibility of the craft by computer simulations. Ultimately, the process parameters are:reheating temperature is 580℃, keeps warm for 1 hour, the temperature of the mould is 400℃, pressure head injection speed is 2m/s. The extrusion carries on the Metal hydraulic equipment.Experiment results show:After electromagnetic stirring, the alloy distribution is more uniform. After the semi-solid deformation, the organization changed greatly, the large organizations have been reduced, and formed relatively close roundness of granular phase, from the perspective of aspect, the cylinder jacket structure is complete, the size is qualified, and the surface quality is good. In the performance point of view, tensile strength achieves 230.7 MPa, The elongation ratio increased to 1.6%, it is better than 0.8% under cast forming.,and its good comprehensive performance can satisfy the cylinder liner performance requirements.