| This paper took ZL102 aluminum alloy materials as the research object . The sample is divided into two parts, one for the cast state of the sample, and the second for the annealing state of the sample. Two samples were carried out on the hot extrusion test, and compare the test results, obtained the best technical parameters.ZL102 cast aluminum alloy by 495±5℃annealing, the microstructure of needle-like silicon phase in the annealing process took place and gathered the ball, and the interface can be reduced to a more stable state of thermodynamics. Its strength and hardness are lower than the cast, and the elongation increased 2 times, the section shrinkage increased 3 times, its extensibility was heightened greatly, the forming property got great improvement ultimately.In the course of extrusion, ZL102 aluminum alloy do not occur the cracks and fixed Phenomenon, and less squeeze pressure. Annealing squeezed state have lower actual average squeeze pressure than not annealing . ZL102 aluminum alloy by the following extrusion, their mechanical properties at room temperature has been varying degrees of improvement. According to the measured experimental data analysis:Influence of extrusion process parameters on mechanical properties of ZL102 aluminum alloy mainly by controlling the organization shape, size and distribution of silicon achieved. Extrusion improve the microsructure of the alloy effectively, making silicon particles (enhanced) evenly dispersed in theα-Al matrix and And accompanied by the formation of subgrain.Cast aluminum alloy for example: In the different extrusion ratios, with the extrusion temperature rising of ZL102 aluminum alloy, silicon particles gradually become larger and subgrain up, the strength become smaller, but the plastic and toughness increased. In the different extrusion temperatures, with the extrusion ratio rising silicon particles gradually become larger, the strength become smaller, the plastic and toughness raised. When extrusion temperature is 300℃and extrusion ratio is no more than than 45, the alloy could get the superior intensity,σb =159MPa; Extrusion temperature is 420℃and extrusion ratio is 60, which is the best technology that the alloy could get the superior plastic,δ=23%,ψ=34%; The best extrusion temperature of obtaining higher toughness of ZL102 cast aluminum alloy is less than380℃, influence of extrusion ratio on toughness wasn,t obvious,αk= 1. 2J·cm-2.Annealing state of aluminum alloy: In the different extrusion ratios, with the extrusion temperature rising of ZL102 aluminum alloy, silicon particles first become smaller then become larger, Subgrain grown from a small, the intensity become lower after the first increase, plastic did not change significantly,the toughness gradually increased. In the different extrusion temperatures, with the extrusion ratio rising the silicon particles gradually become larger, the intensity and toughness decreased, the plastic raised. When extrusion temperature is 460℃and extrusion ratios is more than 15, the alloy could get the superior intensity,σb =164MPa; Temperature less than 460℃and extrusion ratio more than 75, the alloy could get the superior plastic,δ=25%,ψ=38%; Extrusion temperature is 420℃and extrusion ratios more than 15, which is the best technology that the alloy could get the superior toughness,αk= 1. 7J·cm-2.In a word, this experiment comprehensive analysis about influence of extrusion process parameters on mechanical properties of ZL102 aluminum alloy, the results show that the alloy after heat treatment and hot extrusion deformation process at the above-mentioned conditions can effectively improve the mechanical properties of alloys at room temperature,which supply a scientific basis for the improvement of the extrusion parameters and the improvement of product property on the microstructure and mechanical properties, as well as open up a new pass for the deformation of cast aluminum alloy .
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