Research On Planar Solidification Of7050Aluminum Alloy

Al-Zn-Mg-Cu high-strength aluminum alloys which are a very crucial kind of light and high-strength structural materials, have a wide application in the field of aerospace and aspect of transportations or vehicles. It is very valuable to research high-strength, high-toughness and corrosion resistance aluminum alloys as the main development direction in the future. In recent years, with the rapid development of the aerospace industry and the national defense modernization, there is a great demand for Al-Zn-Mg-Cu plates with high properties. So far, the commercial production of aluminum alloy is using Direct-Chill casting process all over the world, the use of planar solidification is lower. The work is based on the Ministry of Education’s "Priority Areas of Development Project" titled as "Research of planar solidification". The paper investigated7050aluminum alloy provided by Al-Zn-Mg-Cu high-strength aluminum alloys. The equipment of planar solidification has been designed and made. After casting, the uniformity of aluminum alloy ingot should be tested and analyzed in order to study the available option of planar solidification. We want lay the foundation of planar solidification to achieve commercial application. The main conclusions are as follows:(1) By studying the effects of shunt mode and cooling plate material on the impact of the temperature field, we concluded that the temperature field in the program of bidirectional shunt and steel cooling is consistent.(2) Content of solute elements in the ingot fluctuate around the average value. There is no exist of macro segregation and achieve the purpose of homogenization on planar solidification.(3) The microcosmic morphology of a-Al in solidification structure is equiaxed or equiaxed dendrite. There are significant differences with Direct-Chill casting process.(4) After rolling, the tensile strength is350MPa, the elongation value is12.22%, the hardness value is169.00Hv and the conductivity value is40.50Ms/mm. After aging, the tensile strength is545MPa, the elongation value is13.33%, the hardness value is117.50Hv and the conductivity value is43.40Ms/mm.