Study On Microstructure?Properties And Application On A Kind Of Liquid Die Forging Aluminum Alloy

The paper is based on 6061 aluminum alloy and designs the 6061 alloy compositions fit casting,which can be used to analyze the refining effect of Al-5Ti-1B master alloy and the strengthening effect of heat treatment on the microstructure and properties of 6061 alloy using the analysis and testing methods such as optical microscope,scanning electron microscope,universal testing machine,hardness tester and electrochemical workstation and so on,and mold on liquid die forging the final,get good performance of the casting.It is found that the main phase of the as cast alloy is Mg₂Si,Al₂Cu,Si and?-AlFeSi.The grain size of 0.2%Al-5Ti-1B is the smallest.The tensile strength increases from 150.14MPa to179.53MPa,and the elongation rate increases from 5.5%to 8.9%,and the hardness increases from HB 56.2 to HB 60.9,and corrosion resistance is improved than no refining agent.The continue increasing of Al-5Ti-1B content can not refine the grain,because the TiB₂ particles aggregation in the grain boundary,so that the grain boundary coarsening,leading to performance degradation.The optimum process is 550?,4h,the second phase particles nearly dissolve in?-Al solid solution,and the aging treatment process is 180?,3h,the second phase particles are distributed in a fine,and the hardness value reach the highest,is 120.2HB,the tensile strength is335MPa,the elongation is 5.3%.The formulation of the alloy composition and heat treatment process applied to the 6061alloy liquid die forging.The liquid die forging process is that the pouring temperature is 720?,the patrix temperature is 200?,the mold unloading temperature is 350?,the specific pressure is 120MPa,the ratio of squeeze is 25mm/s,and the time of holding pressure is 35s.The tensile strength of the workpiece is 375MPa,and the elongation reaches 10%.