Research On Homogeneousness By Semi-solid Forging Of 6061 Aluminum Alloy

With the development of light weight of transportation field,electric products field,aerospace industry parts,the traditional manufacturing technology cannot completely satisfy the requirements for manufacturing some important aluminum alloy parts.Therefore,kinds of new advanced technology needed to meet both preparation and properties of aluminum alloy parts.Semisolid die forging technology as the 21 st century a new net shaping technology and has received the widespread attention.This method of forming,has the advantages of efficient production,die life long,the product with high performance,wide range of application,economic and environmental protection etc.6061 aluminum alloy belongs to Al-Si-Mg alloy,has the advantages of rust-resistance,easy to coating,Good machinability and workability.But 6061 aluminium alloy easy to appear Organization and the composition is not uniform phenomenon when semisolid die forging forming,Based on the 6061 aluminum alloy for example,to study thethe process parameters of 6061 aluminum alloy semisolid die forging the effects of the homogeneousness of cup of castings.With the more traditional mechanical mixing method to make semi-solid slurry,by quantitative metallographic method to analyze the water quench tissue samples,And using image analysis software to determine the primary solid fraction of water quench solid-phase sample,get the relationship between the primary solid fraction and alloy temperature,With the more traditional mechanical mixing method to make semi-solid slurry,through cup of sample mould for semi-solid forming,get the cup of castings of components under different process parameters(Temperature of the alloy,head temperature,hold time and the filling speed).In order to establish the relationship between the process parameters and microstructure segregation,We introduce the concept of the liquid phase segregation,Through the calculation of the liquid phase segregation of cup of castings section,analysis of the influence law of semisolid dieThrough the direct-reading spectrometer to analysis the elementary composition of cup of castings section,We introduce the concept of the composition segregation.Through the calculation of the composition segregation of cup of castings section,analysis of the influence law of semisolid die forging process parameters for composition segregation,and find out the reasonable process parameters.Homogenization annealing treatment was carried out on part of the cup of castings,and then analysis of the compositions and microstructures of the cup of castings after homogenization annealing treatment,homogenization annealing treatment has certain improvement effect to microstructure uniformity and composition uniformity of cup of castings.Comprehensive analysis of various process parameters:the microstructure uniformity and composition uniformity of cup of castings is more homogeneous when alloy temperature about 645?,die head temperature about 320 ?,keep time to about 2 seconds,the filling rate about 200 mm per minute.