Sand casting and die casting processes have been used widely for complex automotive products such as knuckle, arm, etc.Usually, a part fabricated by casting has limited strength due to manufacturing defects such as th...Sand casting and die casting processes have been used widely for complex automotive products such as knuckle, arm, etc.Usually, a part fabricated by casting has limited strength due to manufacturing defects such as the dendrite structure, segregation and porosities.As an attempt to offer a solution to these problems, forging has been used as an alternative process.However, the forging process provides limited formability for complex shape products.Rheo-forging of metal offers not only superior mechanical strength but also requires significantly lower machine loads than solid forming processes.In order to produce semi-solid materials of the desired microstructure, a stirring process is applied during solidification of molten metal.The results of an A356 aluminum alloy sample, which are obtained by experiment and by simulation using DEFORM 3D, are present.展开更多
Ultra-large plate forgings are foundation of heavy machinery,but many parts of the type cannot be made by conventional technologies due to the characters of extreme manufacturing in terms of size and quality requireme...Ultra-large plate forgings are foundation of heavy machinery,but many parts of the type cannot be made by conventional technologies due to the characters of extreme manufacturing in terms of size and quality requirements.This paper introduced a systematically method called cylinder unfolding method(CUM)for producing large plate forgings,by using a serial of operations including“splitting”,“unfolding”,and“flattening”of a thick cylinder obtained from saddle forging.The technological route of CUM was presented in detail with an example of plate forging with the horizontal sizes of 6100 mm and thickness of 300 mm.The deformation features of saddle forging for fabricating transitional cylinders were analyzed,and then the subsequent handling steps including splitting,unfolding and flattening of the cylinder,as well as the auxiliary processing,were addressed.The practice proved that CUM can provide an efficient way for manufacturing ultra-large plate forgings and meet the strict requirements in geometry and mechanical performance,without highly increasing the investments of forming equipment and tooling.展开更多
基金Project(2009-0081077) supported by the National Research Foundation (NRF) by Korea Government
文摘Sand casting and die casting processes have been used widely for complex automotive products such as knuckle, arm, etc.Usually, a part fabricated by casting has limited strength due to manufacturing defects such as the dendrite structure, segregation and porosities.As an attempt to offer a solution to these problems, forging has been used as an alternative process.However, the forging process provides limited formability for complex shape products.Rheo-forging of metal offers not only superior mechanical strength but also requires significantly lower machine loads than solid forming processes.In order to produce semi-solid materials of the desired microstructure, a stirring process is applied during solidification of molten metal.The results of an A356 aluminum alloy sample, which are obtained by experiment and by simulation using DEFORM 3D, are present.
基金Project(cstc2018jcyjAX0159)supported by the Natural Science Foundation of Chongqing,ChinaProject(51575066)supported by the National Natural Science Foundation of China。
文摘Ultra-large plate forgings are foundation of heavy machinery,but many parts of the type cannot be made by conventional technologies due to the characters of extreme manufacturing in terms of size and quality requirements.This paper introduced a systematically method called cylinder unfolding method(CUM)for producing large plate forgings,by using a serial of operations including“splitting”,“unfolding”,and“flattening”of a thick cylinder obtained from saddle forging.The technological route of CUM was presented in detail with an example of plate forging with the horizontal sizes of 6100 mm and thickness of 300 mm.The deformation features of saddle forging for fabricating transitional cylinders were analyzed,and then the subsequent handling steps including splitting,unfolding and flattening of the cylinder,as well as the auxiliary processing,were addressed.The practice proved that CUM can provide an efficient way for manufacturing ultra-large plate forgings and meet the strict requirements in geometry and mechanical performance,without highly increasing the investments of forming equipment and tooling.
