The continuous extrusion forming process for producing large section copper concave bus bar under different extrusion wheel angular velocities was studied by three-dimensional finite element technology based on softwa...The continuous extrusion forming process for producing large section copper concave bus bar under different extrusion wheel angular velocities was studied by three-dimensional finite element technology based on software DEFORM-3D. The rigid-viscoplastic constitutive equation was employed in the model. The numerical simulation results show that the deformation body flow velocity in the die orifice increases gradually with the increase of the extrusion wheel angular velocity. But slippage between the rod and extrusion wheel occurs when the extrusion wheel angular velocity is high. The effective stress near the die orifice enhances gradually with increasing extrusion wheel angular velocity. High stress is concentrated in adjacent regions of the flash gap. The effective strain gradient is greater near the abutment than that near the die orifice. The effective strain of the product increases gradually with increasing extrusion wheel angular velocity. In the deformation process, the deformation body temperature increases remarkably due to friction and deformation. So the cooling is necessary in the region of the die and tools.展开更多
Steel has been used as a traditional wheel materials for a long time.Before 1980' s,over 90% wheels were made of steels.Then,the yield strength of wheel steels increased gradually from 240 -350 MPa to 600 MPa or h...Steel has been used as a traditional wheel materials for a long time.Before 1980' s,over 90% wheels were made of steels.Then,the yield strength of wheel steels increased gradually from 240 -350 MPa to 600 MPa or higher.The advanced high strength steels become the main wheel materials.Since 1990's,DP600 has been broadly applied in steel wheels oversea.However,there was little research of application of high strength steel wheels(especially wheel disc) in domestic wheel industrial.In presence, DP600 steel wheel is only developed in FAWSH by using imported CKD.Other domestic steel wheel manufacturers did little work on high strength DP600 wheel discs.Baosteel wheels Co.Ltd.is the first domestic company producing DP600 steel discs and has become the leading company in production of high strength wheel.Because of the high strength of DP600,its formability,springback,and wrinkle have become the keys of the successful application of DP600 steel.In this paper,the metallurgical and mechanical properties are firstly introduced and formation problems of DP600 are described compared to traditional steels.Secondly,FLD analysis has been done.Wrinkle and more springback are recognized.To solve these problems,an optimized solution is designed and the good result is obtained.The test has shown that the fatigue property of steel wheel discs made by DP600 have been greatly improved.展开更多
文摘The continuous extrusion forming process for producing large section copper concave bus bar under different extrusion wheel angular velocities was studied by three-dimensional finite element technology based on software DEFORM-3D. The rigid-viscoplastic constitutive equation was employed in the model. The numerical simulation results show that the deformation body flow velocity in the die orifice increases gradually with the increase of the extrusion wheel angular velocity. But slippage between the rod and extrusion wheel occurs when the extrusion wheel angular velocity is high. The effective stress near the die orifice enhances gradually with increasing extrusion wheel angular velocity. High stress is concentrated in adjacent regions of the flash gap. The effective strain gradient is greater near the abutment than that near the die orifice. The effective strain of the product increases gradually with increasing extrusion wheel angular velocity. In the deformation process, the deformation body temperature increases remarkably due to friction and deformation. So the cooling is necessary in the region of the die and tools.
文摘Steel has been used as a traditional wheel materials for a long time.Before 1980' s,over 90% wheels were made of steels.Then,the yield strength of wheel steels increased gradually from 240 -350 MPa to 600 MPa or higher.The advanced high strength steels become the main wheel materials.Since 1990's,DP600 has been broadly applied in steel wheels oversea.However,there was little research of application of high strength steel wheels(especially wheel disc) in domestic wheel industrial.In presence, DP600 steel wheel is only developed in FAWSH by using imported CKD.Other domestic steel wheel manufacturers did little work on high strength DP600 wheel discs.Baosteel wheels Co.Ltd.is the first domestic company producing DP600 steel discs and has become the leading company in production of high strength wheel.Because of the high strength of DP600,its formability,springback,and wrinkle have become the keys of the successful application of DP600 steel.In this paper,the metallurgical and mechanical properties are firstly introduced and formation problems of DP600 are described compared to traditional steels.Secondly,FLD analysis has been done.Wrinkle and more springback are recognized.To solve these problems,an optimized solution is designed and the good result is obtained.The test has shown that the fatigue property of steel wheel discs made by DP600 have been greatly improved.
