The Experimental Device Design Of Continuous Equal Channel Angular Pressing With Back Pressure

The experimental device design purpose of the continuous equal channel angular pressing machine with back pressure is to realize process of the continuous equal channel angular extrusion under the condition of back pressure.The equal channel angular pressing with back pressure can increase the plasticity of the material,and the plastic deformation can be carried out successively.Also,materials are not easy to break and to obtain a more complete experimental material.At the same time,the powder can be directly solidified into a high density of bulk material.The work of this paper is based on aluminum,magnesium alloy and powder materials,it is grounded on deformation design with variable back pressure of continuous equal channel angular extrusion process,can set the parameters of the main pressure,back pressure,temperature,the number of round trips,etc.The main parameters setting range:the mode locking force 0?2000KN,the extrusion force 0?500KN,the extrusion speed is 0.1?10mm/s,the back pressure 0?50KN,the temperature 0?999?.The experimental device of the continuous equal channel angular pressing machine with back pressure is composed of four parts:machine frame,mold,hydraulic station and electric control device.The frame adopts three-beam and four column closed structure,it have two system:vertical pressure and horizontal pressure system.The vertical pressure system is composed of clamping oil cylinder,upper beam,lower beam,movable cross beam and vertical guide rail;The horizontal pressure system consists of longitudinal beam and extrusion cylinder.Different from the previous whole mould form,extrusion die is divided into two parts,the upper die and the lower die.The locking force produced by the clamping cylinder can ensure the locking of the die to form a closed extrusion cavity,which makes the deformation of the solid state or the powder material to be extruded and formed in a stable way;Two punches(check its strength and stability)are fixed on the punch base of the extrusion cylinder.Firstly,the aluminum alloy material is placed on the inside of the lower die,the upper and lower die are locked by the locking cylinder.The material is kept under certain pressure.Secondly,the hydraulic equipment is provided with the pressure.Then the back cylinder is pressed into the mold cavity.Finally,the material through the bending channel by the left cylinder punching is changed.The hydraulic station adopts the integral design,which is composed of oil tank,oil pipe,actuating element and an oil cylinder.It adopts the integrated assembly method,the structure is simple and compact.Obtains the oil cylinder,the electric motor,the oil pipe and the oil pump parameter through the calculation;According to the experiment,it needs to design the hydraulic principle diagram,and select the hydraulic valve to complete the sequence.Electric control device includes touch screen,button and OMRON CP1E system.Design PLC ladder diagram,set parameters from the touch screen and buttons to control the operation of the extruder.The experimental device and use method of the continuous equal channel angular pressing machine with back pressure include the design of the machine frame from 2D plane to 3D structure assembly,the parameter calculation of hydraulic system and action of electrical control.The experimental device can be used for aluminum,magnesium alloy and powder material under the condition of back pressure to provide experimental means for the study of large plastic deformation,powder solidification and alloying in the process of continuous equal channel angular extrusion.