High-Performance Solid-State Supercapacitors Fabricated by Pencil Drawing and Polypyrrole Depositing on Paper Substrate

A solid-state powerful supercapacitor(SC) is fabricated with a substrate of Xerox paper. Its current collector based on a foldable electronic circuit is developed by simply pencil drawing. Thin graphite sheets on paper provide effective channels for electron transmission with a low resistance of 95 X sq-1. The conductive organic material of polypyrrole coated on thin graphite sheets acts as the electrode material of the device. The as-fabricated SC exhibits a high specific capacitance of 52.9 F cm-3at a scan rate of 1 m V s-1. An energy storage unit fabricated by three full-charged series SCs can drive a commercial light-emitting diode robustly. This work demonstrated a simple, versatile and costeffective method for paper-based devices.

Formation of Aluminum-magnesium Alloy Cup by Hydrodynamic Deep Drawing with Twin-loading Paths

In order to overcome the limitation of hydro-rim deep drawing, a new process of hydrodynamic deep drawing （HDD） with independent radial hydraulic pressure was proposed. By employing the dynamic explicit analytical software ETA/DynaformS.5 which is based on LS-DYNA3D, the effects of independent radia! hydraulic pressure on the stress, strain and the sheet-thickness of aluminum-magnesium cylindrical cup with a hemispherical bottom were analyzed by numerical simulation. The feature of stress distribution is that there exists a stress-dividing circle in the flange, and the radius of dividing circle was determined by theoretical analysis and stimulation. The experimental results indicate that the reasonable match of independent radial hydraulic pressure and liquid chamber pressure can effectively reduce the thinning at the bottom of hemisphere, decrease the radial stress-strain, and improve the drawing limit of aiuminum-magnesium alloy cylindrical cup.

Key technologies of numerical simulation of cup hydrodynamic deep drawing

A math formula about the relation between fluid pressure after overflowing and punch stroke that can be applied in general FEM software was proposed. It is proved that theoretical results keep coincident to experimental results and the method to simulate hydrodynamic deep drawing process that integrates general FEM software with mathematical description is feasible. [

Integral as a Function of the Upper Limit to Solve Axial Symmetrical Rod Drawing and Extrusion

A kinematically admissible velocity field which is different from Avitzur's has been proposed for axial symmetrical rod drawing and extrusion.An upper-bound analytical solution in cylindrical coordinates has been obtained without any mathematical simplification in this paper.

Numerical Analysis of Hydroforming Deep Drawing of Conical Cup

Aided by the FE-code. analysis is carried to find the proper hydroforming deep-drawing condition for the perfect forming of a conical cup that can not be drawn successfully by conventional deep drawing method. Hydraulic counter pressure must be reasonably controlled, otherwise defects such as fracture and wrinkling can not be avoided. Therefore, the forming procedure is divided into three stages, and the counter pressure is adjusted intentionally to make the blank clamped onto the punch at a suitable time, then deformation at dangerous area is resisted by the effect of the counter pressure and the conical cup can be formed without defects.

Numerical simulation of cup hydrodynamic deep drawing

The simulation of hydrodynamic deep drawing by means of FEM is an efficient method that can relieve experimental burden and find the optimum process parameters. Some problems such as mathematical description of cavity liquid flow pressure must be solved firstly. A math formula about hydrodynamic flow pressure that can be applied in general FEM software was proposed, and good results were gained. It was proved that the theoretical results keep coincident with experimental results.[

EMF CHANGES MADE BY COLD DRAWING AND HEATING TREATMENT IN TYPE K HEAVY-GAUGE SHEATHED THERMOCOUPLE CABLES

The electromotive force (EMF) changes in type K heavy gauge sheathed thermocouple cables was investigated. To cope with this discrepancy owing to EMF steep reduction and understand the difference between type K heavy gauge sheathed thermocouple cables and small ones, the affects of EMF from sheath pipe, drawing times, annealing temperature, annealing time and annealing way were mainly studied and appropriately analyzed. The results show the change in the thermal EMF is related with the residual stress and crystal defects, which are imparted by cold work during manufacture. The affects of cold work can be removed by annealing. Finally, a feasible way of fabricating heavy gauge sheathed thermocouples was suggested according to practical situation.

WORKING LIQUID PRESSURE AND ITS CONTROL IN HYDRAULIC DRAWING PROCESSES OF CUPS

A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. And a set of pressure controlling devices with PLC as a central processor are designed. It can be got from the relevant experiments that the pressure-stroke characteristic is correct and its control for forming process is available.

Product Drawing Management System Based on Group Technology

With the development and widely used of the compute r technology, the CAD has been more and more used in the process of designing prod uct. The number of the engineering drawings will greatly increase because of the continually appearance of the new products. As a result, it has become a badly needed to be solved problem for us that how to rapidly and efficiently search an d appropriately preserve and manage the drawings. In this paper, a method of bui lding the product drawing management system for extrusion aluminum-type materia ls is discussed. This system is designed for the profile graphic of the aluminou s section material management by using Group Technology (GT) principle. Accordin g to the GT, we developed a classifying-coding system and drawing management sy stem about the extrusion aluminum-type materials through analyzing a large numb er of extrusion aluminum-type materials section drawings. The coding system has realized the flexible coding and hidden coding of the extrusion aluminum-type materials and then enhanced the flexibility and the expansible of the system. By supplying the designer with the human-computer interaction interface the drawi ng management system has been able to resolve many difficult problems such as se arch and manage the existed drawings about the extrusion aluminum-type material s very well. At the same time, it also helps the developing work enhance the abi lity of inheriting by applying this kind of variant method. In a word, with the help of this system we can not only shorten the designing time greatly and reduc e the cost of the product but also research the designing drawings rapidly. In o rder to output the data information related to the part drawing, the system uses the data-exchange standard to which the drawing support-software adapted as d ata-exchange interface. The system is advantageous to building a standard of dr awing design and increasing the efficiency of searching drawing and enhancing th e information management, which have had a base for building the best management system in the future. In addition, the paper has a detailed analysis about the principle of flexible classification code and data structure.

Prediction and Control of Both Wrinkle Limit and Fracture Limit on Cylindrical Cup Deep-Drawing

hased on both the wrinkle model and fracturc model, the wrinkle critical tangent pressure and the fractureon critical radial tensile stress are calculated respectively. The maximum tangent pressure formula in the flange deformation zone and the maximum radial tensile stress formula in the cylinder-wall pass force zone are given, and both theno-wrinkle limitl criterion and no-fracture limit criterion are put froward. The prediction and control criterion anddiagram of both the wrinkle limit and fracture limit on cylindrical cup deep-drawing, the most suitable formingzone and the limit deep-drawing coefficient are obtained. Comparing with present experience formulae and actualproduct's production, this prediction and control are quite accurate.

Theoretical and Experimental Analysis of Deep Drawing Cylindrical Cup

There are mainly two methods of deep drawing analysis: experimental and analytical/numerical. Experimental analysis can be useful in analyzing the process to determine the process parameters that produce a defect free product, and the analytical/numerical modeling can be used to model and analyze the process through all stages of deformation. This approach is less time consuming and more economical. Sheet metal forming often includes biaxial in-plane deformation with non-proportional strain paths. In deep drawing of cylindrical cup, the deformation in the flange is dominated by pure shear deformation, while it changes to plane strain when the material is drawn into the die. This paper deals with the analysis of deep drawing of circular blanks into axi-symmetric cylindrical cup using numerical modeling. The blank drawability has been related both theoretically and experimentally with the initial diameter of the blank and deep drawing parameters. The strains in the radial and circumferential directions have been measured. A correlation on the flange thickness variation by taking into account the work hardening with the analytical and experimental values also has been searched.

Prediction of mechanical properties for deep drawing steel by deep learning

At present,iron and steel enterprises mainly use“after spot test ward”to control final product quality.However,it is impossible to realize on-line quality predetermining for all products by this traditional approach,hence claims and returns often occur,resulting in major eco-nomic losses of enterprises.In order to realize the on-line quality predetermining for steel products during manufacturing process,the predic-tion models of mechanical properties based on deep learning have been proposed in this work.First,the mechanical properties of deep drawing steels were predicted by using LSTM(long short team memory),GRU(gated recurrent unit)network,and GPR(Gaussian process regression)model,and prediction accuracy and learning efficiency for different models were also discussed.Then,on-line re-learning methods for transfer learning models and model parameters were proposed.The experimental results show that not only the prediction accuracy of optimized trans-fer learning models has been improved,but also predetermining time was shortened to meet real time requirements of on-line property prede-termining.The industrial production data of interstitial-free(IF)steel was used to demonstrate that R2 value of GRU model in training stage reaches more than 0.99,and R2 value in testing stage is more than 0.96.

Deep drawing of cup shell by powder cavity flexible forming technology

A forming method named powder cavity flexible forming was proposed. It is a forming technology which uses powder medium instead of rigid punch or die to form sheet metals. Cup shells were successfully obtained by this technology. The theoretical calculation equation of forming load was obtained through mechanical analysis and the stress state in cup shells was analyzed by finite element simulation. The results show that powder cavity flexible forming technology can improve the forming limit of sheet metal. Compared with rigid die forming process, the thickness reduction in the punch fillet area significantly decreases and the drawing ratio increases from 1.8 to 2.2. The thinning compressive stress in the bottom of cup shell emerges, which makes the bottom of the cup shell in three-dimensional stress state and the stress in punch fillet region decrease due to powder reaction force, which can effectively inhibit the sever thinning of the sheet and prevent the generation of fracture defects.

THE INTEGRAL AS A FUNCTlON OF THE UPPER LIMIT AND DEPENDING ON A PARAMETER TO SOLVE DRAWING THROUGH IDLING ROLLS

The relocity and sirain-rate .field which are different from Avilzur's have beenestablished in Caitesian coordinates. Using the integral as a function of the upper limitand integration depending on a parameler, an analylical upper-bound solution todrawing stress through idling rolls has been obtained in this paper.

Formability improvement and blank shape definition for deep drawing of cylindrical cup with complex curve profile from SPCC sheets using FEM

In the current work,to predict and improve the formability of deep drawing process for steel plate cold rolled commercial grade(SPCC) sheets,three parameters including the blanking force,the die and punch corner radius were considered.The experimental plan according to Taguchi's orthogonal array was coupled with the finite element method(FEM) simulations.Firstly,the data from the test of stress-strain and forming limit curves were used as input into ABAQUS/Explicit finite element code to predict the failure occurrence of deep drawing process.The three parameters were then validated to establish their effects on the press formability.The optimum case found via simulation was finally confirmed through an experiment.In order to obtain the complex curve profile of cup shape after deep drawing,the anisotropic behavior of earring phenomenon was modeled and implemented into FEM.After such phenomenon was correctly predicted,an error metric compared with design curve was then measured.

PREDICTION AND CONTROL OF BOTH WRINKLE AND FRACTURE LIMITS ON CYLINDRICAL CUP MULTI DEEP DRAWING

Based on the superfluous triangle material wrinkle model,the no wrinkle limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the wrinkle limit.According to fracture model,the no fracture limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the fracture limit.Combining the no wrinkle limit criterion with the no fracture limit criterion,the no wrinkle and no fracture limit criterion and diagram on cylindrecal cup multi deep drawing are given as the prediction and control of both wrinkle and fracture limits.In accordance with this can determine the limit deep drawing coefficient and minimum deep drawing coefficient,and can choose the deep drawing coefficient of multi deep drawing,blank holder force and deformation force by optimization choice method.Theory calculation and test data are highly consistent,and suitable for no flange multi deep drawing,flange multi deep drawing and rigid punch expanding

Prediction and Control of both Wrinkle Limit and Fracture Limiton Cylindrical Cup Deep-drawing(Ⅱ)

The prediction and control criterion of both the wrinkle limit and fracture limit on the cylindrical cup deep-drawing are given, and the prediction and control diagram of both the wrinkle limit and fracture limit are also given. The results show that it is suitable for no-flange cylindrical cup deep-drawing, narrow-flange cylindrical cup deep-drawing, wide-flange cylindrical cup deep-drawing/expanding compound forming and rigid punch expanding forming.

Determination of a Drawing Die's Cone Angle at a Small Compression Ratio Based on the Upper Bound Theory

The value of a drawing die＇s cone angle has great influence on wire drawing. In order to determine the optimum value of a drawing die＇ s cone angle, the plastic deformation power Wi, shear deformation power Wi and friction power of contact surface Wf were calculated using the upper bound theory with a reasonable and movement permitted velocity field according to the related characteristics. Then the relation between half cone angle and unit drawing force was obtained and it was compared with the result with the spherical velocity field. The relative error of the two near the optimal value is only about 0. 26% through comparing with existing calculated results. Finally, in an ABAQUS environment the finite element modal of the wire rod with 12. 5 mm diameter in first drawing pass was established and the axial drawing force in different cone angles was obtained using the ABAQUS/Explicit explicit integration method. The finite element method （FEM） results verify the results using the upper bound theory and this indicated that the velocity field and the relation between half cone angle and unit drawing force reasonable.

Site Selection of Waste Slag Yard and Design of Protective Measures in Water Supply Project of Drawing from the Songhua River in Central Cities of Jilin

Water supply project of drawing from the Songhua River in central cities of Jilin is taken as research object.On the basis of analyzing project characteristics and natural conditions of the project area,site selection of waste slag yard of water diversion project and design of water and soil conservation measures are discussed.Rationality of site selection of waste slag yard and pertinence of prevention and control measures of water and soil loss in waste slag yard are analyzed,and comprehensive utilization of waste slag in large-scale production and construction projects is explored.

THE INTEGRAL AS A FUNCTION OF THE UPPER LIMIT AND AN ANALYTICAL SOLUTION TO PLANE STRAIN DRAWING AND EXTRUSION

A kinematically admissible velocity field which is different from Avitzur's is established in Cartesian Coordinates. An upper-bound analytical solution to strip drawing andextrusion is obtained by using the integral as a function of the upper limit in this paper.