The Sequential Analysis of Film Deformation Behavior during Successive Biaxial Stretching Process

2013 ◽  
Vol 747 ◽  
pp. 611-614 ◽  
Author(s):  
Yoshiyuki Kushizaki ◽  
Masayoshi Tokihisa ◽  
Hideki Tomiyama ◽  
Toshiro Yamada
Keyword(s):  
Constitutive Equation ◽  
Deformation Behavior ◽  
Draw Ratio ◽  
Sequential Analysis ◽  
Machine Direction ◽  
Material Constants ◽  
Biaxial Stretching ◽  
Experimental Deformation ◽  
Stretching Ratio ◽  
Stretching Process

The deformation behavior of Polypropylene (PP) film during successive biaxial stretching process which consists of machine direction (MD) stretching process with a roll drawing and transverse direction (TD) stretching with a tentering was analyzed sequentially by using a finite element method (FEM). In order to analyze it, stress-strain curves of casted PP film and uni-axially oriented PP film in MD were measured and fitted into the constitutive equation that the authors developed previously, respectively, and then, material constants for both films were obtained. Deformation behavior during successive biaxial stretching were calculated by applying the constitutive equation with the material constants of casted PP film for MD stretching and uni-axially oriented PP film in MD for TD stretching, respectively. Analytical conditions were the draw ratio of 5 for MD analysis and the stretching ratio of 9.5 for TD analysis. The authors also experimentally measured the thickness of film during and after MD and TD stretching using a pilot plant under the same conditions as analytical condition. Calculated results were able to express qualitatively the experimental deformation behavior of PP film such as the neck-in phenomena during MD stretching and the change of film thickness during MD and TD stretching.

Structure and Mechanical Properties of Porous Ultra-High Molecular Weight Polyethylene

2012 ◽  
Vol 466-467 ◽  
pp. 332-335 ◽  
Author(s):  
Jiu Mei Xiao
Keyword(s):  
Draw Ratio ◽  
Mechanical Test ◽  
Longitudinal Direction ◽  
Test Results ◽  
Machine Direction ◽  
Elongation At Break ◽  
Wet Process ◽  
Biaxial Stretching ◽  
Lower Elongation ◽  
Ultra High Molecular Weight

The porous UHMWPE were prepared by wet process and biaxial stretching. The scanning electron microscopy (SEM) experimental results indicated that there were two discernible components: microfibril bundles and microfibril networks in the porous biaxial UHMWPE. The higher draw ratio along the longitudinal direction (the machine direction) contributed more to orientation of the UHMWPE fibrils. Along the transverse direction, fibrils were torn, and more microfibrils network with larger size formed. The mechanical test results showed that along the longitudinal direction, the UHMWPE exhibited higher tensile strength and lower elongation-at-break.

Establishment of an ANSYS-Based Constitutive Modeling for Age Forming of Aluminum Alloy

2012 ◽  
Vol 217-219 ◽  
pp. 1497-1500 ◽  
Author(s):  
Xiao Jun Zuo ◽  
Jun Chu Li ◽  
Da Hai Liu ◽  
Long Fei Zeng
Keyword(s):  
Aluminum Alloy ◽  
Constitutive Equation ◽  
Material Model ◽  
Tensile Tests ◽  
Material Constants ◽  
Tensile Process ◽  
Simulation Based ◽  
Optimal Material ◽  
Two Stages ◽  
Good Agreement

Constructing accurate constitutive equation from the optimal material constants is the basis for finite element numerical simulation. To accurately describe the creep ageing behavior of 2A12 aluminum alloy, the present work is tentatively to construct an elastic-plastic constitutive model for simulation based on the ANSYS environment. A time hardening model including two stages of primary and steady-state is physically derived firstly, and then determined by electronic creep tensile tests. The material constants within the creep constitutive equations are obtained. Furthermore, to verify the feasibility of the material model, the ANSYS based numerical scheme is established to simulate the creep tensile process by using the proposed material model. Results show that the creep constitutive equation can better describe the deformation characteristics of materials, and the numerical simulations and experimental test points are in good agreement.

Hot Compression Deformation Behavior of Spray-Formed AlSn20Cu Alloy

2021 ◽  
Vol 1035 ◽  
pp. 189-197
Author(s):  
Bao Ying Li ◽  
Bao Hong Zhu
Keyword(s):  
Constitutive Equation ◽  
Strain Rate ◽  
Deformation Behavior ◽  
Deformation Temperature ◽  
Phase Distribution ◽  
True Stress ◽  
Hot Compression ◽  
Test Machine ◽  
Hot Compression Deformation ◽  
Compression Deformation

The hot deformation behavior of spray-formed AlSn20Cu alloy during hot compression deformation was studied, and the constitutive equation of AlSn20Cu alloy was established. The samples of spray-formed AlSn20Cu alloy were compressed on Gleeble-3500 thermal simulation test machine. The error of the true stress caused by adiabatic heating effect in the experiment was corrected. The constitutive equation of spray-formed AlSn20Cu alloy could be represented by Zener-Hollomon parameter in a hyperbolic sine function. The results showed that the deformation temperatures and strain rates had a notable effect on the true stress of the alloy. At the identical deformation temperature, the true stress increased with the increase of strain rate. When the strain rate was constant, the stress decreased with the increase of deformation temperature. After hot compression deformation, the tin phase was elongated along the direction perpendicular to the compression axis with short strips and blocks. With the increase of deformation temperature and the decrease of strain rate, Sn phase distribution became more homogeneous.

Physical properties of biaxially oriented PA6 film for simultaneous stretching and sequential processing

2011 ◽  
Vol 31 (1) ◽  
Author(s):  
Masao Takashige ◽  
Toshitaka Kanai
Keyword(s):  
Impact Strength ◽  
Physical Properties ◽  
Physical Property ◽  
High Impact ◽  
Thermal Shrinkage ◽  
Double Bubble ◽  
Biaxial Stretching ◽  
High Impact Strength ◽  
The Difference ◽  
Stretching Process

Abstract There are two different stretching processes that produce the biaxially oriented film, namely the tenter process and double bubble tubular film process. Furthermore, there are two tenter processes, i.e., the sequential biaxial stretching process and simultaneous biaxial stretching process. There is no report describing the difference among film physical properties of the three different processes. The biaxially oriented polyamide film using the double bubble tubular process has good balanced physical property and high impact strength, thus it is used for proper applications utilizing their advantage properties. In this report, the influence of each biaxial stretching process on film physical properties of polyamide, which has hydrogen bond, was studied in detail. As a result, the tentering process film has anisotropic tensile properties between machine direction (MD) and transverse direction (TD). This result was influenced by a later stretching process, namely TD stretching. On the contrary, the double bubble tubular film has good balanced properties, especially thermal shrinkage and impact strength. Tentering simultaneous stretching film has much larger shrinkage in MD than in TD. The sequential stretching film has larger shrinkage in TD than in MD. The double bubble tubular film has high impact strength, because it corresponds to the balanced molecular orientation.

Characterization of High Temperature Deformation Behavior of BFe10-1-2 Cupronickel Alloy Using Orthogonal Analysis

2017 ◽  
Vol 36 (7) ◽  
pp. 701-710
Author(s):  
Jun Cai ◽  
Kuaishe Wang ◽  
Xiaolu Zhang ◽  
Wen Wang
Keyword(s):  
High Temperature ◽  
Flow Stress ◽  
Constitutive Equation ◽  
Strain Rate ◽  
Deformation Behavior ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Compression Tests ◽  
Statistical Parameters ◽  
Orthogonal Analysis

AbstractHigh temperature deformation behavior of BFe10-1-2 cupronickel alloy was investigated by means of isothermal compression tests in the temperature range of 1,023~1,273 K and strain rate range of 0.001~10 s–1. Based on orthogonal experiment and variance analysis, the significance of the effects of strain, strain rate and deformation temperature on the flow stress was evaluated. Thereafter, a constitutive equation was developed on the basis of the orthogonal analysis conclusions. Subsequently, standard statistical parameters were introduced to verify the validity of developed constitutive equation. The results indicated that the predicted flow stress values from the constitutive equation could track the experimental data of BFe10-1-2 cupronickel alloy under most deformation conditions.

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