Evaluation of Periodic Wrinkle during Sheet Press Forming Utilizing Frequency Characteristic of Ultrasonic Wave

2018 ◽  
Vol 382 ◽  
pp. 127-131 ◽  
Author(s):  
Yuji Segawa ◽  
Takuya Kuriyama ◽  
Hiroshi Harada ◽  
Yasuo Marumo ◽  
Tae Kyung Lee ◽  
...  
Keyword(s):  
Ultrasonic Wave ◽  
Frequency Characteristic ◽  
Forming Process ◽  
Reflected Wave ◽  
Trapezoidal Shape ◽  
Press Forming ◽  
Experimental Apparatus ◽  
The Press ◽  
Plate Specimen ◽  
Novel Method

This study suggests a novel method to detect wrinkles using the frequency characteristic of reflected ultrasonic wave. The experimental apparatus was manufactured to simulate the press forming. A plate specimen possessing periodic wrinkles in a trapezoidal shape was also prepared to simulate actual wrinkles during the press forming process. These wrinkles affected the reflected wave of ultrasonic wave. The power spectrum of reflected wave at a frequency of 0.8 MHz was changed by the occurrence of wrinkles. The comparison of the frequency characteristics provided obvious difference between wrinkled and flat specimens. As a result, the present work confirmed that the frequency characteristic of reflected wave would detect the formation of wrinkles.

scholarly journals Combined Effect of Paperboard Thickness and Mould Clearance in the Press Forming Process

BioResources ◽  
2013 ◽  
Vol 8 (4) ◽  
Author(s):  
Ville Leminen ◽  
Panu Tanninen ◽  
Petri Mäkelä ◽  
Juha Varis
Keyword(s):  
Combined Effect ◽  
Forming Process ◽  
Press Forming ◽  
The Press

scholarly journals Effect of mechanical perforation on the press-forming process of paperboard

2019 ◽  
Vol 38 ◽  
pp. 1402-1408
Author(s):  
Ville Leminen ◽  
Panu Tanninen ◽  
Antti Pesonen ◽  
Juha Varis
Keyword(s):  
Forming Process ◽  
Press Forming ◽  
The Press

Application of wheat flour lubricants to the press-forming process

2002 ◽  
Vol 125-126 ◽  
pp. 375-378 ◽  
Author(s):  
Hirofumi Yoshimura ◽  
Shigeyoshi Torikai ◽  
Toshihumi Nishihara ◽  
Toshiji Nonishi ◽  
Naoyoshi Inouchi
Keyword(s):  
Wheat Flour ◽  
Forming Process ◽  
Press Forming ◽  
The Press

Finite element analysis of the press forming process

2017 ◽  
Vol 131-132 ◽  
pp. 767-775 ◽  
Author(s):  
Muhammad Awais ◽  
Joonas Sorvari ◽  
Panu Tanninen ◽  
Teemu Leppänen
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Forming Process ◽  
Element Analysis ◽  
Press Forming ◽  
The Press

Formability of Fiber-Reinforced Thermoplastics in Hot Press Forming Process Based on Friction Properties

2013 ◽  
Vol 554-557 ◽  
pp. 501-506 ◽  
Author(s):  
Ulrich Sachs ◽  
Sebastiaan P. Haanappel ◽  
Bert Rietman ◽  
Rene Ten Thije ◽  
Remko Akkerman
Keyword(s):  
Friction Coefficient ◽  
Fiber Reinforced ◽  
Hot Press ◽  
Forming Process ◽  
Press Forming ◽  
Sliding Mechanism ◽  
The Press ◽  
Hot Press Forming ◽  
Reinforced Thermoplastics ◽  
Fiber Reinforced Thermoplastics

High performance composites are used in commercial applications in a steadily growing degree. This increase of advanced materials is accomponied with the development of fully automated fabrication processes. It aims to drive down the time and costs of the production while ensuring a high quality of the product. This can achieved by considering the process of hot press forming with continuous fiber reinforced thermoplastics. The development of the process is, however, accompanied with a few difficulties, which require more research. For example, composite materials with different architectures, lay-ups, and constituents, show large differences in formability. This research examines the effect of friction on the formability of thermoplastic composites. Both experiments and simulations were conducted. Demonstrator products have been press-formed from laminates with different materials and architectures (UD-carbon PEEK, UD-carbon-PEI, 8hs-glass PPS, 5hs-carbon PEEK and UD-glass PPS), to investigate their effects on formability. Creating a doubly curved shape from a flat laminate requires at least three deformation mechanisms, namely in-plane shear, bending and inter-ply slippage This paper focuses on the sliding mechanism and the corresponding friction. In order to quantify the amount of sliding in the press-formed product, a dot pattern has been applied to both surfaces of the laminate. The slip between the outer plies can be analyzed by means of photogrammetry. Besides, the friction coefficient of each material is measured in a special designed friction test set-up. It can be seen that the composite formability is directly linked to its friction properties. FE simulations of the press-form process will be performed based on the measured material properties, to demonstrate the influence of the materials friction coefficient.

Experimental Assessment of High Temperature Formability of Boron Steel Sheet Manufactured With a Spring Compound Bending Die

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
Yang Li ◽  
Yong-Phil Jeon ◽  
Chung-Gil Kang
Keyword(s):  
Mechanical Properties ◽  
Heating Temperature ◽  
Boron Steel ◽  
Hot Press ◽  
Forming Process ◽  
Steel Sheets ◽  
Press Forming ◽  
Bending Process ◽  
Tension Testing ◽  
Hot Press Forming

Bending behavior occurs in the hot press forming process, resulting in many cases of failure during forming. To address the problem of cracking and improve the formability and mechanical properties of boron steel sheets in the bending process, an experiment has been carried out by using a spring compound bending die. Also, a comparison has been made between the traditional U-bending die and the spring compound bending die with regard to formability. The influence of the parameters for hot press forming such as the heating temperature, punch speed, and die radii on the mechanical properties and microstructure was analyzed by tension testing and metallographic observations.

scholarly journals Press Forming Process of Closed-profile Automotive Parts Without Flange

2014 ◽  
Vol 81 ◽  
pp. 2068-2073 ◽  
Author(s):  
Yuji Yamasaki ◽  
Kazuhiko Higai ◽  
Toyohisa Shinmiya
Keyword(s):  
Forming Process ◽  
Press Forming ◽  
Automotive Parts

An Area Preserving Transformation Algorithm for Press Forming Blank Development

1993 ◽  
Author(s):  
Nirmal K. Nair ◽  
James H. Oliver
Keyword(s):  
Time Complexity ◽  
Linear Time ◽  
Geometric Interpretation ◽  
Surface Geometry ◽  
Forming Process ◽  
Surface Design ◽  
Design Assessment ◽  
Press Forming ◽  
Blank Shape ◽  
Area Preserving

Abstract An efficient algorithm is presented to determine the blank shape necessary to manufacture a surface by press forming. The technique is independent of material properties and instead uses surface geometry and an area conservation constraint to generate a geometrically feasible blank shape. The algorithm is formulated as an approximate geometric interpretation of the reversal of the forming process. The primary applications for this technique are in preliminary surface design, assessment of manufacturability, and location of binder wrap. Since the algorithm exhibits linear time complexity, it is amenable to implementation as an interactive design aid. The algorithm is applied to two example surfaces and the results are discussed.

scholarly journals Effect of Ultrasonic Treatment on Radon Exhalation from Porous Media: An Experimental Case Study

2018 ◽  
Vol 10 (9) ◽  
pp. 3005
Author(s):  
Ling-feng Xie ◽  
Shu-liang Zou ◽  
Xiang-yang Li ◽  
Chang-shou Hong ◽  
Hong Wang ◽  
...  
Keyword(s):  
Porous Media ◽  
Moisture Content ◽  
Ultrasonic Wave ◽  
Linear Correlation ◽  
Experimental Results ◽  
Radon Exhalation Rate ◽  
Exhalation Rate ◽  
Radon Exhalation ◽  
Experimental Apparatus ◽  
Positive Linear Correlation

Radon is internationally recognized as one of the seven seismic precursors. A self-assembly ultrasonic generator and experimental apparatus for radon measurement were utilized to explore the radon exhalation regularities of water-bearing porous media under different ultrasonic intensities. The experimental results showed that there was a coupling relationship among radon exhalation rate, moisture content, and ultrasonic frequency. With the increase of the frequency of the ultrasonic wave, its effect on the promotion of radon exhalation rate was found to be a more obviously positive linear correlation. The radon exhalation rate, which could climb to a maximum value of 0.179 Bq·m−2·s−1 in a naturally air-dried sample, increased at first and then decreased along with increased moisture content. Moreover, this study found that the ultrasonic wave had the most remarkable promoting effects on the radon exhalation rate of porous media with high moisture content, and there is a positive linear correlation between the growth rate of the radon exhalation rate and moisture content. The experimental results could provide a beneficial reference for the continual monitoring of radon in a seismically active belt and an explanation of radon anomalies; however, the proposed experimental model was simplified, so further insights are strictly required for a reliable correlation with the real monitoring of radon in a seismically active belt.

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