A Study on Continuous Flax Fibre Reinforced Polypropylene Composite in Stamp Forming Process

2013 ◽  
Vol 22 (4) ◽  
pp. 096369351302200 ◽  
Author(s):  
Wentian Wang ◽  
Adrian Lowe ◽  
Shankar Kalyanasundaram

This study investigates the forming behaviour of flax fibre reinforced polypropylene composites through stamp forming. A real time photogrammetric three dimensional strain measuring system was employed to capture the surface motion and compute strain deformation during forming. Failure mechanisms exhibited in the flax/polypropylene composites at different forming temperatures were determined by visual and microscopical examinations. Fibre fracture was identified as the major failure mode. At a forming temperature of 160 °C, fibre pull out was also observed in addition to fibre fracture. A study of forming modes exhibited at various forming temperatures illustrated that there is an optimal temperature window for forming. A key finding from this work is that the matrix shear deformation can aid in superior forming for this class of material systems.

2014 ◽  
Vol 875-877 ◽  
pp. 423-427 ◽  
Author(s):  
Wen Tian Wang ◽  
Sudharshan Venkatesan ◽  
Anthony Sexton ◽  
Shankar Kalyanasundaram

This paper investigates the effect of process parameters such as Blank Holder Force (BHF) and Feed Rate, on the spring back behavior of a polymer metal laminate (PML) system comprised of aluminum and polypropylene. Specimens were formed over a hemispherical punch in stamp forming process. A novel real time strain measuring system, ARAMIS, was employed to capture the strain evolution during forming. The results of this work indicate that both BHF and feed-rate exert influence in PML spring back behavior. Fundamental correlation between strain evolution during spring back and the shape of the finished part will be presented. A major finding from this work is that aluminum dominates the spring back behavior of PML in stamp forming.


2014 ◽  
Vol 620 ◽  
pp. 83-89 ◽  
Author(s):  
You Juan Ma ◽  
Xiao Wang ◽  
Peng Hui Xu ◽  
Qiang Zhang ◽  
Hui Xia Liu ◽  
...  

Laser-driven flyer micro forming process is a promising microforming technology with the advantage of high efficiency, low cost, high flexibility. A series of experiments are conducted to investigate forming ability of aluminum foil with the thickness of 50μm. The effect of forming temperature and laser energy on forming ability characterized by forming depth, forming accuracy and surface quality is quantitatively analyzed. It is found that forming depth observed through three dimensional topography increases with the enhancement of forming temperature and laser energy. By elevating the forming temperature, the preheated workpiece suffers more homogenous deformation, presenting better forming accuracy. However, a certain degree of deterioration of surface integrity at the forming temperature of 200°C can be attributed to the earlier appearance of micro cracks caused by excessive thinning even at low laser energy. Overall, it is concluded that the optimal forming temperature is appropriately 150°C as the forming depth and forming accuracy is improved with no deterioration of the surface integrity.


2008 ◽  
Vol 580-582 ◽  
pp. 557-560 ◽  
Author(s):  
J.G. Han ◽  
Kyong Ho Chang ◽  
Gab Chul Jang ◽  
K.K. Hong ◽  
Sam Deok Cho ◽  
...  

Recently, in the loading tests for steel members, the deformation value is measured by calculating a distance of both cross-heads. This measuring method encounters a test error due to various environmental factors, such as initial slip, etc.. Especially, in the case of welded members, the non-uniform deformation behavior in welded joints is observed because of the effect of welding residual stress and weld metal. This is mainly responsible for a test error and a loss of the reliability for used test instruments. Therefore, to improve the accuracy and the applicability of measuring system, it is necessary to employ a visual monitoring system which can accurately measure the local and overall deformation of welded members. In this paper, to accurately measure a deformation of welded members, a visual monitoring system (VMS) was developed by using three-dimensional digital photogrammetry. The VMS was applied to the loading tests of a welded member. The accuracy and the applicability of VMS was verified by comparing to the deformation value measured by a test instrument (MTS-810). The characteristics of the behavior near a welded joint were investigated by using VMS.


2021 ◽  
Vol 11 (12) ◽  
pp. 5461
Author(s):  
Elmedin Mešić ◽  
Enis Muratović ◽  
Lejla Redžepagić-Vražalica ◽  
Nedim Pervan ◽  
Adis J. Muminović ◽  
...  

The main objective of this research is to establish a connection between orthodontic mini-implant design, pull-out force and primary stability by comparing two commercial mini-implants or temporary anchorage devices, Tomas®-pin and Perfect Anchor. Mini-implant geometric analysis and quantification of bone characteristics are performed, whereupon experimental in vitro pull-out test is conducted. With the use of the CATIA (Computer Aided Three-dimensional Interactive Application) CAD (Computer Aided Design)/CAM (Computer Aided Manufacturing)/CAE (Computer Aided Engineering) system, 3D (Three-dimensional) geometric models of mini-implants and bone segments are created. Afterwards, those same models are imported into Abaqus software, where finite element models are generated with a special focus on material properties, boundary conditions and interactions. FEM (Finite Element Method) analysis is used to simulate the pull-out test. Then, the results of the structural analysis are compared with the experimental results. The FEM analysis results contain information about maximum stresses on implant–bone system caused due to the pull-out force. It is determined that the core diameter of a screw thread and conicity are the main factors of the mini-implant design that have a direct impact on primary stability. Additionally, stresses generated on the Tomas®-pin model are lower than stresses on Perfect Anchor, even though Tomas®-pin endures greater pull-out forces, the implant system with implemented Tomas®-pin still represents a more stressed system due to the uniform distribution of stresses with bigger values.


2013 ◽  
Vol 423-426 ◽  
pp. 737-740
Author(s):  
Zhong Yi Cai ◽  
Mi Wang ◽  
Chao Jie Che

A new stretch-forming process based on discretely loading for three-dimensional sheet metal part is proposed and numerically investigated. The gripping jaw in traditional stretch-forming process is replaced by the discrete array of loading units, and the stretching load is applied at discrete points on the two ends of sheet metal. By controlling the loading trajectory at the each discrete point, an optimal stretch-forming process can be realized. The numerical results on the new stretch-forming process of a saddle-shaped sheet metal part show that the distribution of the deformation on the formed surface of new process is more uniform than that of traditional stretch-forming, and the forming defects can be avoided and better forming quality will be obtained.


2014 ◽  
Vol 6 ◽  
pp. 131253 ◽  
Author(s):  
Young-Ho Seo ◽  
Ji-Woo Park ◽  
Woo-Jin Song ◽  
Beom-Soo Kang ◽  
Jeong Kim

Springback in metal forming process often results in undesirable shape changes in formed parts and leads to deterioration in product quality. Even though springback can be predicted and compensated for through the theories or methodologies established thus far, an increase in manufacturing cost accompanied by a change in die shape is inevitable. In the present paper, it is suggested that the cost accompanied with springback compensation can be minimized while allowing the processing of various three-dimensional curved surfaces by using a flexible die composed of multiple punches. With the die being very flexible, the iterative trial-and-error method can be readily applied to compensate for the springback. Thus, repeated designing and redesigning of solid or matched dies can be avoided, effectively saving considerable time. Only some adjustments of punch height are required. Detailed designs of the flexible die as well as two core algorithms to control the respective punch heights are described in this paper. In addition, a closed-loop system for the springback compensation using the flexible die is proposed. The amount of springback was simulated by a finite element analysis and the modified displacement adjustment (DA) method as the springback compensation model was used in the closed-loop system. This system was applied to a two-dimensional quadratic shape problem, and its robustness was verified by an experiment.


2014 ◽  
Vol 906 ◽  
pp. 167-177 ◽  
Author(s):  
Hou Lei Gan ◽  
Lei Tian ◽  
Chang Hai Yi

Abstract: The Interface of sisal fiber which was treated by using alkali, potassium permanganate, atmospheric plasma and silane reinforced polypropylene composites were investigated by single fiber pull-out testes and surface morphology were studied. The results indicated that the morphological changes observed on the sisal fiber surface were obviously evident. Untreated, permanganate and plasma treated sisal fiber reinforced PP show a stable debonding process. Silane treated sisal fiber reinforced PP show an unstable debonding process. Single fiber pull-out tests indicated that the IFSS value was in the order of FIB < FIBKMnO4 < FIBP < FIBKH-550 < FIBKH-570. As can be seen from surface morphology of pull-out fiber, a little of PP resin was adhered to the pull-out FIB, FIBKMnO4, FIBP of sisal fiber. In contrast, PP resin at the surface of pull-out fiber was flaked off and sisal fibril was drawn out from sisal fiber were observed from pull-out fibers of FIBKH-550 and FIBKH-570.


Author(s):  
Shiyong Yang ◽  
Kikuo Nezu

Abstract An inverse finite element (FE) algorithm is proposed for sheet forming process simulation. With the inverse finite element analysis (FEA) program developed, a new method for concurrent engineering (CE) design for sheet metal forming product and process is proposed. After the product geometry is defined by using parametric patches, the input models for process simulation can be created without the necessity to define the initial blank and the geometry of tools, thus simplifying the design process and facilitating the designer to look into the formability and quality of the product being designed at preliminary design stage. With resort to a commercially available software, P3/PATRAN, arbitrarily three-dimensional product can be designed for manufacturability for sheet forming process by following the procedures given.


Author(s):  
Hossein Ghorbani-Menghari ◽  
Mehrdad Azadipour ◽  
Mehran Ghasempour-Mouziraji ◽  
Young Hoon Moon ◽  
Ji Hoon Kim

The deformation machining process (DMP) involves machining and incremental forming of thin structures. It can be applied for manufacturing products such as curved-surface blades without using 5-axis computerised numerical control machines. This work presents the effect of tool diameter and forming temperature on spring-back and dimensional accuracy of a simple fabricated part. The results of the first phase of the study are utilised to design the fabrication process of a curved surface blade. A feature-based algorithm is used to design the tool path for the forming process. The dimensional accuracy of the final product is improved through warm forming, two-point incremental forming, and extension of the bending zone to the outside of the product edges. The results show that DMP can be used to fabricate complex curved-surface workpieces with acceptable dimensional accuracy.


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