SIMULATION OF FINAL DIRECT EXTRUSION STAGE FOR LARGE RODS WITH LOW EXTRUSION RATIO

2018 ◽  
pp. 48-55
Author(s):  
V. R. Kargin ◽  
A. Yu. Deryabin
Keyword(s):  
Defect Formation ◽  
Cone Angle ◽  
Metal Flow ◽  
Joint Effect ◽  
Extrusion Ratio ◽  
Contact Friction ◽  
Extrusion Force ◽  
Direct Extrusion ◽  
Negative Effect ◽  
Edge Temperature

The direct extrusion of large 7075 alloy bars 188, 214, 252, 283, 326, 560 mm in diameter was simulated with 0 and 0,5 friction coefficients, 80° and 90° die cone angles from the 800 mm diameter container at the 200 MN press using the DEFORM-2D software package. It provided the distribution of metal flow radial velocities on the dummy block working surface versus the contact friction value, die cone angle and extrusion ratio factor at the main and final stages of extrusion. Butt-end height at the beginning of back-end extrusion defect formation was taken equal to a distance between the dummy block plane and the plane of extruded metal feeding into flat or cone die openings. The joint effect of the extrusion ratio factor, friction coefficient and die cone angle on the butt-end height, extrusion force, deformation and stress intensity factors, and die opening edge temperature was studied. Numerical experiments were performed based on the 23 complete factorial design for the following parameter variability intervals: Х1 = 3÷9, Х2 = 0÷0,5, Х3 = 80÷90°. Friction between the tool and the blank at the final extrusion stage has a negative effect due to a noticeable radial velocity reduction. This leads to the earlier initiation of central back-end extrusion defect formation. Extrusion into the conical die and increasing the extrusion ratio factor, on the contrary, speeds up radial flow velocity and ensures that the back-end extrusion defect starts forming later. The main factor that determines butt-end height is the extrusion ratio factor. A mathematical model is proposed to select the butt-end thickness for specific conditions of extruding large bars with low extrusion ratios.

Researches on a Composite Extrusion Approach Based on FEM Method and Experiments

2011 ◽  
Vol 686 ◽  
pp. 305-309 ◽  
Author(s):  
Ding Fei Zhang ◽  
Jun Ping Zhang ◽  
Hong Jun Hu
Keyword(s):  
Mechanical Properties ◽  
Element Model ◽  
Az31 Alloy ◽  
Extrusion Ratio ◽  
Extrusion Force ◽  
Direct Extrusion ◽  
Fem Method ◽  
Shear Process ◽  
Different Temperatures ◽  
Microstructures And Mechanical Properties

This paper deals with a finite element model (FEM) for the extrusion of AZ31 alloy and extrusion experiments at different temperatures. The simulation is utilized to predict the extrusion force and strain at different temperatures. ES (extrusion-shear) process and direct extrusion are investigated at 370, 400 and 420°C to discuss the effects of different temperatures on the microstructures and mechanical properties with the extrusion ratio of 11.56. The simulation results obtained show that the extrusion force of ES process is much larger than direct extrusion because of the two corners. ES process could effectively refine the grains, especially the microstructure of the central region compared with direct extrusion. The bar extruded at 370°C shows the best microstructures and mechanical properties.

Will rivals enter or wait outside when faced with litigation risk? Patent litigation in complex product industries and international market entry

2021 ◽  
pp. 147612702199825
Author(s):  
Ergun Onoz ◽  
Claudio Giachetti
Keyword(s):  
Market Entry ◽  
International Market ◽  
Joint Effect ◽  
Litigation Risk ◽  
Patent Litigation ◽  
Complex Product ◽  
Patent Strategy ◽  
Negative Effect ◽  
Rival Firms ◽  
The Relationship

A spiral of patent infringement litigation among rival firms is a phenomenon often observed in complex product industries, where products comprise numerous separately patentable elements. Theoretically grounded in the awareness–motivation–capability framework of competitive dynamics, this article contributes to the literature on patent strategy and international market entry by looking at how, in a complex product industry, the intensity of patent litigation in a country affects a firm’s decision to enter that country. Our results show that the intensity of patent litigation in a country is a deterrent for potential entrants and has a negative effect on a firm’s likelihood of entering that country. We also show that a firm’s previous experience with patent litigation ( awareness component), the share of a firm’s current patent applications in a target country ( motivation component), and the size of a firm’s patent stock ( capability component) moderate the relationship between a country’s patent litigation intensity and a firm’s likelihood of entering that country. We thus shed light on the joint effect of macro- and micro-level patent-related variables on a firm’s market entry decisions. We test our hypotheses with a comprehensive panel of patenting and entry strategies of 84 mobile phone vendors and their patent litigation battles in 45 countries, from 2003 to 2015.

Hydrostatic Extrusion With Controlled Follower Block Clearance

1975 ◽  
Vol 97 (1) ◽  
pp. 25-31 ◽  
Author(s):  
K. M. Kulkarni ◽  
J. A. Schey
Keyword(s):  
Ambient Temperature ◽  
Surface Finish ◽  
Extrusion Ratio ◽  
Hydrostatic Extrusion ◽  
Extrusion Force ◽  
Processing Conditions ◽  
Surface Processing ◽  
Specimen Diameter ◽  
Lubricant Viscosity ◽  
Breakthrough Pressure

Hydrostatic extrusion of annealed 1100 aluminum was investigated experimentally at ambient temperature. The principal variables studied were lubricant viscosity which was varied from less than 100 to over 76,000 SUS at 100 deg F and the diametral clearance between the follower block and the extrusion cylinder which ranged from 0.0005 to 0.0030 in. for the 1.026 in. dia. cylinder. The specimen diameter was 0.97 or 1.00 in. corresponding to an extrusion ratio of 4.75 or 5.00, respectively. The included die angle was either 60 deg or 90 deg. The results show that with a proper combination of the lubricant viscosity and the follower block clearance, hydrostatic extrusion can be accomplished without the necessity of any sealing of the container on the follower block side. The optimum clearance for minimum breakthrough pressure increases as the lubricant viscosity increases. The extrusion force increases with die angle. The paper discusses the various factors that affect the magnitude of the breakthrough pressure and the occasional uneven bamboo-type appearance of the surface. Processing conditions must be selected carefully since the lowest extrusion force does not necessarily lead to a product with the best surface finish.

Understanding T-Ingot Horizontal DC Casting Using Process Modelling

2006 ◽  
Vol 519-521 ◽  
pp. 1461-1466 ◽  
Author(s):  
André Larouche ◽  
Malcom Lane ◽  
Massimo DiCiano ◽  
Daan M. Maijer ◽  
Steve CockCroft ◽  
...  
Keyword(s):  
Process Model ◽  
Defect Formation ◽  
Metal Flow ◽  
Casting Process ◽  
Production Costs ◽  
Process Characteristics ◽  
Powerful Approach ◽  
Foundry Alloys ◽  
Dc Casting

Horizontal continuous casting process has been successfully implemented in Alcan for the production of T-ingots of primary aluminium and foundry alloys. Ability to achieve increased productivity targets and reduce production costs relies on a fundamental understanding of key process characteristics and operating parameters. Thanks to the long-standing experience in vertical DC Casting, numerical modelling appeared as a powerful approach to understand phenomena related to metal flow, solidification and ultimately defect formation. As part of a collaborative R&D program, a global model of horizontal casting process, integrating specialized sub-models on critical aspects of the process such as meniscus dynamics, is being developed. Experimental characterization of primary and secondary cooling is performed in parallel with modelling work to provide the information necessary to properly characterize mould heat transfer. This paper will present the development of a 3D process model of T-ingot casting along with its application to solve specific process challenges that have emerged during the first years of production in the plant.

scholarly journals Business Strategy, Accounting Conservatism and Performance

2020 ◽  
Vol 9 (2) ◽  
pp. 23
Author(s):  
Han Li
Keyword(s):  
Corporate Governance ◽  
Financial Performance ◽  
Internal Control ◽  
Business Strategy ◽  
Joint Effect ◽  
Accounting Conservatism ◽  
Governance Mechanism ◽  
Negative Effect ◽  
Corporate Governance Mechanism ◽  
And Performance

This research consists with prior business strategy typology and accounting conservatism theories. It investigates the joint effect of business strategy and accounting conservatism on the firm’s financial performance. The paper finds that accounting conservatism as a prudent accounting reporting principle plays an important corporate governance mechanism. The conservatism can mitigate the negative effect of the aggressive business strategy. The joint effect between business strategy and accounting conservatism is positively related with financial performance. The result is robustness when the different measurements of the strategy and the conservatism are applied. When the firm has weak internal control quality, the joint effect on financial performance also exists significantly.

scholarly journals A cukorbetegség és a daganatos thrombocytosis túlélésre gyakorolt hatásának vizsgálata emlőtumoros nőkben

2019 ◽  
Vol 160 (51) ◽  
pp. 2012-2020
Author(s):  
Anikó Somogyi ◽  
Magdolna Herold ◽  
Júlia Lohinszky ◽  
László Harsányi ◽  
Zoltán Herold
Keyword(s):  
Breast Cancer ◽  
Type 2 Diabetes ◽  
Joint Effect ◽  
Diabetic Patients ◽  
Breast Cancer Patients ◽  
Negative Effect ◽  
T1 Stage ◽  
The University ◽  
Study Participants

Abstract: Introduction: Thrombocytosis and type 2 diabetes have negative effect on the survival of tumor patients. Previously, their joint effect has not been studied in breast cancer. Aim: The aim of our retrospective study was to investigate the occurrence and effects of thrombocytosis and/or type 2 diabetes in breast cancer patients who attended the 2nd Department of Internal Medicine or the 1st Department of Surgery, Semmelweis University, between 2014 and 2017. Laboratory and anamnestic data were compared at the time of tumor diagnosis between diabetic and non-diabetic groups. Survival analysis was performed to study the effects of thrombocytosis and/or type 2 diabetes. Method: 274 study participants were followed until 31 December 2018, or until their last appearance at the University, or until their death. Results: 5% of the patients had elevated platelet counts (over 400 G/L), and 52 were diabetics. Diabetics were significantly older (non-diabetics: 56.8 ± 13.8 years, diabetics: 67.8 ± 11.0 years, p<0.0001). Triple negative subtype (p = 0.0366), and T1 stage (50%) were present more often in non-diabetics. Stage T2 was more common in diabetic patients (51.9%). Type 2 diabetes was associated with a shorter survival time (p = 0.0032). Thrombocytosis did not affect patient survival. Conclusion: At the diagnosis of breast cancer, existing type 2 diabetes is associated with a more severe clinicopathological stage and shorter survival. We recommend that during routine diabetes controls, women should be made aware of the importance of mammography screening. Moreover, diabetes should be considered as a risk factor; after 30 years of age, diabetics should be screened at least every two years. Orv Hetil. 2019; 160(51): 2012–2020.

The Microstructures and Mechanical Properties of Hot-Processed Magnesium Casting Alloys

2006 ◽  
Vol 503-504 ◽  
pp. 775-780 ◽  
Author(s):  
Takeshi Yamaguchi ◽  
Tadayoshi Tsukeda ◽  
Ken Saito ◽  
Yoshihito Kawamura
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Extrusion Direction ◽  
High Strength ◽  
Extrusion Ratio ◽  
Extrusion Temperature ◽  
Tensile Yield Strength ◽  
Extrusion Force ◽  
Casting Alloys ◽  
Magnesium Casting

In order to make the effect of processing clear, AM50A magnesium casting alloys were extruded at various extrusion conditions such as extrusion temperature and extrusion ratio. The mechanical properties of AM50A alloy increased with decreasing extrusion temperature. Tensile yield strength and tensile strength of extruded AM50A alloy were 389MPa and 420MPa respectively when the extrusion temperature was 348K. The microstructure of the extruded magnesium alloy showed large grains stretched to the extrusion direction and fine recrystallized grains. Decreased extrusion temperature resulted in improved strength and decreased elongation with increasing of the degree of work hardens and extrusion force. When the extrusion ratio is high, improvement of strength is prevented by rycrystallization and it was observed as crystal orientation by XRD. The elongation of the extrusion increased with the recrystallization of grains. Every magnesium alloy extruded at low temperature has high strength.

Three-Dimensional Analysis of Extrusion Process Utilizing the Physical Modeling Technique

1993 ◽  
Vol 115 (1) ◽  
pp. 32-40 ◽  
Author(s):  
H. Sofuog˜lu ◽  
J. Rasty
Keyword(s):  
Physical Modeling ◽  
Cone Angle ◽  
Three Dimensional ◽  
Extrusion Process ◽  
Extrusion Ratio ◽  
Modeling Technique ◽  
Modeling Material ◽  
Internal Deformation ◽  
Metal Extrusion ◽  
Deformation Patterns

The purpose of this study was to simulate the metal extrusion processes via three-dimensional physical modeling technique. Plasticine was utilized as the modeling material, while plexiglass was incorporated in the design and fabrication of a labscale extrusion apparatus. The extrusion setup was designed to accommodate dies of different semi-cone angle while also making it possible to change the extrusion ratio R = A0/Af. Cylindrical billets were prepared utilizing alternating layers of two colors of plasticine. Extrusion of cylindrical billets was conducted at three different reduction ratios and three different die angles for each reduction ratio. Dissection of the extruded billets along a centroidal plane revealed the internal deformation patterns which were subsequently utilized for determining the effect of the die angle and extrusion ratio on the state of strain in the final product as well as the required extrusion loads.

scholarly journals On the Direct Extrusion of Solder Wire from 52In-48Sn Alloy

2021 ◽  
Author(s):  
Sergei Faizov ◽  
Aleksandr Sarafanov ◽  
Ivan Erdakov ◽  
Dmitry Gromov ◽  
Alexandra Svistun ◽  
...  
Keyword(s):  
Melting Furnace ◽  
Hydraulic Press ◽  
Extrusion Ratio ◽  
Small Scale ◽  
Production Cycle ◽  
Scale Production ◽  
The Finite Element Method ◽  
Extrusion Speed ◽  
X Ray ◽  
Direct Extrusion

In this article, a technology for producing wire and rod solder from 52In-48Sn alloy has been developed and investigated in the conditions of small-scale production. The use of direct extrusion of wire and rods instead of the traditional technology for producing solder, which includes pressing, rolling and drawing, can significantly reduce the fleet of required equipment. Using only a melting furnace and a hydraulic press, solder wires and rods can be produced in various sizes. Shortening the production cycle allows you to quickly fulfill small orders and be competitive in sales. The article developed a mathematical model of direct extrusion, which allows you to calculate: extrusion ratio, extrusion speed and pressing force. The results of modeling the process of extrusion of wire &empty;2.00 mm and rods &empty;8.0 mm made of 52In-48Sn alloy are presented. The temperature of the solder and the tool is simulation in software QForm based on the finite element method. Experimental results of manufacturing &empty;2.0 mm solder wire and &empty;8.0 mm rods are presented. The microstructure of the direct extruded solder is a eutectic of phases &gamma; and &beta;. Energy-dispersive X-ray spectroscopy (EDS) mapping of the 52In-48Sn alloy showed that the solder obtained by direct extrusion has a uniform distribution of structural phases. The developed technology can be used in the manufacture of wires and rods from other low-melting alloys.

scholarly journals Process modeling of sequential radial-direct extrusion using curved triangular kinematic module

2021 ◽  
Vol 49 (1) ◽  
pp. 56-63
Author(s):  
Natalia Hrudkina
Keyword(s):  
Process Modeling ◽  
Deformation Process ◽  
Metal Flow ◽  
Vertical Component ◽  
Radial Component ◽  
Cold Extrusion ◽  
Direct Extrusion ◽  
Relative Strain ◽  
Power Mode ◽  
Theoretical Results

In this article new engineering calculations such as the value of the relative strain pressure for the combination of a triangular kinematic module with external modules of various configurations are developed. This allowed us to describe qualitatively the nature of the metal flow in the reversal zone before radial extrusion. This made it possible to achieve a decrease in the predicted assessment of the power mode for the deformation process with comparison by the use of rectangular modules. The greatest reduction in the value of the relative strain pressure corresponded to a combination with an adjacent rectangular module (with the missing vertical component CPVF) and can obtain 7-8%. The deviation of the theoretical results in the power parameters of the process by using a triangular kinematic module are 12-15% for a process with a developed flow radial component. The resulting calculations can be used to model new cold extrusion processes.

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