Correlation of Barreling Effect with Boundary Friction Coefficient during Upsetting of Various Materials Workpieces under Processing Conditions

2020 ◽  
Vol 992 ◽  
pp. 751-756
Author(s):  
Volodymyr V. Kukhar ◽  
Eduard S. Klimov ◽  
S.M. Chernenko ◽  
E.Yu. Balalayeva
Keyword(s):  
Friction Coefficient ◽  
Boundary Surface ◽  
Functional Relation ◽  
Strain Range ◽  
Height Ratio ◽  
Qualitative And Quantitative ◽  
Linear Dimensions ◽  
Closed Die Forging ◽  
Structural Carbon ◽  
Structural Carbon Steel

The necessity of taking into account the barreling effect at the design of die cavities, and open die and closed die forging processes on the basis of pre-forming of billets by upsetting is shown. The division of ideas about the indices of “bulk” and “linear” barreling (barrel shape), which is determined by the ratio of the bulk and linear dimensions of the workpiece after upsetting by flat dies, was made. The functional relation (correlation) between these indices and the friction coefficient on the boundary surface between flat dies and the upsetted workpiece has been determined. The qualitative and quantitative effect of workpiece dimensions (diameter-to-height ratio), strain range, temperature (conditions of cold and hot processing) and type of forming material (structural carbon steel, some of Cu-grades and Al-grades) on the barreling effect and friction coefficient during upsetting was found. The developed method makes it possible to predict a change in the friction coefficient during the upsetting of various material workpiece under given conditions of forming and to monitor their effect to the final shape.

USS COR-TEN A

Alloy Digest ◽  
1972 ◽  
Vol 21 (11) ◽  
Keyword(s):  
United States ◽  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Atmospheric Corrosion ◽  
Heat Treating ◽  
Steel Composition ◽  
United States Steel Corporation ◽  
Structural Carbon ◽  
Minimum Yield ◽  
Structural Carbon Steel

Abstract USS COR-TEN A, the original COR-TEN Steel composition (see U.S.S. COR-TEN, Alloy Digest SA-17, April 1954), has 5 to 8 times the atmospheric corrosion resistance of structural carbon steel and a minimum yield point of 50,000 psi in sections through 1/2-inch thick. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and compressive and shear strength as well as fracture toughness. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-283. Producer or source: United States Steel Corporation.

Comparison of the μ(I) and HBP models for simulating granular media

2018 ◽  
Vol 29 (07) ◽  
pp. 1850050 ◽  
Author(s):  
Mehran Kheirkhahan ◽  
Khosrow Hosseini
Keyword(s):  
Friction Coefficient ◽  
Failure Mode ◽  
Granular Flow ◽  
Granular Media ◽  
State Equation ◽  
Dam Break ◽  
Harmonic Mean ◽  
Height Ratio ◽  
Viscoplastic Models ◽  
Applied Stresses

Application of Lagrangian meshless methods in modeling granular flow has been a major concern for researchers due to their particular nature. For modeling granular movement, it is assumed that the particles are continuous. The SPHysics code is developed for modeling the movement of Newtonian fluids in which the pressure is derived from the state equation. In this study, [Formula: see text] and Herschel–Bulkley–Papanastasiou (HBP) viscoplastic models are implemented in the SPHysics code to analyze the movement of grains induced by the applied stresses. In the first model, the movement of granular particles is based on the characteristics such as inertia and friction coefficient, and in the second model, the movement is related to the non-Newtonian viscoplastic behavior of fluids. The accuracy of the models is evaluated by simulating the experimental benchmarks for granular dam break. The effect of length-to-height ratio on the failure mode of dam break phenomenon is also investigated. The performance of the models is increased by introducing the gate removal speed and also the harmonic mean of the viscosity instead of the viscosity proper to each particle. This study shows that the models could capture the behavior of grains in the static and the dynamic parts of the mass body.

scholarly journals Behavioral Analysis of Hydrogen in Metals under the Effect of H2S Corrosion Using a Layer-stripping Micro-hardness Technique

2020 ◽  
Vol 26 (3) ◽  
pp. 287-294
Author(s):  
Lei GU ◽  
Jing WANG ◽  
Xiaoyang LI
Keyword(s):  
Hydrogen Sulfide ◽  
Hydrogen Diffusion ◽  
Hardness Test ◽  
Micro Hardness ◽  
Hydrogen Distribution ◽  
Hydrogen In Metals ◽  
H2s Corrosion ◽  
Saturated Layer ◽  
Structural Carbon ◽  
Structural Carbon Steel

In order to study the distribution behavior of hydrogen in metals under the condition of H2S corrosion, a layer-stripping micro-hardness test was designed to analyze the hydrogen distribution along the depth of hydrogen-charged 45 high-quality structural carbon steel at three different hydrogen sulfide concentrations and four corrosion periods in this study. The results show that there is a terminal solid solubility of hydrogen in the metal for hydrogen sulfide solutions over various concentrations and corrosion periods. A hydrogen-saturated layer is produced by hydrogen diffusing through the metal from an unsaturated state to a fully saturated state. The hydrogen-saturated layer is not affected by the concentration of the corrosion, but its thickness increases as the corrosion period increases. In this way, we established a new hydrogen diffusion model in metals.

Synchronic and diachronic analysis of prepositional multiword modifiers across Romance languages

2020 ◽  
Vol 43 (2) ◽  
Author(s):  
Valentina Piunno ◽  
Vittorio Ganfi
Keyword(s):  
Functional Relation ◽  
Prepositional Phrase ◽  
Quantitative Approach ◽  
Romance Languages ◽  
Middle French ◽  
Old Spanish ◽  
Qualitative And Quantitative ◽  
Multiword Expressions ◽  
Diachronic Analysis ◽  
The Relationship

Abstract Lexicological and lexicographical studies on multiword expressions in Romance languages have significantly increased in recent years. Even though some attention has been paid to Multiwords functioning as adjectives and adverbs, the structural and the functional relation between them has not been clarified yet. Employing both a qualitative and quantitative approach, this corpus-based investigation aims at exploring the diatopic distribution and the evolution of Romance multiword lexemes having the form of a prepositional phrase and the function of an adjective or/and an adverb (or both functions). According to data taken from corpora of Latin, Old Italian, Old Spanish and Middle French, this contribution investigates the relationship between the different degrees of schematicity and the productivity of this kind of multiword lexemes in order to highlight the evolutional path and the diachronic/diatopic principles engaged in the multiword modifying system across the different Romance languages taken into consideration.

Design of the Pressurized Tepula Channel

2015 ◽  
Vol 797 ◽  
pp. 219-224
Author(s):  
Ahmed Amine Lamri
Keyword(s):  
Friction Coefficient ◽  
Water Supply ◽  
Turbulent Flow ◽  
Linear Dimension ◽  
Linear Dimensions ◽  
Sanitary Sewers

In order to calculate the linear dimension of a Tepula channel which is frequently used as water supply lines, irrigation, sanitary sewers we adopt a referential model arbitrarily chosen that gives value to the friction coefficient of 1/16. We base on the fundamental formulas of uniform turbulent flow Darcy-Weisbach, Colebrook-white. We find explicit and direct formulas for the calculation of linear dimensions of the channel.

scholarly journals Identification of the Flow Properties of a 0.54% Carbon Steel during Continuous Cooling

Metals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 104
Author(s):  
Christoph Rößler ◽  
David Schmicker ◽  
Oleksii Sherepenko ◽  
Thorsten Halle ◽  
Markus Körner ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Flow Properties ◽  
Carreau Fluid ◽  
Cooling Process ◽  
Material Parameters ◽  
Essential Step ◽  
Deformation Processes ◽  
Structural Carbon ◽  
Experimental Effort ◽  
Structural Carbon Steel

The determinination of material properties is an essential step in the simulation of manufacturing processes. For hot deformation processes, consistently assessed Carreau fluid constitutive model derived in prior works by Schmicker et al. might be used, in which the flow stress is described as a function of the current temperature and the current strain rate. The following paper aims to extend the prior mentioned model by making a distinction, whether the material is being heated or cooled, enhancing the model capabilities to predict deformations within the cooling process. The experimental identifaction of the material parameters is demonstrated for a structural carbon steel with 0.54% carbon content. An approach to derive the flow properties during cooling from the same samples used at heating is presented, which massively reduces the experimental effort in future applications.

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