Assessment of metals fabricability by pressure

A variant of quantitative assessment of metals fabricability by pressure is offered according to the standard tests on mechanical properties. The complex parameter is used, defined as geometrical mean of three parameters characterizing plasticity, hardening and energy intensity of alloys deformation. Relations of scientific and engineering characteristics of deformability assessment for the use of scientific researches results in factory practice are determined, being guided on the standard test methods. Examples of the use of received equations are resulted for a number of steels in processes of metal forming. Testing of the proposed method was carried out according to the known data. Estimation of the complex parameters was made in accordance with Harrington desirability scale. The offered technique can be used for an assessment of fabricability of new steels and alloys.

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A Detailed Proposal for an Oxidation Test for Flexible Graphite

Volume 2: Computer Technology and Bolted Joints ◽

10.1115/pvp2017-65887 ◽

2017 ◽

Author(s):

Stephen Bond

Keyword(s):

Test Methods ◽

Standard Test ◽

Ash Content ◽

Factors Affecting ◽

Oxidation Rates ◽

Oxidation Performance ◽

Flexible Graphite ◽

Vast Range ◽

Standard Tests ◽

Modern Standard

While the oxidation of graphite in gaskets is a well known phenomenon it is often poorly quantified and the factors affecting it not always well known. There are some standard tests that can be used to determine graphite quality. While many of these material standards concentrate on the compositional impurities (sulfur, chlorides etc.) and the ash content; these are indicative of other properties and they are no real indication of oxidation performance. Recently, some test methods have been published that suggest a method for measuring oxidation performance; however, they have some shortcomings or constraints. Using modern, standard TGA (ThermoGravimetric Analysis), the work presented in this paper aims to provide a more detailed standard test that can be used to measure the oxidation rate of graphite in flowing air for a given set of time and temperature conditions. The paper will show what other conditions are critical and which are less significant in specifying a standard test. This will lead to the presentation of a suggestion for an improved standard test that builds on and further codifies the tests currently published. Finally, this paper will show the oxidation rates of a variety of different commercial graphite grades to illustrate the vast range of oxidation rates that are possible from the various grades of graphite.

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Mechanically Superior Molybdenum Rhenium (MoRe®) Alloy provides an advanced option for Foot and Ankle Implants

Foot & Ankle Orthopaedics ◽

10.1177/2473011418s00376 ◽

2018 ◽

Vol 3 (3) ◽

pp. 2473011418S0037 ◽

Cited By ~ 1

Author(s):

Selene Parekh ◽

Samuel Adams ◽

James Nunley ◽

Mark Easley ◽

David Pedowitz ◽

...

Keyword(s):

Mechanical Properties ◽

Surgical Techniques ◽

Biomechanical Properties ◽

Delayed Union ◽

Test Methods ◽

Standard Test ◽

Great Promise ◽

Foot And Ankle ◽

Repetitive Stress ◽

Design Options

Category: Other Introduction/Purpose: One of the most common complications in orthopaedic surgery of the foot and ankle is nonunion or delayed union and bone or implant fractures. Although foot and ankle surgery has improved dramatically over the past decades primarily due to the development of better techniques, little progress has been made in the development of new materials for implants. Titanium, the most commonly used alloy for foot and ankle implants, has limited strength and is notch-sensitive so repetitive stress leads to fatigue failure of implants and limits design options. Better materials with optimized biomechanical properties could result in the development of superior foot and ankle implants and surgical techniques. The mechanical properties of Molybdenum-Rhenium (MoRe®), a promising new alloy for foot and ankle implants were tested. Methods: Standard test methods (ASTM 1717) were performed to evaluate the mechanical properties of Molybdenum Rhenium (MoRe®) alloy compared to Titanium (Ti-6Al-4 V, ASTM F136-13 annealed bar, Ti-ELI). Results: MoRe® is composed purely (99.99%) of molybdenum and rhenium and does not contain Nickel. Molybdenum is found in food and is a cofactor to the enzymes xanthine oxidase and sulfite oxidase, which are essential to bone and connective tissue metabolism. Rhenium is an inert metal with no biological affect. Mechanical testing showed MoRe to be superior to Titanium: Yield Strength: MoRe® 280ksi, Titanium 115ksi, Ultimate Tensile Strength: MoRe® 300ksi, Titanium 125 ksi. Elongation and Reduction in Area: MoRe® 13%, 50%, respectively; Titanium 10%, 25%. Recoil: MoRe® <2%, Titanium 6%. Hardness Range: MoRe® 280-800HV, Titanium 350-400HV. Max Run-Out Load Bent Rod: MoRe® 4.0 mm rod 350 N, Titanium 5.5 mm rod 150 N. Decrease in Max Run-Out Load Bent, Unbent, Re-bent Rod: MoRe® -9%, Titanium -17%. Conclusion: The MoRe® alloy, with its advantageous mechanical properties, offers great promise for the design of a new generation of smaller, stronger and more fatigue resistant foot and ankle implants, resulting in less soft tissue disruption, quicker recovery and better outcomes for patients.

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Smart Expandable Cement Additive to Achieve Better Wellbore Integrity

Journal of Energy Resources Technology ◽

10.1115/1.4036963 ◽

2017 ◽

Vol 139 (6) ◽

Cited By ~ 8

Author(s):

A. Dahi Taleghani ◽

G. Li ◽

M. Moayeri

Keyword(s):

Mechanical Properties ◽

Oil And Gas ◽

Setting Time ◽

Oil And Gas Industry ◽

Test Methods ◽

Standard Test ◽

Cement Slurry ◽

Gas Industry ◽

Additive Particles ◽

Cement Additive

One of the serious challenges encountered in cementing oil and gas wells is the failure of the cement sheaths and its debonding from casing or formation rock. Shrinkage of the cement during setting is identified as one of the driving factors behind these issues. Some expansive cement systems have been developed in the oil and gas industry to compensate for the shrinkage effect. All the expansive additives which have been developed so far have chemical reactions with the cement itself that would significantly impact the mechanical strength of the cement. In this paper, we present a new class of polymer-based expandable cement additive particles which are made of shape memory polymers (SMP). This class of polymers is designed to expand to the required extent when exposed to temperatures above 50–100 °C (122–212 °F) which is below the temperature of the cementing zone. It is notable that expansion occurs after placement of the cement but before its setting. The API RP 10 B-2 and 5 have been followed as standard test methods to evaluate expansion and strength of the cement slurry after utilizing the new additive. The proposed additive does not react with the water or cement content of the slurry. Mechanical evaluation tests confirm the potential benefit of this additive without any deteriorative effect on mechanical properties or setting time of the cement paste and significant impact on its mechanical properties. Hence, this additive would provide a reliable way to prevent cement channeling, debonding, and fluid migration to upper formations.

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The Validity of Standard Test Methods for Characterizing Weld Fracture

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2919946 ◽

1992 ◽

Vol 114 (1) ◽

pp. 16-21 ◽

Cited By ~ 1

Author(s):

S. M. Graham ◽

W. G. Reuter ◽

W. R. Lloyd ◽

J. S. Epstein

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Linear Elasticity ◽

Test Methods ◽

Standard Test ◽

Heterogeneous Structure ◽

Displacement Fields ◽

Standard Methods ◽

Fracture Parameters ◽

Homogeneous Materials

Standard methods for testing fracture toughness of homogeneous materials are currently being applied to welds. A weld is, by nature, a heterogeneous structure containing zones with different microstructures and mechanical properties. The validity of using fracture parameters developed for homogeneous materials to characterize fracture of welds has not been established. Tests were conducted to investigate whether the extension of a crack along an interface is governed by the same fracture parameters used to predict fracture in homogeneous materials. The tests involved measuring the displacement fields around a crack tip in the interface between two materials with matched elastic properties and differing yield strengths. The form of the displacement distribution was then compared with the theoretical displacements for linear elasticity and nonlinear elasticity with power-law hardening.

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Influence of Ultrafine Particles on Structure, Mechanical Properties, and Strengthening of Ductile Cast Iron

Metals ◽

10.3390/met8070559 ◽

2018 ◽

Vol 8 (7) ◽

pp. 559 ◽

Cited By ~ 1

Author(s):

Anna Zykova ◽

Dmitry Lychagin ◽

Andrey Chumaevsky ◽

Natalya Popova ◽

Irina Kurzina

Keyword(s):

Mechanical Properties ◽

Cast Iron ◽

Integrated Assessment ◽

Ultrafine Particles ◽

Quantitative Assessment ◽

Structural Phase ◽

Ductile Cast Iron ◽

Physical Mechanisms ◽

Transmission Electron ◽

Made In

Integrated assessment of the influence of an ultrafine mixture TiO2 + ZrO2 + Na3AlF6 on the formation of the structure, mechanical properties, and strengthening of ductile cast iron was made in the paper. The structural-phase composition of ductile cast iron was studied by means of scanning electron microscopy and a transmission electron microscope. Plastic deformation was determined during testing of uniaxial compression. The change in the structural state of the alloy and in its mechanical properties was observed. Quantitative assessment of contributions of separate physical mechanisms to strengthening characteristics of unmodified and modified ductile cast iron was made.

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Studying the influence of the preparation of a new copolyamide as adhesive for wood-wood surfaces

journal of the college of basic education ◽

10.35950/cbej.v17i72.4503 ◽

2019 ◽

Vol 17 (72) ◽

pp. 109-116

Author(s):

Mohammad N. AL-Baiati

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Impact Strength ◽

Wood Adhesive ◽

Test Methods ◽

Standard Test ◽

The Other ◽

Adhesion Properties ◽

Wood Surfaces ◽

Standard Tests

In this research, a new copolyamid was prepared from reaction Aceglutamide with Formaldehyde by esterfication process, and used this copolymer as adhesive between wood – wood surface. Five different weight ( 0.2, 0.4 , 0.6, 0.8 & 1.0 gm ) from the prepared copolymer respectively, were used as adhesive to prepared the specimens of wood / adhesive . Four standard test methods were used to measured the adhesion properties which are; ASTM: D-790, ASTM: D- 695, ISO – 179 & ASTM: D-638 . The results obtained from these tests indicated that, the specimens of wood / adhesive containing 1.0 gm from the prepared copolymer have high values in all standard tests; Impact strength was 45 MPa, Compressive strength was 40 MPa, Flexural strength was 250 MPa and Tensile strength was 8150.41 MPa ; compared with the other specimens which contain on less weight from the prepared copolymer.

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Physical and Mechanical Properties of Tenun Pahang Fabrics using Alternative Yarns

Scientific Research Journal ◽

10.24191/srj.v13i2.9377 ◽

2016 ◽

Vol 13 (2) ◽

pp. 67

Author(s):

Engku Liyana Zafirah Engku Mohd Suhaimi ◽

Jamil Salleh ◽

Suzaini Abd Ghani ◽

Mohamad Faizul Yahya ◽

Mohd Rozi Ahmad

Keyword(s):

Mechanical Properties ◽

Physical And Mechanical Properties ◽

The Other ◽

Silk Fabrics ◽

Recovery Angle ◽

Made In

An investigation on the properties of Tenun Pahang fabric performances using alternative yarns was conducted. The studies were made in order to evaluate whether the Tenun Pahang fabric could be produced economically and at the same time maintain the fabric quality. Traditional Tenun Pahang fabric uses silk for both warp and weft. For this project, two alternative yarns were used which were bamboo and modal, which were a little lower in cost compared to silk. These yarns were woven with two variations, one with the yarns as weft only while maintaining the silk warp and the other with both warp and weft using the alternative yarns. Four (4) physical testings and three (3) mechanical testings conducted on the fabric samples. The fabric samples were evaluated including weight, thickness, thread density, crease recovery angle, stiffness and drapability. The results show that modal/silk and bamboo silk fabrics are comparable in terms of stiffness and drapability, hence they have the potential to replace 100% silk Tenun Pahang.

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