Assessement of tensile strength of graphites by the Iosipescu coupon test
Main Author: | |
---|---|
Publication Date: | 2007 |
Other Authors: | , |
Format: | Article |
Language: | eng |
Source: | Materials research (São Carlos. Online) |
Download full: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000300003 |
Summary: | Polycrystalline graphites are widely used in the metallurgical, nuclear and aerospace industries. Graphites are particulated composites manufactured with a mixture of coke with pitch, and changes in relative proportions of these materials cause modifications in their mechanical properties. Uniaxial tension tests must be avoided for mechanical characterization in this kind of brittle material, due to difficulties in making the relatively long specimens and premature damages caused during testing set-up. On other types of tests, e.g. bending tests, the specimens are submitted to combined stress states (normal and transverse shear stresses). The Iosipescu shear test, is performed in a beam with two 90° opposite notches machined at the mid-length of the specimens, by applying two forces couples, so that a pure and uniform shear stress state is generated at the cross section between the two notches. When a material is isotropic and brittle, a failure at 45° in relation to the beam long axis can take place, i.e., the tensile normal stress acts parallel to the lateral surface of the notches, controls the failure and the result of the shear test is numerically equivalent to the tensile strength. This work has evaluated a graphite of the type used in rocket nozzles by the Iosipescu test and the resulted stress, ~11 MPa, was found to be equal to the tensile strength. Thus, the tensile strength can be evaluated just by a single and simple experiment, thus avoiding complicated machining of specimen and testing set-up. |
id |
ABMABCABPOL-1_799a6011e1fae912e00ae52313d0a9c4 |
---|---|
oai_identifier_str |
oai:scielo:S1516-14392007000300003 |
network_acronym_str |
ABMABCABPOL-1 |
network_name_str |
Materials research (São Carlos. Online) |
repository_id_str |
|
spelling |
Assessement of tensile strength of graphites by the Iosipescu coupon testpolycrystalline graphitesmechanical propertiestensile strengthshear strengthweibull modulusPolycrystalline graphites are widely used in the metallurgical, nuclear and aerospace industries. Graphites are particulated composites manufactured with a mixture of coke with pitch, and changes in relative proportions of these materials cause modifications in their mechanical properties. Uniaxial tension tests must be avoided for mechanical characterization in this kind of brittle material, due to difficulties in making the relatively long specimens and premature damages caused during testing set-up. On other types of tests, e.g. bending tests, the specimens are submitted to combined stress states (normal and transverse shear stresses). The Iosipescu shear test, is performed in a beam with two 90° opposite notches machined at the mid-length of the specimens, by applying two forces couples, so that a pure and uniform shear stress state is generated at the cross section between the two notches. When a material is isotropic and brittle, a failure at 45° in relation to the beam long axis can take place, i.e., the tensile normal stress acts parallel to the lateral surface of the notches, controls the failure and the result of the shear test is numerically equivalent to the tensile strength. This work has evaluated a graphite of the type used in rocket nozzles by the Iosipescu test and the resulted stress, ~11 MPa, was found to be equal to the tensile strength. Thus, the tensile strength can be evaluated just by a single and simple experiment, thus avoiding complicated machining of specimen and testing set-up.ABM, ABC, ABPol2007-09-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000300003Materials Research v.10 n.3 2007reponame:Materials research (São Carlos. Online)instname:Universidade Federal de São Carlos (UFSCAR)instacron:ABM ABC ABPOL10.1590/S1516-14392007000300003info:eu-repo/semantics/openAccessManhani,Luis Guilherme BorzaniPardini,Luiz ClaudioLevy Neto,Flamínioeng2007-10-17T00:00:00Zoai:scielo:S1516-14392007000300003Revistahttp://www.scielo.br/mrPUBhttps://old.scielo.br/oai/scielo-oai.phpdedz@power.ufscar.br1980-53731516-1439opendoar:2007-10-17T00:00Materials research (São Carlos. Online) - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.none.fl_str_mv |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
title |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
spellingShingle |
Assessement of tensile strength of graphites by the Iosipescu coupon test Manhani,Luis Guilherme Borzani polycrystalline graphites mechanical properties tensile strength shear strength weibull modulus |
title_short |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
title_full |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
title_fullStr |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
title_full_unstemmed |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
title_sort |
Assessement of tensile strength of graphites by the Iosipescu coupon test |
author |
Manhani,Luis Guilherme Borzani |
author_facet |
Manhani,Luis Guilherme Borzani Pardini,Luiz Claudio Levy Neto,Flamínio |
author_role |
author |
author2 |
Pardini,Luiz Claudio Levy Neto,Flamínio |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Manhani,Luis Guilherme Borzani Pardini,Luiz Claudio Levy Neto,Flamínio |
dc.subject.por.fl_str_mv |
polycrystalline graphites mechanical properties tensile strength shear strength weibull modulus |
topic |
polycrystalline graphites mechanical properties tensile strength shear strength weibull modulus |
description |
Polycrystalline graphites are widely used in the metallurgical, nuclear and aerospace industries. Graphites are particulated composites manufactured with a mixture of coke with pitch, and changes in relative proportions of these materials cause modifications in their mechanical properties. Uniaxial tension tests must be avoided for mechanical characterization in this kind of brittle material, due to difficulties in making the relatively long specimens and premature damages caused during testing set-up. On other types of tests, e.g. bending tests, the specimens are submitted to combined stress states (normal and transverse shear stresses). The Iosipescu shear test, is performed in a beam with two 90° opposite notches machined at the mid-length of the specimens, by applying two forces couples, so that a pure and uniform shear stress state is generated at the cross section between the two notches. When a material is isotropic and brittle, a failure at 45° in relation to the beam long axis can take place, i.e., the tensile normal stress acts parallel to the lateral surface of the notches, controls the failure and the result of the shear test is numerically equivalent to the tensile strength. This work has evaluated a graphite of the type used in rocket nozzles by the Iosipescu test and the resulted stress, ~11 MPa, was found to be equal to the tensile strength. Thus, the tensile strength can be evaluated just by a single and simple experiment, thus avoiding complicated machining of specimen and testing set-up. |
publishDate |
2007 |
dc.date.none.fl_str_mv |
2007-09-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000300003 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000300003 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S1516-14392007000300003 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
ABM, ABC, ABPol |
publisher.none.fl_str_mv |
ABM, ABC, ABPol |
dc.source.none.fl_str_mv |
Materials Research v.10 n.3 2007 reponame:Materials research (São Carlos. Online) instname:Universidade Federal de São Carlos (UFSCAR) instacron:ABM ABC ABPOL |
instname_str |
Universidade Federal de São Carlos (UFSCAR) |
instacron_str |
ABM ABC ABPOL |
institution |
ABM ABC ABPOL |
reponame_str |
Materials research (São Carlos. Online) |
collection |
Materials research (São Carlos. Online) |
repository.name.fl_str_mv |
Materials research (São Carlos. Online) - Universidade Federal de São Carlos (UFSCAR) |
repository.mail.fl_str_mv |
dedz@power.ufscar.br |
_version_ |
1754212658554339328 |