Effect of vacuum and Focused Ion Beam generated heat on fracture properties of hydrated cement paste

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F19%3A00333744" target="_blank" >RIV/68407700:21110/19:00333744 - isvavai.cz</a>

Alternative codes found

RIV/68378271:_____/19:00540578

Result on the web

<a href="https://doi.org/10.1016/j.cemconcomp.2019.03.027" target="_blank" >https://doi.org/10.1016/j.cemconcomp.2019.03.027</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cemconcomp.2019.03.027" target="_blank" >10.1016/j.cemconcomp.2019.03.027</a>

Result language

angličtina

Original language name

Effect of vacuum and Focused Ion Beam generated heat on fracture properties of hydrated cement paste

Original language description

The paper focuses on quantifying of vacuum and heat influence as unavoidable effects that appear during preparation and in-situ monitoring of micromechanical performance of cement pastes. Experimental tests at micrometer scale employ microscopic techniques of Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB). High vacuum is applied to samples during SEM-FIB procedures causing dessication and densification of primary cement paste constituents, the CSH gels. Collapse of pores and microstructural packing leads to their local stiffening and change in their fracture properties compared to usual partially saturated conditions of atmospheric pressures. The effect of vacuum is quantified for individual paste constituents in terms of their elastic moduli, tensile strengths and fracture energies measured on 15–20 μm long cantilever micro-beams inside SEM chamber. It was found that application of vacuum in SEM increases elastic moduli of inner and outer products by ~30%, tensile strength rises 2.3–2.5 times. The effect of local heating due to ionic interactions during FIB milling is studied by means of micromechanical measurements on micro-beams and finite element (FE) numerical model. It is shown that high energy milling (30 kV, 30 nA) causes substantial microstructural and subsequent mechanical changes leading to further stiffening and tensile strength increase in the micrometer scale. The effect originates from phase changes caused by elevated temperatures under the ion beam that can be locally very high (thousands of K according to the simplified FE model). The paper also reports micromechanical response received by low energy milling for which microstructural changes due to increased temperature are restricted to very small volumes and can be assumed to be negligible with respect to the micro-beam dimensions.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

20101 - Civil engineering

Project

<a href="/en/project/GA17-05360S" target="_blank" >GA17-05360S: Small-scale fracturing of amorphous and crystalline materials assessed with nanoindentation and focused ion beam</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Cement and Concrete Composites

ISSN

0958-9465

e-ISSN

1873-393X

Volume of the periodical

100

Issue of the periodical within the volume

July

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

139-149

UT code for WoS article

000468708900014

EID of the result in the Scopus database

2-s2.0-85064738841