Tavares et al 2021a - Revision history

Materiales.Compuestos at 14:32, 11 December 2022

2022-12-11T14:32:03Z

Materiales.Compuestos at 14:31, 11 December 2022

2022-12-11T14:31:32Z

Scipediacontent at 17:06, 7 May 2022

2022-05-07T17:06:15Z

Show changes

Scipediacontent: Scipediacontent moved page Draft Content 376423882 to Tavares et al 2021a

2022-03-31T19:34:46Z

Scipediacontent moved page Draft Content 376423882 to Tavares et al 2021a

Scipediacontent: Created page with "== Abstract == High performance composites can be designed, and their properties tailored to enhance specific mechanical (or multifunctional) properties of the material. Fibr..."

2022-03-31T19:34:44Z

Created page with "== Abstract == High performance composites can be designed, and their properties tailored to enhance specific mechanical (or multifunctional) properties of the material. Fibr..."

New page

== Abstract ==

High performance composites can be designed, and their properties tailored to enhance specific mechanical (or multifunctional) properties of the material. Fibre hybridization, which consists of combining multiple types of fibres in the same composite material, is a strategy that can lead to improved composite properties and performance, as it not only changes the material properties but also  the damage propagation mechanisms leading to final failure.
In this work, two numerical frameworks are proposed to analyse the mechanics of failure of hybrid polymer composites. Firstly, a FEM framework is used to analyse the mechanisms that lead to longitudinal failure of composite materials. The effects of superimposed hydrostatic pressure on longitudinal tensile failure is analysed and a generalized reduction in strength with increasing pressure is predicted. Secondly, a dynamic Spring Element Model is proposed and used to analyse the dynamics of the formation of clusters of broken fibres and the effects of fibre dispersion in hybrid composites, concluding that higher fibre dispersion leads to improved material performance.
Additionally, an experimental campaign on two different hybrid materials (inter and intratow) is performed to understand the effect of hybridization on fibre dominated properties, namely longitudinal tensile strength and translaminar fracture toughness. The interply hybrid material is obtained by stacking alternating T800 and HR40 thin-ply layers, while the intratow is obtained by combining the two types of fibres in the same layer using spread tow technology. A change in the damage mechanisms through hybridization is observed, which can lead to improved material performance.

== Full document ==
<pdf>Media:Draft_Content_376423882native-articles-510.pdf</pdf>

@@ Line 123: / Line 123: @@
 From the tensile tests in the unidirectional composites, it was concluded that there was a reduction in strength for the hybrid materials when comparing to the T800 baseline. Additionally, Hybrid 2-1 and Hybrid 1-1 materials had a very similar strength as the HR40 material, being their failure dominated by the failure of the HR40 fibres. The Hybrid 4-1 material with a 12% of HR40 fibres showed the highest strength of the hybrid materials. Additionally, a high non-linear behaviour prior to the failure was observed [2]. This non-linearity is associated with the failure of the HR40 fibres, that have a lower failure strain and that, in this hybrid, did not lead to the failure of the material, as the T800 fibres could support the additional load, due to the higher T800 volume fraction.
 From the analysis of the DENT specimens it was concluded that all hybrid materials had a lower fracture toughness than the baseline non-hybrid T800 material. This reduction of fracture toughness was attributed to the addition of the more brittle HR40 fibres without promoting other failure mechanisms with the exception of fibre failure, was seen to be crucial in the increase of the apparent fracture toughness of interply hybrid materials by Danzi [8]. The reduction is fracture toughness was attributed to the low fibre dispersion achieved via the mechanical spreading process used, meaning that the tows of the different fibre types did not successfully combine in the second stage of the process. This was a consequence of the low spreading ratio achieved with the mechanical spreader used. However, higher spreading ratios could not be achieved as it would lead to extensive fibre damage during the manufacturing process and, therefore, a low quality material.
@@ Line 175: / Line 173: @@
 |}
 <div class="center" style="width: auto; margin-left: auto; margin-right: auto;">

@@ Line 1: / Line 1: @@
 ==1 Introduction==
@@ Line 106: / Line 22: @@
 Additionally, the effect of hydrostatic pressure on the tensile failure of fibre reinforced composites is addressed and the generalized strength reduction with increased pressure is shown to be well captured by the models (Figure 2), however, no key differences were observed in the failure mechanisms.
+[[File:Tavares_et_al_2021a-image6.png|centre|600x600px]]
-[[Image:Tavares_et_al_2021a-image6.png|600px]]
 <div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
@@ Line 193: / Line 108: @@
 The results of the open-hole tensile tests performed show a very interesting behaviour of the hybrid materials. Notched tensile tests are not only dominated by strength or toughness, but both properties interact and affect the notched strength of the material. It was concluded that the H2 material had the highest notched strength, higher than the non-hybrid T800 baseline, however, the H1 material showed the lowest strength. Analysing the notch sensitivity of these specimens, it is concluded that the H2 material has a very notch insensitive behaviour, being the normalized strength of the 12 mm wide specimens higher than the theoretical notch insensitive limit [2]. The H1 material, although having lower unnotched and notched strengths than the baseline T800, also shows a high notch intensive behaviour, which can be explained by the complex failure mechanisms that occur in the hybrid materials (Figure 6).
-<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
+<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">[[File:Captura de pantalla 2022-12-11 152511.png|centre|600x600px]]</div>
- [[Image:Tavares_et_al_2021a-image11.png|444px]] </div>
 <div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
@@ Line 214: / Line 128: @@
 <div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
-<span style="text-align: center; font-size: 75%;">'''Table 2. '''Material properties and test results for the manufactured materials.</span></div>
+<span style="text-align: center; font-size: 75%;">'''Table 2. '''Material properties and test results for the manufactured materials</span></div>
 {| style="width: 100%;border-collapse: collapse;"

← Older revision	Revision as of 19:34, 31 March 2022
(No difference)