Alf de Ruvo Scholarship for Amanda Mattsson

Tue 05 Feb 2019 10:27

Amanda Mattsson has been awarded the Alf de Ruvo scholarship of 500 000 SEK for her work on Characterisation of time-dependent, statistical failure of cellulose fibre networks at Mid Sweden University’s research centre FSCN. Congratulations Amanda!

amanda mattsson alf de ruvo

The official motivation for the Alf de Ruvo Scholarship

Framställning av olika pappersförpackningar från skogen har länge spelat en huvudroll i svensk ekonomi. Dr Amanda Mattsson tilldelas Alf de Ruvo-stipendiet för utvecklingen av nya principer för materialdesign av cellulosafiberbaserade lättviktskompositer. För wellpappförpackningar är krypegenskaperna av fundamental betydelse i kartongen, men de är också svåra att mäta och kvantifiera. Den praktiska nyttan är att man kan använda metoden för att utveckla resurssnåla och miljöanpassade förpackningar. Baserat på tidsberoende statistisk brott-teori har Amanda Mattsson utvecklat en metod för materialdesign och introducerat ett nytt teoretiskt fundament för tidsberoende statistiska brott för pappersförpackningar. Genom Monte-carlosimuleringar har Amanda Mattsson upptäckt en ny skalningslag för tidsberoende statistiska brott. 

The Scholarship was presented in Ekmandagarna in Stockholm 29-30 January 2019. 

Alf de Ruvo Memorial Foundation

Alf de ruvo Memorial Foundation was established in 2000. Holders of the Alf de Ruvo Scholarship are Birgitta Engberg, Magnus Norgren, Stefan Lindström, Christina Dahlström and Britta Andres from Mid Sweden University.

Amandas research

Cellulosic materials have special advantages for transport packaging, because of their light-weight and recyclable natures and also relatively high specific strength. The strength of such materials is normally evaluated by applying monotonically increasing, quasi-static displacement (or load). However, in real circumstances, the material is subjected to far more complex loading histories, such as creep, fatigue, and random loading. Failures under such circumstances are, not only time-dependent, but also notoriously variable. For example, the coefficient of variation for creep lifetime reaches or even exceeds 100%. The objective of this study is to develop a method to characterise both time-dependent and statistical natures of failures of cellulosic materials. We have used a general formulation of time-dependent, statistical failure, originally proposed by Coleman (J Appl Phys 29(6):968–983, 1958). We have identified three material parameters: (1) characteristic strength, representing short term strength, (2) brittleness parameter (or durability), and (3) Weibull shape parameter related to long-term reliability. These parameters were determined by special protocols of creep and constant loading-rate (CLR) tests for a series of containerboards. Results have shown that these two test methods yield comparable values for the materials parameters. This implies the possibility of replacing extremely time-consuming creep tests with the more time-efficient CLR tests. Comparing the cellulose fibre networks with fibres and composites used for advanced structural applications, we have found that they are very competitive in both reliability and durability aspects with Kevlar and glass-fibre composites.


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The page was updated 1/29/2021