Conference on composite materials for structural performance: Towards higher limits

This will make it possible to design more innovative, cost-effective and reliable components for wind turbines, ships and aircrafts. The deadline for submitting abstracts to the conference is 15 March 2011.

Today, most wind turbine blades are made of composite materials. Composite materials are based on plastic reinforced with long aligned fibres, which are made of either glass, carbon, kevlar or other strong materials. The fibres are arranged in layers on top of each other and are kept together by the plastic, which is also called a matrix. The strength and durability of the components depend on the properties of the materials and on the design methods and criteria used for designing the components. Similarly, composite materials are used for other large constructions such as ships and aircrafts.

Limits can be expanded

There is a great need in industry for improving the properties of composite materials, e.g. for developing materials equally strong, but considerably lighter in order to save energy and increase cost-effectiveness.

It is possible to expand the limits for the properties of materials by further developing the materials and by providing more insight into how composite materials work on different length scales. How is the interaction e.g. between the properties of the fibres and the interface between the fibres and the matrix in which they are embedded. This is done through experiments and mathematical modelling on microscale.

Design limits e.g. criteria for materials failure and lifetime predictions can be expanded by developing and validating improved models for the critical limit states, e.g. the onset of fatigue failure under multiaxial stress state, the use of damage tolerant design approach and the use of more advanced modelling tools such as cohesive zone modelling.

In order to understand a cohesive law, imagine a child trying to separate a couple of Lego bricks from each other. The child's strength is not enough to do this, so an adult must help. Having more strength, the adult is able to loosen the bricks slightly and give them back to the child who is now able to separate the pieces entirely. Once the bricks have been loosened just a little, only a little force is needed to get them apart.

In other words, a cohesive law is a mathematical description of the force as a function of separation. This description actually applies to anything that can break. Using the cohesive laws in the mathematical models of composite material makes it possible to simulate how a break will develop.

Organisation

The 32nd International Risø Symposium on Materials Science is organised by the Materials Research Division, Risø DTU and the Danish Centre for Composite Structures and Materials for Wind Turbines (DCCSM).

Abstracts can be submitted with 1 page and 1 figure maximum. The author should enclose name, affiliation, postal address, email address and telephone number. Please send abstracts to symposium@risoe.dk

Important dates:

- The deadline for submitting abstracts: 15 March 2011

- The deadline for registering for the conference: 1 July 2011

- Conference dates: 5 - 9 September 2011

Provided by Risoe National Laboratory for Sustainable Energy, the Technical University of Denmark