Fibernätverks och materials mekanik

Why should I take this course?
Material is an essential component of the design. Working as an engineer, you will deal with various types of materials. There is a wide class of materials where a fiber network is the main load-carrying component. This class encompasses paper, paperboard, tissue and many biopolymers. These materials are known to have outstanding stiffness-to-mass ratio which is one of the reasons they are so abandon in nature (bones, living tissues, cells, etc.). We will study this class of materials by considering paper and its applications. Despite being simple in use, paper constitutes one of the most complex materials among those you encounter in your daily life. Paper can be easily tested mechanically and exhibits a whole range of behavior during converting and end-use. Therefore, using paper as a core material in this course is an excellent opportunity to train your skills in analyzing various aspects of the mechanical behavior of fiber network materials.

Paper and paperboard are composite materials, which are produced by a continuous process at unprecedented speeds of up to 100 km/h by a complex but yet extremely cost-efficient process. Paper is heterogeneous and anisotropic. In a number of applications, it is used beyond its elastic limit. The strength of paper is size-dependent and is different in tension and compression. Furthermore, paper absorbs water, which changes its mechanical properties and dimensions.

In this course, you will be exposed to the intricate mechanics of paper through a number of case studies, in which we will investigate real problem and learn how to solve them. Other fiber network materials made of various types of fibers will also be covered in the course.

At KTH, we have world-leading expertise in paper mechanics, and we contributed to the textbook that will be used in the course. We will also use the expertise available at Rise Bioeconomy, a recognized research institute dealing with bio-based materials such as paper and paperboard.

Learning objectives:

After the course, the students should be able to

• discuss the application areas, advantage and disadvantages of fiber network materials, in particular paper and board
• describe and analyze important paper technology applications using correct solid mechanics terminology,
• relate the results from the most important methods for mechanical testing of paper and board to the appropriate solid mechanics terminology,
• describe important aspects of the constitutive modelling of paper and board for analyses of converting and end-use applications,
• demonstrate the benefits of mathematical modelling and numerical analyses in packaging applications,
• discuss and argue for experimental and numerical results orally and in writing, and
• appreciate the advantages, disadvantages and limitations of using paper and board as a renewable material. 
• be able to compare various materials for packaging applications using material databases from both strength and environmental perspectives.