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Students Work Guide

Every team/student is searching for information that is somehow linked to the other teams/students’ topics.

Organization systems: analyze the material classification approaches in Architecture, Engineering, Material Science, Design fields (Interior design, Landscape design, Fashion-Textile). You will try to uncover the point of view of these approaches: they could be more descriptive, more on a particular application, or on the understanding of the basic internal structure of materials. For example: the Engineering System focuses on the performances of materials and structures.

You should differentiate between traditional and alternative classification systems.

Internal general structure of materials: particularly involved with the arrangement of atoms and molecules held together with different types of chemical bonding forces. They will work with solid materials and they will concentrate in their intrinsic properties and composition (crystalline solids, polycrystalline solids, amorphous solids). The structure of material influences the final characteristics and properties of the material, at the micro and macro levels. They will analyze the arrangements of the structures components and their orders.

Intrinsic properties: are determinate by the molecular structure (= chemical composition) of the material. You could try to define the strength and the hardness of a material related to forces, and also to the substance’s melting and boiling points. Strength is an intrinsic property. Mechanical properties are intrinsic (elastic, toughness) as well as physical properties (conductivity, heat, density) and chemical properties (reactivity, valence, solubility).

Extrinsic properties: are defined by the macrostructure of the material, not just by the composition alone. Optical and many acoustical properties are considered extrinsic. Optical properties are: reflectivity, transmissivity, absorptivity.

Most materials undergo property changes with an input of energy. The changes are direct and reversible in one or more of their properties.

After a definition of intrinsic and extrinsic properties, you should concentrate on the 5 categories of material properties: mechanical, thermal, electrical, chemical, optical. They indicate the energy stimuli that every material must respond to. For ex.: Mechanical properties determine how a material will behave when subjected to a load (weight, force, impact, torsion). The behavior that results from these loads includes strain, deformation, or fracture. Mechanical properties: they depend on what (factors)? Those factors are influenced by what (material type and composition)? Now, for each of the 5 properties you should give us material examples. Metals have thermal properties (thermal conductivity). If you talk about wood, you should associate a category of properties to it, etc...

Characteristics of traditional materials and high performance materials according to their behavior: they have a fixed response to external stimuli. What does it mean? What happen to their properties under normal conditions? Following the proposed classification, you must search for primary and derivate materials. You will find, besides more traditional polymers (plastics, rubber, etc.), materials like temperature-responsive polymers and shape memory polymers that are classified as smart materials. Important is the understanding of properties, behaviors and responses to stimuli. SM sense and react to stimuli and environmental conditions. Most everyday materials have physical properties, which cannot be significantly altered.

Nanomaterials and Nanotechnology : technologies associated with materials and processes at the nanometer scale, 10-9m. The combination of smart material and nanotechnology provides many advantages, realizes novel designs that could not be achieved in traditional engineering and offers greater opportunities as well as challenges. The field of Smart Materials and Nanotechnology is very diverse with application ranging from bioengineering to photonics. Nanotechnology is rapidly developed and it permits control of matter at the level of atoms and molecules which would form the building blocks of smart materials. Smart materials are thus evolving from traditional fiber reinforced composite through functionally graded materials to the current nanotechnologically grown materials. These materials will thus have the capability of closely mimicking (biomimetics) nature enabling structures to act like human skin, or a leaf's chlorophyll. The development of true smart materials at the atomic scale is still some way off, although the enabling technologies are under development (from ‘smart-nano.org’). Nanotechnology will be able to program material properties and to build materials from scratch. It would be interesting to explore speculative potential applications.

Due Sept. 14, 2010

Phase 01: Definition and Classification

Reference - Reading Tip:

Michelle Addington, Daniel Schodek: Smart Materials and Technologies, Architectural Press, 2005

In this book materials and technologies are categorized by behavior- physical and phenomenological- and overlaid with increasing component and system complexity.

Smart Materials characteristics:

SM – Type 1: Property changing-Intrinsic response variation of material to specific internal or external stimuli (Thermochromic, Magnetorheological, Thermotropic, Shape memory):

SM – Type 2: Energy exchanging- responses can be computationally controlled or enhanced (Photovoltaic, Thermoelectric, Piezoelectric, Photoluminescent, Electrostrictive)

A smart material has an inherent “active” behavior that makes it to fit into several categories. For example: electrochromic glass is simultaneously a glazing material, a window, a curtain wall system, a lighting control system or an automated shading system. It has a lot to do with new technologies.

It is necessary a multi-layered classification of SM according to its physical behavior (what it does) and the phenomenological behavior (the results, the effects, the actions, what do we want the material to do?, the architect’s intention). The SM produce direct effects on the energy environments (luminous, thermal, and acoustic), or indirect effects on systems (energy generation, mechanical equipment).

Phase 01: Definition and Classification

Assignment 1.1

Topic 1- Traditional Architectural Classifications:

• USA- Construction Specifications institute (CSI)- Marshall
• Other Classification Systems (Material Science, Engineering)- Marshall
• Material ConneXion
• Technotextiles (see for books on Fashion Design materials)- Ramon

Topic 2 and 3- Traditional Materials characteristics:

TM- Fixed responses to external stimuli (material properties remain constant under normal conditions).

TM may range from:

Topic 2

a) Primary material classes:

• Metals (pure metals, transitional metal);- Will
• Ceramics; -Chris D.
• Polymers; - Jon Pace

Topic 3

b) Derivated classes:

• Composites (High performance strength or stiffness applications. Reinforcing materials, Resin and Matrix materials, Core materials). - Aaron

Properties of materials

Topic 4- Intrinsic properties: internal molecular structure- chemical composition-( for ex. strenght); related to material behavior. Knowledge of atomic and molecular structure (to understand the intrinsic properties) of materials. Bonding forces.- Pedro

Topic 5- Extrinsic properties :macrostructure- (for ex. optical properties).- Jose

Topic 6 - Total of 5 material properties indicative of the energy stimuli that every material must respond to:

• mechanical (Scott),
• electrical (Scott),
• thermal (Jonah A.),
• chemical (Yost),
• optical (Alan).

Topic 7- Nanomaterials (Nanotechnology)- Chris P., Mark