Materials Science Lecture 1

What is Materials Science ? Why do we study it ?

Example 1:Protective tiles on the space shuttle. What conditions / environments might those tiles see? What is the major concern in the design of those tiles?

Example 2: A concrete bridge What is the role of the bridge? Fern Bridge, California

I-35 bridge failure Multiple deficiencies at inspections

Tacoma Narrows

Materials History: Prehistoric The earliest materials? Two cave people…

Materials History: Ancient History Extraction of Metals Processing Natural materials What’s next?

Materials Science and Engieering We study materials to learn why they behave the way they do so that we may use that knowledge to make good engineering decisions in choosing the right materials for the job and so that we may, if necessary, seek out methods of creating materials that will serve our needs best.”

Transmittance: --Aluminum oxide may be transparent, translucent, or opaque depending on the material structure. Adapted from Fig. 1.2, Callister 7e. (Specimen preparation, P.A. Lessing; photo by S. Tanner.) single crystal polycrystal: low porosity polycrystal: high porosity OPTICAL

Example 3: Follow the Bouncing Ball

ex: hardness vs structure of steel Properties depend on structure Data obtained from Figs (a) and with 4 wt% C composition, and from Fig and associated discussion, Callister 7e. Micrographs adapted from (a) Fig ; (b) Fig. 9.30;(c) Fig ; and (d) Fig , Callister 7e. ex: structure vs cooling rate of steel Processing can change structure Structure, Processing, & Properties Hardness (BHN) Cooling Rate (ºC/s) (d) 30  m (c) 4 m4 m (b) 30  m (a) 30  m

Example 4: Polarized Light

Four Components to the Discipline of MSE

Classifactions of Materials oMetals - oCeramics – oPolymers - oComposites - oSemiconductors - oBiomaterials - We will be primarily concerned with Metals, Polymers, and composites

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Use the right material for the job. Understand the relation between properties, structure, and processing. Recognize new design opportunities offered by materials selection. Course Goals: SUMMARY Understand that new materials can be tailored to specific design requirements.