240 likes | 452 Views
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.
E N D
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 http://sunnyfortuna.com/explore/sights.htm
I-35 bridge failure Multiple deficiencies at inspections www.greentechforum.net
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.”
OPTICAL polycrystal: low porosity polycrystal: high porosity single crystal • 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.)
Structure, Processing, & Properties (d) 30mm (c) (b) (a) 4mm 30mm 30mm • Properties depend on structure ex: hardness vs structure of steel 6 00 5 00 Data obtained from Figs. 10.30(a) and 10.32 with 4 wt% C composition, and from Fig. 11.14 and associated discussion, Callister 7e. Micrographs adapted from (a) Fig. 10.19; (b) Fig. 9.30;(c) Fig. 10.33; and (d) Fig. 10.21, Callister 7e. 4 00 Hardness (BHN) 3 00 2 00 100 0.01 0.1 1 10 100 1000 Cooling Rate (ºC/s) • Processing can change structure ex: structure vs cooling rate of steel
Example 4: Polarized Light www.exploratorium.edu
Classifactions of Materials • Metals - • Ceramics – • Polymers - • Composites - • Semiconductors - • Biomaterials - We will be primarily concerned with Metals, Polymers, and composites
f03_01_pg6 f03_01_pg6
f04_01_pg6 f04_01_pg6
f05_01_pg7 f05_01_pg7
f06_01_pg7 f06_01_pg7
f07_01_pg8 f07_01_pg8
SUMMARY Course Goals: • Use the right material for the job. • Understand the relation between properties, structure, and processing. • Recognize new design opportunities offered by materials selection. • Understand that new materials can be tailored to specific design requirements.