EBOOK - Kỹ thuật vật liệu 1 (Michael F. Ashby & David R. H. Jones) - 322 Trang.
particular application, but not necessarily (although sometimes) new in the sense of ‘recently developed’. Plastic paper clips and ceramic turbine-blades both represent attempts to do better with polymers and ceramics what had previously been done well with metals. And engineering disasters are frequently caused by the misuse of materials. When the plastic tea-spoon buckles as you stir your tea, and when a fleet of aircraft is grounded because cracks have appeared in the tailplane, it is because the engineer who designed them used the wrong materials or did not understand the properties of those used. So it is vital that the professional engineer should know how to select materials which best fit the demands of the design - economic and aesthetic demands, as well as demands of strength and durability.
1. Engineering Materials and their Properties examples of structures and devices showing how we select the right material for the job
A. Price and availability
2. The Price and Availability of Materials 15
what governs the prices of engineering materials, how long will supplies last, and how can we make the most of the resources that we have?
B. The elastic moduli
3. The Elastic Moduli 27
stress and strain; Hooke’s Law; measuring Young’s modulus; data for design
4. Bonding Between Atoms 36
the types of bonds that hold materials together; why some bonds are stiff and others floppy
5. Packing of Atoms in Solids 45
how atoms are packed in crystals - crystal structures, plane (Miller) indices, direction indices; how atoms are packed in polymers, ceramics and glasses
6. The Physical Basis of Young’s Modulus 58
how the modulus is governed by bond stiffness and atomic packing; the glass transition temperature in rubbers; designing stiff materials - man-made composites
7. Case Studies of Modulus-limited Design 66
the mirror for a big telescope; a stiff beam of minimum weight; a stiff beam of minimum cost.
C. Yield strength, tensile strength, hardness and ductility
8. The Yield Strength, Tensile Strength, Hardness and Ductility definitions, stress-strain curves (true and nominal), testing methods, data
9. Dislocations and Yielding in Crystals
the ideal strength; dislocations (screw and edge) and how they move to give plastic flow
10. Strengthening Methods and Plasticity of Polycrystals solid solution hardening; precipitate and dispersion strengthening; work-hardening; yield in polycrystals
11. Continuum Aspects of Plastic Flow the shear yield strength; plastic instability; the formability of metals and polymers
12. Case Studies in Yield-limited Design
materials for springs; a pressure vessel of minimum weight; a pressure vessel of minimum cost; how metals are rolled into sheet
D. Fast fracture, toughness and fatigue
where the energy comes from for catastrophic crack growth; the condition for fast fracture; data for toughness and fracture toughness 13. Fast Fracture and Toughness
14. Micromechanisms of Fast Fracture ductile tearing, cleavage; composites, alloys - and why structures are more likely to fail in the winter
15. Fatigue Failure
fatigue testing, Basquin’s Law, Coffin-Manson Law; crack growth rates for pre-cracked materials; mechanisms of fatigue.