Stress_Corrosion_Presentation_EMA_6715

Stress_Corrosion_Presentation_EMA_6715 - Mechanical...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Mechanical Properties of Glass Elastic Modulus and Microhardness [Chapter 8 – The “Good Book”*] Strength and Toughness [Chapter 18] Fracture mechanics tests Fractography Stress Corrosion Fracture Statistics *A. Varshneya, “Fundamentals of Inorganic Glasses”, Society of Glass Technology (2006) [email protected] 1 Virtual Course on Glass - The Properties of Glass: Mechanical Properties of Glass - Lecture 13
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Early investigators observed the time dependence of the strength of glass [email protected] Virtual Course on Glass - The Properties of Glass: Mechanical Properties of Glass - Lecture 13 2 Stress-time characteristics of glass, from bending tests on 1/4 inch diameter soda-lime-silicate rods E.B. Shand, “Experimental Study of Fracture of Glass: I, The Fracture Process,” J. Am. Ceram. Soc. 37 , 52 (1954); original figure from C.J. Phillips, “Mechanical Strength of Glass”;report, Research Laboratory, Corning Glass Works, 1937.
Background image of page 2
Early History Grenet (1899) – First experiments to show that glass failed after time under load. Early studies 1920’s +(up to the development of fracture mechanics) (Preston, Milligan, Holland and Turner, Mould and Southwick, etc., etc.) depended on measurements of strength, and were therefore unable to separate effects of flaw severity from flaw extension.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Progress Orowan (1944) - Recognized that the fracture energy of glass should be dependent on the environment in which it was measured. Gurney (1947) – Proposed that the strain at a crack tip made the material more chemically active. Gibbs and Cutler (1951); Stuart and Anderson (1953) – Use of chemical rate theory to explain environmentally enhanced crack growth.
Background image of page 4
concepts to explain moisture enhanced crack growth [email protected] Virtual Course on Glass - The Properties of Glass: Mechanical Properties of Glass - Lecture 13 5 "Due to concentration of strain energy, the material at the end of the crack has a much higher free energy than normal unstressed glass, and is therefore much more chemically active. Atmospheric attack will result in the formation of a complex of glass and atmospheric constituents. The crack will extend continually if the strength of this complex, during or after its formation, is less than the load imposed on it." C. Gurney and S. Pearson, “The Effect of the Surrounding Atmosphere on the Delayed Fracture of Glass,” Proc. Phys. Soc B
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 28

Stress_Corrosion_Presentation_EMA_6715 - Mechanical...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online