Mechanical properties of polymers, composites-Nielsen 2010 Part 11 ppt

... plastic deformation of solids are often controlled by the movem ent of defects. It is, therefore, important for the student of mechanical behavior to be familiar with the different types of defects that ... Hardness The hardness of a material is a measure of its resistance to penetration by an indenter. Hardness is also a measure of strength and often has the units of stress...

Ngày tải lên: 11/08/2014, 15:20

... Inc. Cottrell, A.H. (1957) The Properties of Materials at High Rates of Strain. Institute of Mechanical Engineering, London, UK. Courtney, T.H. (1990) Mechanical Behavior of Materials, John Wiley, ... structure. Note that since [ " 110 1] direction is common to both the (111 ) and (1 " 111 Þ closed packed planes, the screw dislocation can glide on either of these p...

Ngày tải lên: 11/08/2014, 15:20

... intersection of a 2 h " 11 " 111 idislocationsglidingon{101}slip planes.Thisresultsinthefollowingdislocationreaction(Fig.13.7): a 2 h " 11 " 111 i ð101Þ þ 1 2 h111i ð " 110 1Þ !a½001ð12:3Þ Sincetheresultinga[001]dislocationissessile,thisprovidesthefirststageof cracknucleationthatoccursduetotherelativemotionofmaterialabove andbelow ... Inc. Rousselier(1987),Fo...

Ngày tải lên: 11/08/2014, 15:20

... theoreti- cally the effect of branching on viscosity. The important factor is the ratio of the mean-square radius of the branched molecules to that of the linear polymer of the same molecular weight, ... long-time tail of the stress relaxation curve or the onset of the flow regime]. The Doi-Edwards roptation model thus predicts that the width of the modulus plateau varies as t...

Ngày tải lên: 12/08/2014, 03:20

... the required particle spacing of incoherent particles! b) Calculate the particle radius, assuming a copper content of 4 vol-%! To simplify the calculation, neglect the solubility of copper in ... with a degree of polymerisation of 10 4 . a) Calculate the molar mass of the molecule! The molar mass of carbon is 12.01 g/mol, that of hydrogen is 1.01 g/mol. b) Calculate the length...

Ngày tải lên: 11/08/2014, 15:20

... t h e mechanical properties of polymers very complex if it were not for some general phenomena and principles that underlie all of these various properties and determine t h e outcome of various ... Dynamical Mechanical Properties I- Introduction and Instruments H. Temperature and Frequency Effects Library of Congress Cataloging-In-Publitation Date Nielsen. Lawrence E. Mec...

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... Transitions 11 cycle as given by Some of the interrelationships between the complex quantities are Mechanical Tests and Polymer Transitions 3 II. MECHANICAL TESTS There are a bewildering number of mechanical ... types of apparatus arc capable of covering the range from a small . fraction of a cycle per second up to millions of cycles per second. Most instruments measu...

Ngày tải lên: 12/08/2014, 03:20

... Behavior of High Polymers. Intersaence, New York. 1948. 3. J I), Ferry. Viscoelastic properties of Polymers, 3rd ed., Wiley. New York, 1980. 4. I , n, Nielsen. Mechanical Properties of Polymers. ... kg/cm 2 . 4. A load of 100 Ib is applied to a specimen that has a length of 4 in. between grips, a width of 1 in ., and a thickness of 0.10 in. If the Young's mod...

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... The mechanical properties of compatible blends resemble those of random copolymers, having a single T^ value and modulus tran- sition zone. T K varies rather regularly with composition, often ... effect of any change in £ ()jr Copolymers and plasticized materials often show another effect—a broadening of the transition region with a decrease in the slope of the modulus curve in...

Ngày tải lên: 12/08/2014, 03:20

... constants of the model. The values of the constants are given in Table I. Curve I is the same as shown in Figure 4, curve II shows onlv a small amount of viscous creep, and in curve 111 , viscous ... creep of rigid materials, the difficulty arises from the ne- cessity to measure accurately very small deformations and deformation rates. In the case of the stress relaxation of rigi...

Ngày tải lên: 12/08/2014, 03:20