Fatigue performance

Cord materials such as nylon, polyester, and steel wire conventionally used in tires are twisted and therefore exhibit a nonlinear stress—strain relationship. The cord is twisted to provide reduced bending stiffness and achieve high fatigue performance for cord—mbber composite stmcture. The detrimental effect of cord twist is reduced tensile strength. Analytical studies on the deformation of twisted cords and steel wire cables are available (22,56—59). The tensile modulus E of the twisted cord having diameter D and pitchp is expressed as follows (60) ... 

These values are determined by experiment. It is, however, by no means a trivial task to measure the lamina compressive and shear strengths (52,53). Also the failure of the first ply of a laminate does not necessarily coincide with the maximum load that the laminate can sustain. In many practical composite laminates first-ply failure may be accompanied by a very small reduction in the laminate stiffness. Local ply-level failures can reduce the stress-raising effects of notches and enhance fatigue performance (54). 

T1-6A1-4V were superior in corrosion-fatigue performance to the type 316L devices even though some fretting and wear occurred in the countersinks. 

Early work on the fatigue strength of various metallic alloys including steels, aluminium alloys, copper alloys and nickel-base superalloys in vacuum and in air clearly demonstrated that fatigue performance improved in... 

Fracture mechanic The fracture mechanics theory developed for metals is also adaptable for use with plastics. The basic concepts remain the same, but since metals and plastics are different they require different techniques to describe their fatigue-failure behaviors. Some of the comments made about crack and fracture influences on fatigue performance relate to the theory of fracture mechanics. The fracture mechanics theory method, along with readily... 

Fatigue data analysis, 13 494-495 Fatigue failures, 13 481, 486-487 Fatigue loads, 13 481 Fatigue performance, sample size and surface finish in, 13.486 487 Fatigue properties... 

Surface-enhanced resonance Raman scattering (SERRS), 21 327-328 advantage of, 21 329 Surface Evolver software, 12 11 Surface excess, 24 135, 136 Surface extended X-ray absorption fine structure (SEXAFS), 19 179 24 72 Surface filtration, 11 322-323 Surface finish(es). See also Electroplating in electrochemical machining, 9 591 fatigue performance and, 13 486-487 Surface finishing agents, 12 33 Surface force apparatus, 1 517 Surface force-pore flow (SFPF) model,... 

Table II compares fatigue performances of the chlorinated, bro-minated, and fluorinated systems.

POSTER TITLE Effect of Friction Stir Welding on the Corrosion Fatigue Performance of Magnesium Alloy AZ31B-H24... 

The fatigue performance of these materials in a pavement cannot be inferred directly from these values of Kx and K2, for the actual fatigue behavior will depend upon such variables as thickness and stiffness and size of tire footprints. In addition, it is well known that laboratory fatigue data does not represent accurately the actual fatigue strength of pavements. A given material in a pavement can take 10-100 times as much strain under seal traffic loads as it can when loaded under laboratory conditions to the same number of load cycles. 

Regarding fatigue performance, an important role is played by polymer processing. Molecular orientations and aging can affect polymers so that they show earlier failure in active media. On the other hand, appropriate orientations can be induced to enhance the ESCR. 

A.R. Chambers, J.S. Earl, C.A. Squires, M.A. Suhot, The effect of voids on the flexural fatigue performance of unidirectional carbon fibre composites developed for wind turbine applications, InternationalJournal of Fatigue 28 (2006), pp. 1389-1398. 

Unique physical properties of halobutyl are retained in brominated p-methylstyrene-isobutene copolymer, but, due to absence of backbone unsaturation, the degradation under irradiation is decreased markedly and the resistance to ozone is outstanding. These improvements, together with thermally stable C-C cross-links, lead to significantly enhanced heat aging and fatigue performances. 

Many investigations of the mechanical properties of ABS and of the nature of rubber toughening in this material have been made and these findings are reviewed and discussed by Bucknall and by Mann and Williamson There have been fewer studies of fatigue performance, and most of these are concerned only with crack propagation in notched specimens Here we are concerned with the... 

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