We study the transverse oscillatory modes of nanomechanical silicon nitride strings under high tensile stress as a function of geometry and mode index m≤9. Reproducing all observed resonance frequencies with classical elastic theory we extract the relevant elastic constants. Based on the oscillatory local strain we successfully predict the observed mode-dependent damping with a single frequency...

Strength data from a recently developed apparatus for measuring long-length fiber strength distributions are analyzed in terms of proof test theory for truncated distributions. Data are fitted using Weibull statistics and scaled for bending and tensile lengths ranging from 1 meter to 100 kilometers. Most tensile applications require strength data near the proof stress level. For failure probabi...

dual phase steels with different martensite volume fraction and morphology were tensile tested at a temperature range of 25 to 5500c. stress-strain curves of all steels showed serration flow at temperatures of 250 and 3500c, and smooth flow at the other temperatures. both yield and ultimate tensile strengths increased with increasing testing temperature up to about 4500c and then decreased at h...

Tensile creep of concrete at early ages is one of the important factors that affect the stress of restrained and partly restrained concrete. But only few data are available on tensile creep of concrete. The effect of ground slag on tensile creep was studied using lever-type tensile creep tester. Early age tensile basic creep of concrete loaded at the age of 3 days was researched. Results show t...

While understanding the properties of materials under stress is fundamentally important, designing experiments to probe the effects of large tensile stress is difficult. Here tensile stress is created in thin films of potassium (up to 4 atomic layers) by epitaxial growth on a rigid support, graphite. We find that this "simple" metal shows a long-range, periodic "herringbone" reconstruction, obs...

Two types of heat treatments are commonly used for alloy 901, one to optimize resistance to creep and rupture and the other, to improve tensile and fatigue properties. Solution and aging-treatment parameters (temperature, time, quench) for both types of heat treatment were varied within the ranges permitted by common specifications to define heat treatments resulting in improved combinations of...

The fracture strengths and elastic moduli of arc-grown multi-walled carbon nanotubes (MWCNTs) were measured by tensile loading inside of a scanning electron microscope (SEM). Eighteen tensile tests were performed on 14 MWCNTs with three of them being tested multiple times (3 , 2 , and 2 , respectively). All the MWCNTs fractured in the Bsword-insheath’’ mode. The diameters of the MWCNTs were mea...

Almfrmt-The relations of II ‘mate tensile stress and strain and modulus of elasticity to 2 col@en fiber orieatotioa an dtgrue of calcifkation were studied in thirty-six standardized specimens of unembahned cortical bone from adult human tibias. Highly significant positive comhtionswmfoundkovtcnt~tsatssandsrrrir!aad~afdukoneonsiatbe break area. A similar correlation occurred brrtween tensile sti...

In order to investigate the effect of applied stress on mechanical properties in metallic glasses, nanoindentation tests were conducted on elastically bent Zr-Cu-Ag-Al metallic glasses with two different structure states. From spherical P-h curves, elastic modulus was found to be independent on applied stress. Hardness decreased by ~8% and ~14% with the application of 1.5% tensile strain for as...

In a tensile test of a bar or fiber formed from a transversely isotropic viscoelastic material, the initial motion in regions away from the clamps is a homogeneous uniaxial extension. If the applied tensile load is “tame” in the sense that it is given by a piecewise smooth function of time, then during the early stages of loading, the homogeneous extension of the specimen is also tame. It is, h...