Papers by Keyword: Tension Strength

Abstract: The paper discusses durability of glass and carbon fibers which are exposed to alkali environment of concrete. Mainly glass fibers are affected by the high alkali environment with pH of concrete exceeding 12.0. The degradation of fibers is reflected by decreasing of its tension strength, while the rate of decreasing is depended on exposition time and temperature. The paper briefly presents results of a large experimental investigation which should specify an influence of alkali ions concentration in a solution on reduction of the mechanical properties of fibers. Reference samples were immersed in a bath with distilled water and the others were stored at ambient air only.

Abstract: The gas cylinder is used in most cases, which is often made from alloy structural steel. When it is used in high pressure gas cylinder, the larger volume, higher weight, and larger length will produce. It is found that both in theoretical and experimental analysis that this kind of material has syntactical mechanical properties such as the tension strength and plastic strength, so it can be reused many times.

Abstract: This article studied the drilling loading method for the tensile strength of irregular small-stone, designed the measuring devices, and addressed the measurement problems of irregular small-stone tensile strength. Based on static equilibrium theory, it analyzed the distribution rule of tensile stress in dangerous section, and established the mechanics model of drilling loading method. In considering the impact rules of characteristic destruction size and round-hole size on the hole-edge stress concentration, on this basis it established the theoretical formulas of measuring the tensile strength of brittle materials. It practically measured the failure load of small drilling bluestone, introduced the failure load into the theoretical measurement formula of brittle material tensile strength, and then obtained the tensile strength of stones, while it measured the tensile strength of non-porous strip specimen. The tensile strength of irregular stones measured by the drilling loading method is basically consistent with the tensile strength obtained from the tensile test of non-porous strip specimen, and therefore the drilling loading method is able to reasonably measure the tensile strength of small stones.

Abstract: Water-soluble substance is an important part of non-rubber substance in natural rubber latex and it has significant influence on the properties of natural rubber. The aim of this paper is mainly to study the composition of small-molecular-weight water-soluble substance (s-WSS) and its effects on the properties of natural rubber films. The analysis of IR and HPLC-MS showed that s-WSS (not including sugar) is composed of C₃H₄N₄O₆, C₇H₁₄O₆, C₁₁H₁₃N₃O₅, C₁₁H₂₀O₇ and C₆H₂₂N_8. While the main component of s-WSS is C₇H₁₄O₆ which is a kind of alcohol. The tensile strength of the prepared composites can be increased at low loading of s-WSS. The tear strength of the prepared composites can be improved by adding s-WSS into natural rubber. The thermal oxidation degradation process of the samples has two stages. Compared with neat natural rubber latex, the initial degradation temperature was decreased significantly in both stages when s-WSS was added. While the degradation temperature range became larger in both stages.

Abstract: Spraying wire was widely used in remanufacturing work piece for worn failure. With the demand of high abrasion resistant wire, new type alloy was developed. The solidification structures of the new high abrasion resistant alloy (HARA) containing Mn, Cr, Si, C and the structure was studied after tension by scanning electron microscopy (SEM). The phase evolution was analyzed by X-ray diffraction and Rockwell hardness evaluated on the hardness testing. The abrasion behavior of HARA alloy used in the liner of wet-grinding machine in metallurgical industry is investigated under impacted energy of 0.5-3 J in acid-ironstone slurry; the test was carried out by a modified MLD-10 tester. The result show that the solidification structures of HARA alloy consist of austenitic Fe and the hardness neared to HRC60. Under the high energy, the wear resistance of HARA alloy is three times more than Mn13. Therefore, the new material has better abrasive wear resistance and lower environmental impact

Abstract: In order to determine the mechanical properties of the carbon/polyurethane composite laminate with splicing ply, the tensile testing were performed on laminate specimens which has been designed specially. The tensile elastic modulus and tensile strength were obtained from the experimental datum. The breakage happened in place of joint gap. The stiffness of the composite laminate was affected by the oblique splicing ply significantly, but the strength is mainly determined by the continuous layers. The laminate is failure in low load. The numerical analyses using linear elastic and progressive damage model were conducted with the commercial the finite element model (FEM) software ABAQUS. The linear elastic FEM is established to calculate the inter-laminar stress. The progressive model is used to predict the strength on the basis of numerical computation. There are three different criteria used here in the strength prediction. By combining the damage model with classical lamination theory, the behavior of laminates under plane stress loading is predicted. The results show that the experimental tests are in good agreement with the finite element simulation.

Abstract: Direct tension strength tests were conducted on chemical vapor deposited silicon carbide microspecimens. Three types of specimens were used: straight gage section, tapered gage section, and notched gage section. The average strengths and standards deviations were: 0.42 GPa ± 0.13 GPa; 0.47 GPa ± 0.16 GPa; and 0.68 GPa ± 0.19 GPa, respectively. The fracture origins were identified by fractographic analysis and were cracks in large grains next to surface grooves from the deep reactive ion etch (DRIE) process used to fabricate the specimens.