Papers by Keyword: Structural Adhesive

Abstract: An high performance two-component structural anchor adhesive based on vinyl ester resin is synthesized by adding the toughener to improve the material brittleness and bringing in chemical heat source to reduce the affection of the environment on chemical reaction and it can be cured in the damp or in the environment with water by adding the water-absorbable filler.Compound stabilizer consisted of inhibitor and oxalic acid improve the stability of the pro-accelerated vinyl ester resin.The adhesive exhibites high-early-strength developing, excellent bong strength with “can’t dry”substrate and can cure rapid in lower temperature.it allows construction crews to install threaded rod or rebar in concrete that is too damp or soaked to bond with other adhesives.

Abstract: Currently only few methods exist for thin steel sheet testing, especially based on fracture mechanics concept. Charpy impact test is one of the most used method for testing notch toughness and fracture behaviors because of the simplicity and the other advantages [. This article deals with toughness testing of automotive ultra high strength steel sheets (UHSS). Several standard types of toughness test that generate data for specific loading conditions and/or component design approaches exist. Two definition of toughness will be discussed: i) Charpy V-notch toughness, method includes joining of thin steel sheets to one compact unit and ii) material (tensile) toughness [. Two steels were used, DP1000 and 1400M of 1,8 mm thickness and two joining techniques: bonding with adhesives and joining with holders. Effect of material, joining technology, structural adhesives, and number of joined plates on the toughness values was quantified at the room temperature. Toughness of steels by the tensile test was added for comparison. Fracture surface was observed using scanning electron microscope analysis.

Abstract: In this paper, we research wire mesh and polymer mortar strengthening of the wire rope end which use MLJ building structural adhesive anchorage in experiment. This text discusses the building structural adhesive for wire rope anchorage performance, through the experiment and data analysis showed that the modified structural adhesive anchorage cable can give full play to the wire rope high strength properties.

Abstract: Abstract. Structural adhesively bonded and spot welded structures in a car body will experience cyclic loading resulting in degradation, especially in energy absorption performance of welded terms. This paper is focused on the degradation of adhesively bonded and weld-bonded box beams versus equivalent spot welded samples. In the first part of this paper, results from the experimental testing of box beams with different joint methods under cyclic torque are presented. The torsional stiffness of box beams is shown to degrade and box beams with different joint methods show different performance. In the second part, 3-point bending crash test results show the different performance of energy absorption with different joint methods. Bonded and weld-bonded box beams with toughened structural adhesive maintain energy absorption performance compared to the original level, while spot welded profiles show a significant decrease.

Abstract: Nano SiO2 is employed in this research to modify the epoxy resin structural adhesives, and the law how different volumes of nano material influence the tensile and adhesive properties is studied. The experimental results indicate that incorporation of Nano SiO2 improves the tensile and adhesive properties of structural adhesives, yet if its volume fraction exceeds 5%, the modified result is undeniable. Moreover, high-temperature processing of structural adhesives will achieve better properties.

Abstract: A method is described for measuring the glass transition temperature (Tg) of epoxy joints bonding ceramic (SiC) substrates. This method is based on the strain measure of a single-lap joint subjected to a temperature variation. The resulting displacement (d) is observed as a function of the temperature (T) by means of a contact strain gauge extensometer. Thus Tg value can be determined using (d-T) curves recorded. The influence of joint parameters (joint thickness and overlap length) and of other parameters such as the applied load and the surface state of substrates were studied for a structural epoxy adhesive showing different thermomechanical behaviours. The results show that it is possible, with appropriate experimental conditions, to measure Tg with this method and to find Tg values similar to those found by classical techniques such as the static thermomechanical analysis (TMA) and the differential scanning calorimetry (DSC). This method shows similarities with TMA, but it has the advantage to allow the thermomechanical analysis of adhesives without destructive sampling of joints.

Abstract: One of the greatest drawbacks to predicting the behaviour of bonded joints has been the lack of reliable data on the mechanical properties of adhesives. In this study, methods for determining mechanical properties of structural adhesive were discussed. The Young’s modulus, Poisson’s ratio and tensile strength of the adhesive were tested by dogbone specimens (bulk form) and butt joint specimens (in situ form). The shear modulus and shear strength were test by V-notched specimens (bulk form) and thick adherend lap-shear (TALS) joint specimens (in situ form). The test results show that the elastic modulus provided by the manufacturer is too low, the dogbone specimen is better than the butt joint specimen to test the tensile strength and elastic modulus and the TALS joint specimen is better than the V-notched specimen to test the shear strength.

Abstract: This paper highlights a systematic investigation (related to percentage addition of solvents) of finding the appropriate solvent to reduce the viscosity of the structural grade of resin (AV138M) within castable range to effectively disperse the nanofillers (Carbon Nano Powder - CNP and Multi Walled Carbon Nano Tubes - MWCNT). AV138M + HY998/CNP and AV138 + HY998/MWCNT were cast within-process degassing using a vacuum pump of capacity 4 torr. High energy sonic waves (27kHz) were used for dispersion. Morphological studies were undertaken to analyze the uniformity in dispersion of nano fillers. The cured specimens were subjected to: Resistivity measurements using a Resistivity Meter, Glass Transition Temperature (Tg) using a Differential Scanning Calorimetry (DSC) and Tensile properties using UTM. The properties have been determined for the nanocomposites with different wt % of the fillers. It has been found that for 0.6 wt % of filler (CNP / MWCNT), there is an increase in UTS of 10 times for MWCNT compared to CNP; for 1.0 wt % of the fillers, the Tg improved by 10 °C for MWCNT and by 4 °C for CNP when compared with neat resin. Both CNP and MWCNT showed drop in electrical resistivity of the neat resin; a drop to the extent of 10 3 has been achieved with 1 wt % MWCNT and the same was 2 wt % in case of CNP.

Abstract: The demand for safer, lighter and more fuel efficient vehicles has led to the market entry of light weight construction, with the use of advanced high strength steels, engineering plastic and light weight metals. Maximum weight savings potential will be limited if these are used in isolation. Chemistry based structural adhesives and foams enable the intelligent use of all three weight saving methodologies to overcome the problems of safety, quality and high processing cost.