Uncertainties and dynamic problems of bolted joints and other fasteners

This paper describes the establishment of an evaluation method for metal surface texture. The evaluation parameters used for surface texture were roughness, glossiness and color. Seven sample materials were studied: aluminum alloys (A2017, A5052), stainless steel (SUS304) and copper alloys (tough pitch copper C 1100, brass C2801, phosphor bronze C5191 and nickel silver C7541). The surfaces of all specimens were polished using waterproof abrasive papers. The correlation of the surface texture parameters for all specimens was investigated experimentally. The surface roughness of specimens was evaluated using the arithmetical mean roughness "Ra". The method for evaluating surface color was assessed by using CIELAB color space. The CIELAB color space is one of a uniform color space defined by CIE (Commission Internationale de l'Eclairage) in 1976. The results indicated that as surface roughness value "Ra" decreased, as the glossiness value "Gs(60°)" increased exponentially. The lightness value "L*" of the CIELAB color space decreased, as surface roughness value "Ra" decreased. Thus, the relationship between the lightness value "L*" and surface roughness value "Ra" showed an inverse correlation with the glossiness value "Gs(60°)" and surface roughness value "Ra". Moreover, the surface color showed that the blue hue increased, as the surface roughness value "Ra" decreased for all seven types of materials.

https://www.jstage.jst.go.jp/article/matertrans/45/4/45_4_1027/_pdf

Experimental relationships between surface roughness, glossiness and color of chromatic colored metals

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis and simulation of adhesive bonding, soldering and brazing processes. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subjects that were published in 1976 - 1996. The following topics are included: adhesive bonding - stress analysis of adhesive bonding in general, stress analysis and design of specific bonded joints, fracture mechanics and fatigue analysis, destructive and nondestructive evaluation of bonds, other topics; soldering - thermal stresses and deformation analysis of solder joints, fracture mechanics aspects and fatigue analysis of solder joints, solder joint reliability; and brazing - finite element analysis and simulation.

https://www.giref.ulaval.ca/~deteix/bois/documents_references/article10.pdf

Finite element analysis and simulation of adhesive bonding, soldering and brazing: A bibliography (1976 - 1996)

Analysis and design of adhesive-bonded tee joints

Strength of adhesively bonded scarf joints between glass fibre-reinforced plastics and metals

Color, texture and the tactile senses are recognized as the evaluation factors for a metal surface. In the present, though those factors are widely used as the popular comprehensive indexes to characterize a metal surface, evaluation of these factors are mainly referred to the terms of touch or visual look. From a customer point of view, particular factors to characterize a metal surface and its numerical expression may not only be helpful to judge its commercial value, but also to avoid unnecessary trouble on judging its appearance. Moreover, these quantitative evaluations are able to improve reproducible accuracy. This paper describes the quantitative evaluation method of a surface texture for metals. As the specimens, aluminum alloy that is one of the popular metals of the exterior material for industrial products are used. The surface textures have been measured by a non-contact 3D surface profiler and the results have been compared with nickel silver alloy and stainless steel. First, the surface textures are measured by stylus method and optical interferometer method to find the relationship between those two measurement methods. Then, as x surface property parameters to express transcriptive property of shot blasted, upper material ratio Sr1 and lower material ratio Sr2 were concluded to be effective.

https://www.jstage.jst.go.jp/article/jilm/61/5/61_5_187/_pdf

Evaluation parameters of surface texture on shot-blasted surfaces

Inflatable space structures are expected to be a promising candidate for future large-scaled space structures because of the compactness at the launch stage and the simple extension mechanism. In this paper, the feasibility of an inflatable structure was examined utilizing the expansion force of foam materials as the inflation thrust. As a trial inflatable space structure, an extensible mast, which was made of foam material covered with an aluminum sheet or a carbon fiber cloth was chosen. This paper describes foaming behavior of the material in space. As a first report of the study, intensive discussion was placed upon the effect of low pressure environment on the expansion behavior. The expansion behavior of foam material appeared to be controlled mainly by the pressure difference between the inside and outside of foams. It was found that the fracture of foams could be prevented and the density of the foam material could be controlled even in the low pressure environment by controlling the amount of blowing agent. The effect of tube geometry on the expansion behavior was also discussed.

Foaming Behavior of Polyurethane to be Applied to Inflatable Space Structures under Low Pressure Environment.

The deformation and strength of single lap joins having different thicknesses of adherends were investigated both analytically and experimentally. The strain distributions of the joints of carbon steel bonded with epoxy resin under tensile shear loading were analyzed by the finite element method. The strength of the joints was predicted by applying the strength laws for adherend, adhesive layer and their interfaces to the calculated stress distributions. The calculated strain distributions in the joints were in good agreement with the experimental observations. The predicted strengths of the joints were close to the measured values by experiments. On the basis of the results obtained, the effect of the adherend thickness on the joint strength is discussed.

Strength Evaluation of Asymmetric Single Lap Joints : 1st Report, Effects of the Adherend Thickness

Nonlinear fracture behavior of stepped-lap bonded joints is studied. The joints used have adherends of eight kinds of metals : three types of carbon steel, and four types of aluminum alloy and brass. The joints also have various thicknesses, lap lengths and step numbers. The effect of Young's modulus and yield strength of adherend material on the joint strength is calculated by means of elasto-plastic finite element method analysis. It is found that the strength of the joint which yields at an adherend corner is nearly equal to the yield strength of the adherend material, because the displacement of the adhesive layer increases abruptly after the adherend yield, and exceeds the layer's deformation capacity. The joint strength diagrams obtained by the strength prediction method applying our adhesion criteria show good agreement with the experimental results for all the present joins having various dimensions and materials.

Toshio Sugibayashi

Papers

Evaluation parameters of surface texture on shot-blasted surfaces

Foaming Behavior of Polyurethane to be Applied to Inflatable Space Structures under Low Pressure Environment.

Strength Evaluation of Asymmetric Single Lap Joints : 1st Report, Effects of the Adherend Thickness

Fracture Behavior and Strength of Stepped-Lap Bonded Joint with Adhesive Resin Under Tensile Loading.

Evaluation Method for Shear Strength of Adhesives Using Single Lap Joints