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An impact test equipment was developed. This equipment is able to produce comparatively low load rate of impact. The impact strength of the acrylic adhesive under low temperature was measured using the developed impact test equipment. By using aluminum alloy as adherend, the equipment can measure the impact strength of acrylic adhesive. The tensile strength of the adhesive under various load rate and low temperature were measured. Conventional equipments were also used for these tests. Relations between the load rate, the test temperature and the tensile strength of adhesive were investigated. As an experimental result, at any case of load rate the tensile strength of the acrylic adhesive increased once with temperature decrease. However, when the temperature decreased lower than a specific value, the strength of the adhesive decreased. The temperature that the strength of the adhesive becomes maximum rises with the increase of the load rate. The change of strength of the acrylic adhesive is influenced by the viscosity of the adhesive itself.

In this study, the effect of surface roughness on glossiness and surface color for a pure titanium and a TiN coating surface was investigated based on the experimental discussions. CIELAB (L*a*b* color system) was applied to the evaluation method of surface color. Specimens were machined so that the arithmetical mean roughness, Ra, is less than 1.0 μm. From the results of experiments, the arithmetical mean roughness, Ra, decreased, as the glossiness, Gs (60°), increased. Especially, the glossiness value in the roughness range Ra?0.2 μm was distributed from 50 to 400. Moreover, the arithmetical mean roughness, Ra, decreased, as the lightness, L*, and a, b chroma, C* ab , decreased. The TiN coated surface with vividness had a pronounced tendency to decreasing lightness, L*, and a, b chroma, C* ab . This was attributable to the smaller difference of elevation of the spectral reflectance curve by reason that the short wavelength was diffused more than the long wavelength.

This paper is investigated experimentally about the effect of topography to the glossiness and surface color in order to characterize a surface texture of aluminum alloy 5052. The surfaces of specimens are machined by using a vertical milling machine, a horizontal milling machine and a shaping machine. Four kinds of specimens are machined by each machine so that the arithmetical mean roughness value, Ra, is less than 1 μm at four cutting conditions. From the results of experiments, the glossiness values of the vertical milling surface and the horizontal milling surface were about the same value, meanwhile the glossiness value of the shaping surface was less than half the value of the others. The surface color of specimens was gray. Especially, The lightness value of surface color, L*, of the horizontal milling surface was the highest value. The surface color was whitish gray of all machined surface. Based on those experimental results, it was summarized that the surface texture of specimen machined various machine could be characterized by the glossiness and surface color. These results could be an effective indicator in choosing the most proper machining method to add value to surface texture.

An impact test equipment was developed to measure the strength of adhesive resins subjected to impact loads at low temperatures. The stress wave propagating the adhesive layer and the adherend was analyzed by the one-dimensional elastic wave theory. It was confirmed that the average stress value in the adhesive layer could be evaluated by the stress value of the adherend. Therefore, the measurement method with this equipment is effective. The impact strength of an acrylic adhesive was evaluated using the developed test equipment. As a result of the impact test, the impact strength of the acrylic adhesive increased once with temperature decrease. However, when the temperature decreased lower than a specific value, the impact strength decreased. It was considered that this phenomenon occurs because the adhesive becomes brittle as the temperature decrease.

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.

In this paper, we carried out an experimental research for establishing the evaluation of metal's surface texture by analysis of surface color. The materials of samples used in the experiment were aluminum alloys (A2017, A5052), stainless steel (SUS304) and copper alloy (nickel silver C7541). The surfaces of samples were burnished by use of waterproof abrasive papers. The surface roughness of samples evaluated by arithmetical mean Ra, root mean square slope RΔq and mean width of the profile elements RSm. The experimental results showed strong correlation for three different roughness parameters. Consequently, “Ra” was used as roughness parameter. As Ra decreased, the glossiness exponentially increased. The evaluation method of surface color was applied to CIELAB. The lightness L* in CIELAB decreased as Ra decreased. Thus, it showed that relationship between L* and Ra inverse correlation between glossiness and Ra. Moreover, surface color of four different materials showed that the chromaticness of blue increased as Ra decreased.

This paper describes a quantitative evaluation method for metal surface texture. We used surface roughness and glossiness as parameters to describe surface texture. Specimen surface roughness was evaluated based on geometrical product specification data taken from japanese industrial standards. The effects of surface roughness on glossiness were investigated by aluminum alloys. The relationship between the glossiness and the roughness height, the period of the roughness profile and the slope for the surface roughness processed by a vertical milling machine were studied for determining if the topography of the surface roughness affects the glossiness. The surface of the specimens were polished using abrasive paper and blasted, so that the arithmetical mean deviation, Ra, was less than 1.00 μm. The effects of roughness on glossiness were investigated on polished surfaces and blasted surfaces. The results show that the surface roughness shape and the glossiness prove to be effective indices for evaluating the surface textures of aluminum alloys.

Experimental equipment was developed in order to measure easily the shear strength of adhesive layers subjected to impact loads. The stress state of an adhesive joint was calculated with the finite element method (FEM). The results calculated from the FEM were compared with those from experiments conducted with the equipment. It was shown that the fracture behaviour of the joint depended on the level of the incident stress wave. When loading a comparatively high incident stress, the adhesive layer fractures mainly with the shear stress. It is considered that the maximum shear stress measured is the shear strength under impact loads. In order to confirm the validity of this evaluation method, the maximum shear stress was compared with the impact shear strength, which was measured using a cylindrical butt joint subjected to impact torsional loads. Both values accorded well. From this we were able to conclude that the shear strength of the adhesive layer subjected to impact loads could be evaluated with this equipment.

The effect of strain rate on the plastic deformation behavior of austempered spheroidal graphite cast iron was studied. The matrix of specimens consisted of mixed banitic ferrite together with retained austenite. Thin-walled tubular specimens were strained under tensile stresses or torsional stresses. It was found that the deformation of austempered spheroidal graphite cast iron under both tensile and torsional stresses did not depend much on strain rate in an elastic region. The results for maximum strain under tensile stresses were scattered because the specimens were thin-walled tubes which had numerous graphite nodules and a few defects. The results of tensile tests of thin-walled tubular specimens were greatly influenced by the shape of specimens and defects, whereas the results of torsional tests were hardly influenced. The ratio of transformed retained-austenite into martensite under torsional stresses did not vary with strain rate. It was presumed from this result that work hardening affected an increase of yield stress and torsional strength.