Adhesive Butt Joints Research Articles

Stress analysis and strength estimation of butt adhesive joints of dissimilar hollow cylinders under impact tensile loadings

The stress variations in butt adhesive joints of dissimilar hollow cylinders subjected to impact tensile loadings are analyzed in elastic and elasto-plastic deformation ranges using a finite element method (FEM). The FEM code name employed is DYNA3D. The effects of Young's modulus ratio between dissimilar adherends and the adhesive thickness on the stress variations at the interfaces are examined. In addition, the process of rupture at the interfaces of the joint is simulated. The stress distributions in the joints under static loadings are also analyzed by FEM. The characteristics of the stress variations in the joints under impact loadings are compared with those in the joints under static loadings. Also, the joint strengths under impact loadings are estimated by elasto-plastic FEM. It is found that the maximum value of the maximum principal stress σ 1 occurs at the outside edge of the lower interface. It is also found that the maximum principal stress σ 1 at the lower interface decreases as the adhesive thickness increases. The characteristics of the joints under impact loadings are found to be opposite to those under static loadings. Furthermore, differences in the characteristics of the stress variations are shown between the dissimilar joints and the similar joints. In addition, the experiments were carried out to measure the strain response and strains in the butt adhesive joints under both impact and static loadings using strain gauges. Furthermore, joint strengths under both impact and static loadings were measured. Fairly good agreements are observed between the numerical and the measured results.

104 曲げモーメントを受ける層内に円形剛体充填物を有する突合せ接着継手の二次元応力解析

104 曲げモーメントを受ける層内に円形剛体充填物を有する突合せ接着継手の二次元応力解析

Stress Analysis and Strength of Butt Adhesive Joints of Dissimilar Hollow Cylinders Under Impact and Static Tensile Loadings

衝撃引張り荷重を受ける異種材料中空円筒突合せ接着継手の応力変化状況を，有限要素コード DYNA3Dを用いて有限要素解析した。上部被着体端部を全方向に拘束し，下部被着体端部に取り付 けられた連結棒を有する円形フランジに重錘を自由落下させることにより継手に衝撃引張り荷重を発生させた。その結果，下部接着界面外周において最大主応力の値が最大となった。また，下部と上部 の被着体の縦弾性係数比E2/E，及び接着層厚さ2h3の影響について調べ，縦弾性係数比E2/E1が小さくなるほど，すなわち下部被着体の縦弾性係数E2が小さくなるほど，接着層厚さ2h3が大きくなるほど下部接着界面外周部における最大主応力の最大値が小さくなった。さらに，有限要素コードMARC を用い，静的荷重を受ける場合についても解析を行い，衝撃荷重作用時の接着界面応力特性と比較したところ両者の間では異なった特性を示した。ひずみ応答に関する実験を行い，実験結果と解析結果 はかなりよく一致した。さらに衝撃及び静的荷重下での継手強度についても計算と実験の両面より検討し，両荷重下での継手強度特性を明らかにした。

102 静的引張り荷重を受ける層内に充填物を有する接着継手の有限要素応力解析と強度推定

102 静的引張り荷重を受ける層内に充填物を有する接着継手の有限要素応力解析と強度推定

154 衝撃引張り荷重を受ける層内に充填物を有する突合せ接着継手の FEM 応力応答解析

154 衝撃引張り荷重を受ける層内に充填物を有する突合せ接着継手の FEM 応力応答解析

519 衝撃曲げモーメントが作用する中空円筒突合せ接着継手の有限要素応力応答解析

519 衝撃曲げモーメントが作用する中空円筒突合せ接着継手の有限要素応力応答解析

ゴム変性エポキシ接着剤により接合された突合せ接着継手の損傷挙動

In the present study, damage behavior in the adhesive layer of adhesive butt joints bonded with rubber-modified epoxy was investigated by using an anisotropic damage theory. In the experiments, the stress-strain curves of the bulk specimens and the adhesive layer in the butt joints were measured by loading-unloading tests at a relatively low strain rate. The values of damage parameter D1 in the maximum principal stress direction were obtained from the measured stress-strain curves for the specimens. The relation between D1 and the strain energy density given to the specimens was investigated in order to compare the damage behavior of the butt joint and bulk specimens. From the results, it was found that the strain energy density of the specimens given until they break increased with rubber contents, but their damage behaviors were almost the same. It was also found that the strain energy densities of the specimens at their fracture were almost the same but the damage parameter D1 of the butt joint specimen was higher than that of the bulk specimen over the full range of strain energy.

107 内圧と一様温度変化を受けるカップリングカラー付き突合せ接着管継手の強度

107 内圧と一様温度変化を受けるカップリングカラー付き突合せ接着管継手の強度

FEM stress analysis and strength of adhesive butt joints of similar hollow cylinders under static and impact tensile loadings

The stress wave propagations in butt adhesive joints of similar hollow cylinders subjected to static and impact tensile loadings are analyzed in elastic and elasto-plastic deformation ranges using the finite-element method (FEM). The impact loading is applied to the joint by dropping a weight. The upper end of the upper adherend is fixed and the lower adherend of which the lower end is connected to a guide bar is subjected to the impact loading. The FEM code employed is DYNA3D. The effects of the adhesive thickness and Young's modulus of the adhesive on the stress wave propagation at the interfaces are examined. In addition, the characteristics of the joints subjected to impact loadings are compared with those of the joints under static loadings and the joint strengths are estimated by using the interface stress distributions. It is found that the maximum value of the maximum principal stress, σ1 occurs at the outside edge of the interface of the lower adherend to which the impact loading is applied. The maximum value of the maximum principal stress, σ1 increases as Young's modulus of the adhesive increases when the joints are subjected to impact loadings. It is found that the characteristics of the joints subjected to impact loadings are opposite to those subjected to static loadings. In addition, experiments were carried out to measure the strain response of the butt adhesive joints subjected to impact and static tensile loadings using strain gauges and the joint strengths were also measured. Fairy good agreements are observed between the numerical and the measured results.

334 Stress analysis of butt adhesive joints of dissimilar hollow cylinders under impact tensile loadings

334 Stress analysis of butt adhesive joints of dissimilar hollow cylinders under impact tensile loadings

Finite Element Stress Response Analysis and Strength of Butt Adhesive Joints of Similar Hollow Cylinders Subjected to Impact Tensile Loadings

衝撃引張り荷重を受ける同種材料の中空円筒突合せ接着継手の応力伝播状況を，有限要素コードDYNA3Dを用いて有限要素解析した。上部被着体端部を全方向に拘束し，下部被着体端部に取り付けられた連結棒を有する円形フランジに重錘を自由落下させることにより衝撃引張り荷重を発生させた。その結果，下部接着界面外周(r=7.5，z=-0.05)で最大主応力の値が最大となった。また，被 着体と接着剤の縦弾性係数比E1/E2および接着層厚さ2h2の影響について調べ，縦弾性係数比E1/E2が大きくなるほど，すなわち接着剤の縦弾性係数E2が小さくなるほど，接着層厚さ2h2が大きくなるほど最大主応力の最大値が小さくなった。さらに，有限要紫コードMARCを用い，静的荷重を受ける場合についても解析を行い，衝撃荷重作用時の接着界而応力特性を比較したところ両者の間では異なった特性を示した。ひずみ応答に関する実験を行い，実験結果と解析結果はかなりよく一致した。さらに衝撃および静的荷重下での継手強度についても計算と実験の両面より検討し.FEM計算により強度を推定できることを示した。

106 カップリングカラー付き突合せ接着管継手の強度評価

106 カップリングカラー付き突合せ接着管継手の強度評価

Photoelastic thermal stress measurements in scarf adhesive joints under uniform temperature changes

This study deals with the investigation of thermal stresses and delamination growth in scarf joints under a uniform temperature change by photoelastic measurements and a two-dimensional finite element analysis. The adherends were fabricated from aluminum plates, and an adhesive layer was modeled and fabricated from an epoxide resin plate. The adherends and the epoxide resin plate were bonded using a heat-setting and one-component-type adhesive. The adhesive was cured at 85 °C and cooled down to room temperature. The thermal stress was then generated in the scarf joint under a temperature change and measured by photoelasticity. After the scarf joints were cooled in a stepwise manner, the delamination growth, which initiates from the edge of the interface, was measured. It was found that the delamination initiates from the edge of the interface with the acute angle side and it never initiates from the edge with the obtuse angle side. When the scarf angle is 90°, i.e. in adhesive butt joints, the resistance against the delamination is minimal. The thermal stresses in the scarf joints with a thin adhesive layer were also analyzed. It was found that the thermal strength increases as the adhesive thickness decreases. The stress singularity near the edge of the interface was calculated from the stress distributions in the joints with different scarf angles. As a result, it was found that the stress singularity in the scarf joints under thermal loads is quite different from that under static tensile loads.

313 衝撃荷重を受ける中空円筒突合せ接着継手の有限要素応力解析(オーガナイズドセッション : 接着接合の力学)

313 衝撃荷重を受ける中空円筒突合せ接着継手の有限要素応力解析(オーガナイズドセッション : 接着接合の力学)

251 衝撃引張り荷重を受ける欠陥及び充填物を有する突合せ接着継手の有限要素応力応答解析(GS-4 接着・接合・継手)

251 衝撃引張り荷重を受ける欠陥及び充填物を有する突合せ接着継手の有限要素応力応答解析(GS-4 接着・接合・継手)

303 衝撃荷重を受ける中空円筒突合せ接着継手の有限要素応力解析(材料力学-数値解析)

303 衝撃荷重を受ける中空円筒突合せ接着継手の有限要素応力解析(材料力学-数値解析)

314 衝撃引張り荷重を受ける充填物を有する突合せ接着継手の有限要素応力応答解析(オーガナイズドセッション : 接着接合の力学)

314 衝撃引張り荷重を受ける充填物を有する突合せ接着継手の有限要素応力応答解析(オーガナイズドセッション : 接着接合の力学)

501 一様温度変化と内圧を受ける接着管継手の強度評価 : カップリングカラー付き突合せ接着継手の強度(OS 接着・界面)

This study deals with the stress analysis and the strength evaluation of an adhesive butt joint combining a coupling collar when the joint is subjected to an internal pressure and a temperature change. The stress distributions at the interface between the adherends and the adhesive in the joint are analyzed by using the axisymmetric finite element method (FEM). In addition, the rupture test of the joint was carried out by applying an internal pressure and a temperature change to the joint. From the numerical calculation and the experiment, strength of adhesive butt joint combining a coupling collar is estimated by using the stress distribution at the interface obtained from the FEM analysis.

K-0330 メッシュレス法による異材接着突合せ継手の応力解析(G01-3 メシュレス法・ボクセル法)(G01 計算力学部門一般講演)

We propose the methods to apply the EFGM (Element Free Galerkin Method) developed by T. Belytschko et al. to the stress analysis of Adhesive Butt Joints, and analyzed the interface stresses in the three-dimension. We divide the model of analysis to the domain of the same materials as Material1, Material2 and Adhesive, and applied the EFGM to Material1, Material2 and Adhesive respectively. Then, each displacement of Materiall and Material2 must be continuity on interface. So we restrain the displacements on the interface by the penalty method.

Evaluation of impact tensile properties of adhesive butt joints

The tensile properties of adhesive butt joints under impact loading are measured with a modified split Hopkinson bar using a solid butt joint specimen. A commercially available cyanoacrylate adhesive (commonly termed an instantaneous adhesive) and two different adherend materials (or substrates) are used in the adhesion tests. The impact tensile strength of the cyanoacrylate adhesive butt joints is determined from the applied tensile stress at failure initiation. The impact energy absorbed is obtained by numerical integration of dynamic load-displacement data. Comparative tension tests at low rates of loading are performed on an Instron testing machine. The effects of loading rate, adherend material and thickness of the adhesive layer on the tensile strength and energy absorption of the cyanoacrylate adhesive butt joints are examined in detail.