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Weld‐bonding combines the physical force‐based process of welding with the chemical force‐based process of bonding or, more properly, adhesive bonding. When done properly, the claim is that a hybrid process results which offers the best of both processes; the high joint efficiency, resistance to diverse and complex loading, and temperature tolerance of welding; the load‐spreading, stress concentration‐softening, and structural damage tolerance of adhesive bonding. And, beyond these individual process attributes, there are claims, or at least predictions, of synergistic benefits in the form of improved energy absorption and fatigue life for demanding applications. However, it is difficult to find reliable data in the open literature to support these real or potential benefits. Furthermore, complications in performing the hybrid process in practice place an even greater premium on process control than normal. This paper explores the question, “Is it all worth it?” The paper delves into the theory underlying weld‐bonding, the facts concerning the process including pluses and pitfalls, and considers where the process could or should go from here.

The purpose of this paper is to study the bonding properties of Larch with water‐based polymer isocynate (WPI) adhesive to provide theoretical instruction for practical production of Larch glued laminated timber with WPI adhesive.

This study adopted Japanese JIS K6806 standard to test bonding properties of Larch with WPI adhesive. Scanning electron microscope was used to observe morphography of Larch surface. Micro photos were adopted to show the penetration of WPI adhesive on the radial and tangential surfaces of Larch.

There was significant difference in bonding strength between Larch radial and tangential glue‐blocks glued with WPI adhesive. Dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was 1.41 times that of Larch tangential glue‐block bonded with WPI adhesive in normal conditions. Wood failure showed that the difference between Larch radial and tangential glue‐block was caused by wood structure of Larch itself.

The research conclusion that the dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was bigger than that of Larch tangential glue‐block bonded in normal conditions. These would be changed if other adhesives were adopted to glue Larch wood.

The conclusion developed in this study provided a practical production instruction for Larch glued laminated timber with WPI adhesive. In order to obtain better bonding properties during the production of Larch glued laminated wood, Larch wood should be sawn into radial boards rather than tangential boards in order to obtain maximum bonding strength of Larch wood.

The paper shows that there was significant difference in bonding strength between Larch radial and tangential glue‐bonded blocks with WPI adhesive. Dry compressing shear strength of Larch radial glue‐block bonded with WPI adhesive was 1.41 times that of Larch tangential glue‐block bonded with WPI adhesive in normal conditions.

This review paper aims to provide a better understanding of formulation and processing of anisotropic conductive adhesive film (ACF) material and to summarize the significant research and development work for the mechanical properties of ACF material and joints, which helps to the development and application of ACF joints with better reliability in microelectronic packaging systems.

The ACF material was cured at high temperature of 190°C, and the cured ACF was tested by conducting the tensile experiments with uniaxial and cyclic loads. The ACF joint was obtained with process of pre-bonding and final bonding. The impact tests and shear tests of ACF joints were completed with different aging conditions such as high temperature, thermal cycling and hygrothermal aging.

The cured ACF exhibited unique time-, temperature- and loading rate-dependent behaviors and a strong memory of loading history. Prior stress cycling with higher mean stress or stress amplitude restrained the ratcheting strain in subsequent cycling with lower mean stress or stress amplitude. The impact strength and adhesive strength of ACF joints increased with increase of bonding temperature, but they decreased with increase of environment temperature. The adhesive strength and life of ACF joints decreased with hygrothermal aging, whereas increased firstly and then decreased with thermal cycling.

This study is to review the recent investigations on the mechanical properties of ACF material and joints in microelectronic packaging applications.

To investigate a new approach for making soy‐based adhesive having appropriate properties for potential application in wood industry.

Three chemicals were used for modifying protein contained in soy flour. According to orthogonal experiment design, nine soy‐based adhesives were prepared. Shearing strength of plywood bonded with these adhesives was measured to evaluate the bonding strength of nine formulas. Based on statistic analysis, the main effect factor and an optimised formula were determined. Further investigation on the modification effect to protein molecule was conducted by Fourier Transform Infrared Spectroscopy. In order to facilitate practical application, the viscosity of optimum formula adhesive was measured to determine possible working life. Three additives were added to optimise formula for reducing mould growth.

Based on soy‐flour mass, the best combination of lime milk, sodium hydroxide (NaOH) and sodium silicate was 10, 2, and 20 per cent, respectively. NaOH was considered the main effect factor on bonding strength, and sodium silicate was of the second importance. The viscosity of the optimised adhesive changed lightly in 2 h, and significantly increased from 2 to 4 h. However, it still could spread on veneer, which indicated a reasonable working life for practical application. Based on soy flour mass, when 0.5 per cent sodium benzoate or 25 per cent phenol formaldehyde was added, mould growth could be restrained after early stage.

Though the studied soy‐based adhesive had a good bonding strength and comparative water resistance, its pH was a little too high, which may cause risks of discolour of light coloured wood. Further study is needed to solve this problem.

The approach provided a bio‐adhesive with good bonding strength, comparative water resistance, reasonable working life, and without formaldehyde emission. Soy‐based adhesive is considered a promising alternate adhesive in wood industry and other applications because of the above mentioned advantages.

It provided a potential way to utilise by‐product of agriculture, soy‐flour, as industrial raw material. This will benefit farmers significantly. Meanwhile, the modified soy‐based adhesive is promising to partly or completely replace urea formaldehyde resin that are mainly used in wood industry, avoiding formaldehyde emission and reducing the dependence on petroleum products.

The purpose of this paper is to present a serial produced industrial robot for thin‐type space solar cells (SSC), which is applied to perform the bonding process of SSC.

An optimized process of adhesive coating and bonding for SSC is designed, based on an analysis of hydromechanics model. In order to perform the process, a novel robot is developed, which mainly consists of a three‐axis Cartesian coordinates' motion platform, coating‐and‐bonding device, solar cell and glass cover orientation plate, control system, pneumatic system, constant temperature module, and industrial personal computer software. The coating and bonding operation is based on the three‐axis Cartesian coordinates' motion and the help of pneumatic system.

Compared with the experimental prototype and handwork, the robot is more effective and reliable for the bonding process of the thin‐type solar cells.

The robot is very useful to realize automatic production of SSC.

The purpose of this study is to investigate the reliability of flip chip joints made with anisotropic conductive adhesives (ACA) on flexible polyimide (PI) and liquid crystal polymer (LCP) substrates.

Six test series using two ACAs and an LCP substrate were made with varying bonding pressure. The ACAs had the same matrix and conductive particles. To lower the CTE of one of the adhesives silica had been added to it. The reliability of the test series was studied in a temperature cycling test. The purpose of these test series was to find the optimal bonding pressure for both the adhesives used. According to the results from these initial tests, further test series were made with both LCP and PI substrates. The reliability of these test samples was studied using a temperature cycling test and a constant humidity test. The adhesion strength of the joints was studied before testing.

Both substrates had excellent reliability during the temperature cycling test. However, the reliability of the PI substrates during the constant humidity test was markedly lower than that of the LCP substrates. Additionally, the adhesion strength of the adhesives on to PI substrates was clearly less.

The work shows how the substrate material used affects the reliability of flip chip joints. In addition, the work shows how the addition of silica to the ACA matrix affects the reliability of the joints.

Adhesively bonded joints are used in many fields, especially in the automotive, marine, aviation, defense and outdoor industries. Adhesive bonding offers advantages over traditional mechanical methods, including the ability to join diverse materials, even load distribution and efficient thermal-electrical insulation. This study aims to investigate the mechanical properties of adhesively bonded joints, focusing on adherends produced with auxetic and flat surfaces adhered with varying adhesive thicknesses.

The research uses three-dimensional (3D)-printed materials, polyethylene terephthalate glycol and polylactic acid, and two adhesive types with ductile and brittle properties for single lap joints, analyzing their mechanical performance through tensile testing. The adhesion region of one of these adherends was formed with a flat surface and the other with an auxetic surface. Adhesively bonded joints were produced with 0.2, 0.3 and 0.4 mm bonding thickness.

Results reveal that auxetic adherends exhibit higher strength compared to flat surfaces. Interestingly, the strength of ductile adhesives in auxetic bonded joints increases with adhesive thickness, while brittle adhesive strength decreases with thicker auxetic bonds. Moreover, the auxetic structure displays reduced elongation under comparable force.

The findings emphasize the intricate interplay between adhesive type, bonded surface configuration of adherend and bonding thickness, crucial for understanding the mechanical behavior of adhesively bonded joints in the context of 3D-printed materials.

Fibre reinforced polymer composites (FRPs) are finding increasing usage in many industrial sectors. Adhesive bonding is often the most attractive joining technique for these materials in terms of structural efficiency and cost of manufacture. However, concerns regarding the lack of reliable design methods, the long term ageing behaviour and the difficulties in non‐destructive evaluation and repair of bonded joints has led to a reluctance to use adhesives in primary structures. DERA has been involved in the assessment of adhesive bonding for joining FRPs for many years. This paper focuses on investigations at DERA into the effects that environment and fatigue loading have on the performance of bonded composite joints, and briefly reviews current approaches to strength and lifetime prediction. It is seen that adhesively bonded composite joints can be significantly affected by the service environment, however, this is highly dependent on the joint type and materials involved.

Focuses on the work of Chantal Bretton, a specialist in adhesive bonding research at Belgian’s steel producer Cockerill Sambre. Explains the benefits of using adhesives in the automotive industry, with modern adhesives being able to stick to metals, even with dirty and greasy surfaces which have not been prepared in any way. Also looks at pioneering uses of adhesive bonding in the building industry. Concludes that adhesive bonding will never replace all the spot‐welding in a car but with the increased use of galvanized steel in car bodywork manufacturers are being forced to look at new assembly methods because it introduces complications into the welding process.

ESTABLISHING A STANDARD SOME twenty‐two years ago Dr de Bruyne invented the Redux system for joining metal to metal in a manner suitable for use in aircraft construction The phenol‐formaldehyde/polyvinyl‐formal formulation of this system is still widely used today. What is it that has made this system such a success through the years?