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The purpose of this paper is to determine the effect of Imersol Aqua impregnation of Scotch pine, Oriental spruce, and Uludağ fir on the surface adhesion strength of various types of varnishes. The finding obtained would benefit the manufacturers of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.

For this purpose, test samples were prepared from Scotch pine, Oriental spruce, and Uludağ fir woods that met the requirements of ASTM D 358. The samples were impregnated with Imersol Aqua using short‐, medium‐, and long‐term immersion techniques according to ASTM D 1413 and the manufacturer's instructions. After impregnation, surfaces were coated with synthetic, acrylic, polyurethane, and water‐based varnishes in accordance with ASTM D 3023 standards. After the varnishing process, the adhesion strength of the samples was determined in accordance with ASTM D 4541.

It was also found that among the wood samples, the adhesion strength was highest in Scotch pine and lowest in Uludağ fir. The synthetic varnish produced the highest adhesion strength, whereas polyurethane and acrylic varnishes had the lowest adhesion strength. The adhesion strength was highest after medium‐term immersion and lowest after long‐term dipping. The highest adhesion strength (4.299 MPa) was produced by a combination of Scotch pine, medium‐duration immersion, and the use of a wood‐based varnish. The lowest adhesion strength (2.090 MPa) resulted from the combination of Uludağ fir, long‐term immersion, and a water‐based varnish.

Impregnating woods using materials with appropriate water repellent, biotic, and abiotic effects before the application of varnishes and paints is important for long‐term protection against photochemical degradation, dimensional changes, biological factors, and fire.

The effect of a varnish on surface adhesion strength can determine the usefulness of the varnish.

Improving surface adhesion of some varnishes via medium‐term impregnation with Imersol Aqua impregnation should be used on Scotch pine, Oriental spruce, and Uludağ fir woods which could be used in the manufacturing of building materials and furniture, where the surface adhesion strength of water‐based varnishes is a concern.

Based on the mechanical model of typical shear tests, this study aims to propose the test principle and method of freshwater/seawater ice adhesion shear strength of carbon ceramic brake pads for amphibious aircraft, designs and builds the test equipment, prepares the freshwater/seawater ice samples and completes the tests.

This study examines the influence of the icing process, mechanism, temperature and freshwater/seawater on ice adhesion shear strength of carbon ceramic brake pads and puts forward a test method for the freshwater/seawater ice adhesion shear strength of amphibious aircraft brake pads.

The obtained results examine the influence of the icing process, mechanism, temperature and freshwater/seawater on ice adhesion shear strength of carbon ceramic brake pads. The adhesion shear strength of frozen freshwater and of the seawater of Dalian, Qingdao, Fuzhou and Zhuhai on the surface of aircraft brake pads is measured at –10 to –50°C. It is found that the shear strength of freshwater increases first and then decreases with the decrease of temperature. The adhesion shear strength of seawater; however, increases mainly linear with the decrease of temperature.

The value of this paper is that the test method proposed and test results for the freshwater/seawater ice adhesion shear strength of amphibious aircraft brake pads provide technical support for the anti-icing design of amphibious aircraft brake devices.

The extension of the vacuum-assisted multipoint moulding (VAMM) technology to a broader field of geometries makes it necessary to extend it with attachments to the enhanced vacuum-assisted multipoint moulding with additive attachments (EMMA) technology. Therefore, it is necessary to build additive manufactured attachments on a curved silicone surface by fused filament fabrication (FFF). The main challenge of FFF on a silicone-made build plate is the adhesion of the part on the build plate. Hence, the purpose of this paper is to find suitable and reliably manufacturable material and adhesion promoter combinations for the use of the FFF on silicone build plates.

The combinations of seven different filaments and four adhesion promoters were investigated with an experimental study. Therefore, four different specimen geometries were built with the different combinations and tested in a tensile test, and some of the specimens were analysed with a confocal laser scanning microscope (CLSM).

This study proves that the FFF on unheated silicone building plates is possible for several material combinations. As a filament material, polylactide can reliably be manufactured with all of the investigated adhesion promoters on the silicone build plate. Thereby, the highest adhesion strengths were achieved with an adhesive foil as an adhesion promoter, whereas the glue stick is the most appropriate solution. The investigations with the CLSM showed that there are large differences in the manifestation of the first layer depending on the adhesion promoter used.

To the best of the authors’ knowledge, this study is the first to demonstrate the manufacturing of FFF-made attachments on silicone build plates for the EMMA process. This paper provides measurement data on the build plate adhesion of the attachments on silicone-made build plates.

The paper's aim is to investigate improvement of strength and adhesion of silicone‐acrylic hybrid systems.

The presence of Si‐C bonds in phenyl silicone should be able to improve strength, adhesion and thermal properties of phenyl silicone‐acrylic polyol coating. Different weight ratios of phenyl silicone and acrylic polyol resins were blended in order to obtain the composition for optimum strength, adhesion and thermal properties. Strength was evaluated using an impact resistance tester. Coating adhesion was studied by measuring the contact angle and performing cross hatch cutting. The thermal properties were studied using differential scanning calorimetry.

Blending phenyl silicone intermediate resin with acrylic polyol resin showed significant improvement in strength and adhesion properties compared to pure acrylic polyol resin. This paper shows that the composition of such coatings influences the glass transition temperature (T_g), which in turn affects the strength and adhesion properties of the coatings. The coating consisting of 30 per cent silicone resin and 70 per cent acrylic resin showed good adhesion and impact resistance properties on cold roll mild steel panels.

Findings may be useful in the development of heat resistant and anti‐corrosion paints.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resins.

Durability and functionality of the coating critically depend on the strength and adhesion properties of the materials. This may be a useful source of information for the development of organic‐inorganic coatings.

For TAB tapes and flex circuitry, laminates with adhesives (3‐layer laminates) are commonly used. The drawbacks of adhesives are well known. Adhesiveless flexible copper‐polyimide laminates (2‐layer laminates) could avoid such disadvantages. Two‐layer thin film laminates may be produced using sputtering technology. Good adhesion strength between the copper and the polyimide film may be achieved by means of special plasma treatment. The advantages and disadvantages of 2‐layer flexible thin film laminates are discussed in this paper, along with their different production methods. The adhesion strength of 2‐layer laminates in comparison with 3‐layer laminates will be pointed out. Future uses of 2‐layer flexible thin film laminates will be considered, along with their benefits.

A silver‐palladium thick film conductor for aluminum nitride (AlN) substrate has been developed. This conductor film on AlN ceramics had low sheet resistivity, high adhesion strength and good wettability with Pb‐Sn solder. The frit powder of lead borosilicate glass was used as inorganic binders to enhance the adhesion between the conductor and ceramics. After sintering the conductor film connected with the AlN substrate through frit bonding, no transition phases but a multilayer structure is present in the interface. The softening point of the glass was important to the adhesion strength of conductor film. In order to achieve good adhesion, it is necessary that the glass has a proper softening point (about 500‐650°C).

Peel adhesion of an epoxy filleting compound and Parylene C conformal coating to plasma treated, solder mask coated substrates and the apparent contact angle of water on the treated surfaces were evaluated. No significant improvement was achieved in the case of the epoxy filleting adhesive for most solder mask coatings studied. On the other hand, Parylene C peel adhesion significantly increased after substrates were treated with air plasma and reached the level of Silane coupling agent primed substrates. This was in contrast to the decrease in Parylene adhesion to argon plasma treated substrates in comparison with the non‐treated substrates. This was related to the oxygen functionalities created on the surfaces by the air plasma versus the ablative nature of the argon plasma. No clear correlation was found between peel strength and the water contact angle in the case of the epoxy adhesive, while for the Parylene conformal coating peel strength achieved its maximum value at the middle of the contact angle range which resulted from the pretreatments applied in this study. It is concluded that air plasma is a very efficient solder mask pretreatment for Parylene conformal coating that can replace Silane primer. Also, if a calibration curve is established for each solder mask‐adhesive and solder mask‐coating system, the apparent water contact angle can serve as a convenient quality control tool for printed circuit finishing processes.

Anisotropic conductive film (ACF) is now an attractive technology for direct mounting of chips onto the substrate as an alternative to lead‐free solders. However, despite its various advantages over other technologies, it also has many unresolved reliability issues. For instance, the performance of ACF assembly in high temperature applications is questionable. The purpose of this paper is to study the effect of bonding temperatures on the curing of ACFs, and their mechanical and electrical performance after high temperature ageing.

In the work presented in this paper, the curing degree of an ACF at different bonding temperatures was measured using a differential scanning calorimeter. The adhesion strength and the contact resistance of ACF bonded chip‐on‐flex assembly were measured before and after thermal ageing and the results were correlated with the curing degree of ACF. The ACF was an epoxy‐based adhesive in which Au‐Ni coated polymer particles were randomly dispersed.

The results showed that higher bonding temperatures had resulted in better ACF curing and stronger adhesion. After ageing, the adhesion strength increased for the samples bonded at lower temperatures and decreased for the samples bonded at higher temperatures. ACF assemblies with higher degrees of curing showed smaller increases in contact resistance after ageing. Conduction gaps at the bump‐particle and/or particle‐pad interfaces were found with the help of scanning electron microscopy and are thought to be the root cause of the increase in contact resistance.

The present study focuses on the effect of bonding temperatures on the curing of ACFs, and their adhesion strength and electrical performances after high temperature ageing. The results of this study may help the development of ACFs with higher heat resistance, so that ACFs can be considered as an alternative to lead‐free solders.

This paper aims to investigate the strength at interlayer of specimens fabricated using Contour Crafting (CC) to develop a concrete mixture for large-scale three-dimensional printing.

The collected data from several experiments were analyzed to understand significant factors and their interactions. After developing the empirical model, condition for maximum desirability was identified and the model was validated.

The experimental investigation of varied combination of concrete components introduced an empirical model which can predict the strength at interface. Moreover, an optimized mixture within constrains of the CC nozzle was developed and validated.

Several experimental samples were tested, and the derived empirical model was validated after more than 600 h of work.

Personal and portable electronic devices are becoming an important part of the everyday lives. Electronics miniaturization has been and continues to be the most important driver in this development. The current level of miniaturization has made the use of solder joints challenging and new methods, such as adhesive attachments, have been developed. The applicability of these methods depends crucially on their long‐term reliability. Typical failures mechanisms in adhesive connection include cracking, open joints and delamination. Moisture is the principal cause of failures in adhesive attachments. The purpose of this paper is to examine the long‐term effects of moisture and extended temperature on non‐conductive adhesive (NCA) attachments.

Moisture and extended temperature on NCA attachments are examined by strength tests and by finite element models.

The increase in temperature and moisture induces stresses on the interface of the adhesive and the chip. In the experiments, it is found that the adhesion strength of the adhesive decreased as a function of the time for which the samples are in a humid environment. Failures due to delamination are seen to be the result of these two mechanisms.

Reduction of pitch causes manufacturing problems in direct solder attachments. This paper examines a promising technique to overcome this problem by using adhesive attachment. Instead of solder joints in flip chip attachment, the chips can be attached to the substrate, or components can be attached to a printed wiring board, with adhesives.