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The purpose of this study is to look into the hygroscopic and tribo-mechanical properties of a polypropylene/polyamide-6 (PP/PA6) blend and a PP/PA6/Boron sesquioxide composite.

The hygroscopic behaviour of the PP/PA6 blend and PP/PA6/Boron sesquioxide composite was studied using a water contact angle goniometer in this study. To validate the hygroscopic behaviour of the blend and composite, water contact angles and surface energy of the materials were investigated. Tensile strength and hardness tests were used to determine mechanical characteristics, and tribological experiments on a pin-on-disc tribometer were used to demonstrate the friction and wear rates of dry and water-conditioned blends and composites. The melting temperature of dry and water-conditioned composites was determined using DSC analysis.

The hygroscopic effect of the PP/PA6 blend was found to be minimal in the experiment, while it was relatively dominating in the PP/PA6/Boron sesquioxide composite. Tensile strength was found to be somewhat lower in blend and composite compared to virgin PP, whereas hardness was found to be higher in both blend and composite. The composite’s tribological testing findings were fairly outstanding, with the coefficient of friction (COF) and wear rates significantly reduced due to boron sesquioxide reinforcement. The reaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite even further. Following 30 days of water conditioning, the weight of the blend increased by 3.64% and the weight of the composite increased by 6.45% as compared to the dry materials. After water conditioning, tensile strength reduced by 0.8% for the blend and 14.16% for the composite. Hardness was determined to be the same in the dry state and after water-conditioning for blend but dropped 1% for composite. As compared to blend, the COF and wear resistance of composite were 15.52% and 25.16% higher, respectively. After absorbing some water, the results increased to 28.57% and 34.9%, respectively.

The mechanical and thermal behaviour of polymer composites (particularly polyamide composites) vary depending on the surrounding environment. Tests were carried out to explore the effect of water treatment on the tribo-mechanical and thermal characteristics of PP/PA6/Boron sesquioxide composite. Water treatment caused polyamides to bind with water molecules, resulting in voids in the material. The interaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite.

A high-boron concentration solution is commonly used as a buffer system in the study of metal corrosion. However, it is impossible to apply such a high-boron concentration solution in the practical use because of the high-cost and environment problem.

In this study, the authors examined the effect of a low dosage of boric acid and borax mixture as inhibitor to suppress carbon steel corrosion in 1 M HCl solution by weight loss experiment and various electrochemistry methods (potentiodynamic polarization curves, electrochemical impedance spectra and electrochemical noise).

Results showed that the borate mixture exhibited an anodic-type inhibitor characteristic, when the total boron concentration was in the range of 100∼150 mg L⁻¹. The passivation performance derived from the formation of a passive film with and FeBO₃-FeOOH structure, whose integrity and thickness gradually increased with the increasing boron concentration.

Low boron solution could protect carbon steel from the attraction of corrosive ions by forming a passive film with Fe-O-B structure. The findings broaden the application range of borate solution in the industry.

This study aims to evaluate and compare by 100 hours engine bench tests the tribological performances of two types of lubrication oils, which were sulfur-based, boron succinimide-containing antiwear package (NP-3) oil and conventional zinc dialkyldithiophosphate (ZDDP)-containing (R-1) oil.

The tribological performances of the oils were evaluated in three main contexts, including engine tests, physical/chemical changes and surface analysis.

Results showed that NP-3 lubrication oil, which was environment- and catalyst-friendly, can be an alternative lubrication oil with its tribological performance due to similar antiwear characteristics with the ZDDP.

Attempts to develop catalysis- and environment-friendly antiwear additive packages have not presented popular or commonly used ZDDP-free products for the vehicle industry. This study presents tribological characterization of a newly developed ZDDP-free lubricating oil by engine bench tests.

The West European metalworking lubricants market has seen a number of major changes in the past decade.

There are different levels in elaborating a search strategy. The ideal formulation requires good knowledge of the relevant subject area, of the online system being used, and of the relevant files. A number of sample questions in the chemical field are taken up, and it is shown why some questions can be answered only by a skilled online intermediary searcher, whereas other searches can be performed satisfactorily by either the skilled online expert or by the end user.

The following classified, annotated list of titles is intended to provide reference librarians with a current checklist of new reference books, and is designed to supplement the RSR review column, “Recent Reference Books,” by Frances Neel Cheney. “Reference Books in Print” includes all additional books received prior to the inclusion deadline established for this issue. Appearance in this column does not preclude a later review in RSR. Publishers are urged to send a copy of all new reference books directly to RSR as soon as published, for immediate listing in “Reference Books in Print.” Reference books with imprints older than two years will not be included (with the exception of current reprints or older books newly acquired for distribution by another publisher). The column shall also occasionally include library science or other library related publications of other than a reference character.

This paper aims to study the effect of aging and cooling rate on the reliability of the solder joint using electroless nickel boron (EN-Boron) as a surface finish in the electronic packaging area.

EN-Boron was plated on a Cu substrate through electroless plating method. This process was followed by reflow soldering of Sn–3.0Ag–0.5Cu solder alloy on metallized Cu substrate to form a joining. Then, the specimens were cooled using different cooling mediums such as air (slow cooling) with 15.7 °C/min and water (fast cooling) with 110.5 °C/min. After that, the specimens were subjected to isothermal aging at 150°C for 0, 250 and 1,000 h. Finally, they went through a lap shear test following ASTM D1002. Optical microscope and scanning electron microscopy were used for intermetallic compound (IMC) characterization. The type of IMC formed was confirmed by field emission scanning electron microscope-energy-dispersive X-ray spectroscopy (FESEM-EDX).

The results showed that the IMC type changed from the combination of Ni₃Sn4 and (Ni, Cu)₃Sn4 after reflow soldering into fully (Ni, Cu)₃Sn4 when aged for 1,000 h. The formation of (Ni, Cu)₃Sn4 and Cu₃Sn underneath the IMC layer played a role in reducing the shear strength of joining. Overall, water cooling was reported to provide higher shear strength of solder joint compared to air cooling medium.

The shear strength when using EN-Boron as the surface finish is comparable to the surface finish conventionally used.

The purpose of this paper is to investigate how impregnation with boron compounds affects the surface hardness of varnished wood materials.

Test samples were prepared from Scotch pine, Oriental spruce, and Uludag fir, which met the requirements of ASTM D 358.These samples were impregnated with boric acid (Ba) and borax (Bx) using a vacuum technique, according to ASTM D 1413 guidelines. After impregnation, surfaces were coated with cellulosic, synthetic, polyurethane, water‐based, acrylic, and acid‐hardening varnishes in accordance with ASTM D 3023 guidelines. Surface hardnesses of specimens after the varnishing process were determined, in accordance with ASTM D 4366 guidelines.

Surface hardness was greatest for samples of spruce treated with Ba and polyurethane varnish, and lowest for samples of Scotch pine treated with Bx and synthetic varnish. With regard to wood type, impregnation material, and varnish type, surface hardness was greatest for Oriental spruce impregnated with Ba and polyurethane varnish and lowest for Scotch pine impregnated with Ba and synthetic varnish. Thus, impregnation with boron compounds increased the surface hardness of the varnished wood.

A protective coating (such as varnish) has limited resistance to external effects and the lifetime of the coating will be determined by the type and severity of conditions to which it is exposed.

Types of varnishes, wood materials, and impregnation chemicals affect surface hardness and can influence the usefulness of wood materials, where surface hardness values are important.

The study results reported in the paper help address the lack of research in this field and should be informative, in particular, for manufacturers and consumers in the furniture and decoration sector.

The purpose of this study is to prepare a state-of-the-art review on advanced ceramic materials including their fabrication techniques, characteristics, applications and wettability.

This review paper presents the various types of advanced ceramic materials according to their compounding elements, fabrication techniques of advanced ceramic powders as well as their consolidation, their characteristics, applications and wetting properties. Hydrophobic/hydrophilic properties of advanced ceramic materials are described in the paper with their state-of-the-art application areas. Optical properties of fine ceramics with their intrinsic characteristics are also presented within. Special focus is given to the brief description of application-based manipulation of wetting properties of advanced ceramics in the paper.

The study of wetting/hydrophobicity/hydrophilicity of ceramic materials is important by which it can be further modified to achieve the required applications. It also makes some sense that the material should be tested for its wetting properties when it is going to be used in some important applications like biomedical and dental. Also, these advanced ceramics are now often used in the fabrication of filters and membranes to purify liquid/water so the study of wetting characteristics of these materials becomes essential. The optical properties of advanced ceramics are equally making them suitable for many state-of-the-art applications. Dental, medical, imaging and electronics are the few sectors that use advanced ceramics for their optical properties.

This review paper includes various advanced ceramic materials according to their compounding elements, different fabrication techniques of powders and their consolidation, their characteristics, various application area and hydrophobic/hydrophilic properties.

The use of boron compounds or other preservatives of the nature of drugs in cream is alleged to be necessary mainly for two reasons, namely, long distance transit leading to a considerable lapse of time between despatch and consumption, and the uncertainty attaching to the disposal of consignments of perishable and valuable material in a fresh or apparently fresh condition.