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The paper aims to use aluminium alloy to substitute steel as the main material of ultra-precision hydro-static bearing system for an ultra-precision plastic electronics production system to lower the manufacturing cost. The total cost of diamond turning and nickel-based electroless coating of an aluminium alloy bearing is expected to be less than the cost of manufacturing a stainless steel bearing.

The paper used a large amount of theoretical calculation to obtain optimal specifications of the bearing system. ANSYS modelling was selected to simulate the deflection of the bearing shaft under high oil pressure. Hundreds of measurements were conducted after the bearing had been manufactured.

The paper provides industrial application insights on using aluminium alloy with a high-quality nickle-based electroless coating as a successful substitution of stainless steel. This created a more economic hydro-static bearing system.

Because of the time limit, different rotational speed tests shall be conducted in the future.

The paper provides implications for the application of nickel-based electroless coating to improve the surface property and bending strength of aluminium alloy, as well as classifying ultra-precision diamond turning as an economic finishing process.

This paper has identified the importance of aluminium alloy with a nickel-based electroless coating as the substitution of stainless steel in a precision hydro-static bearing system.

THE Glacier Metal Co Ltd manufacturers three dry bearing materials, namely Glacier DU, DQ and Deva Metal.

Metallic finishing of materials, unlike non‐metallic finishing, comprises various popular surface modification processes, e.g. electroplating, conversion coating, anodizing, metal spraying, hot dip coating and also diffusion coatings. Diffusion coatings on metallic substrates are well known for their better abrasion resistance and adhesion to the substrate. Resistance to corrosion may also be incorporated on these surfaces by the addition of appropriate dopant elements like Cr, Ni and Al. However, these diffusion alloy‐layers are more sought after for functional properties than their aesthetic look. It appears that the concept of functional metal finishing is gaining ground for its longer service‐life and better performance. Discusses some of these aspects of diffusion alloy coatings on mild steel substrate and analyses their comparative merits and demerits. In this connection, three distinctly different types of barrier layers, namely, hard diffusion alloy layer, e.g. chromiding, Ni‐Cr diffusion coatings and soft‐diffusion layer, e.g. Pb‐Cd, Zn‐Sn barriers and those in between, e.g. hot dip zinc‐alloy coated barrier layers, have been highlighted for their corrosion resistance properties.

Every metal has a range of environmental conditions against which it is resistant or sufficiently resistant as to make the metal economically feasible. Unfortunately it is almost a rule of thumb that the more expensive the metal the smaller the range. In most cases the resistance of the metal is a function of the metal thickness, but the function is such that relatively thin metals can produce very long lives.

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.

Diffusion treatments may comprise the diffusion of interstitial elements such as oxygen, nitrogen, carbon, or boron into the surface from a gaseous or molten salt bath environment, or less commonly it may consist of substitutional diffusion of a previously deposited metal coating or by packing in materials such as ferromanganese or chromium with suitable additives.

Background An increasing number of requests from the engineering industry are being received by the author's company to advise on procedures for modern anti‐corrosive treatment and protection of valves, pumps, compressors, heat exchangers, filters etc.

The properties and constituents of PTF inks are outlined. Surface resistivity in relation to PTF inks is defined. Applications of PTF inks are discussed with emphasis on potential design and cost benefits for SMT applications, including crossovers, polymer multilayer, printing through holes, printed resistors, carbon key pads, moulded and three‐dimensional circuits.

This paper aims to coat ternary composite NiBP-graphite films by Dynamic Chemical Plating “DCP” technique with a growth rate of at least 5 μm/h, which makes this technique a worthy candidate for production of composite films. Electroless nickel plating method can be used to deposit nickel–phosphorous and nickel–boron coatings on metals or plastic surface. However, restrictions such as toxicity, short lifetime of the plating-bath and limited plating rate have limited applications of conventional electroless processes.

DCP is an alternative for producing metallic deposits on non-conductive materials and can be considered as a modified electroless coating process. Using a double-nozzle gun, two different solutions containing the precursors are sprayed simultaneously and separately onto the surface. With this technique, NiBP-graphite films are fabricated and their corrosion and tribological properties are investigated.

With a film thickness of 2 μm, tribological analysis confirms that these coatings have favorable anti-friction and anti-wear properties. Corrosion resistance of NiBP-graphite composite films was investigated, and it was found that graphite incorporation significantly enhances corrosion resistance of NiBP films.

DCP is faster and simpler to perform compared to other electroless deposition techniques. Using a double-nozzle gun, metal salt solution and reducing agents are sprayed to the surface, forming a deposit. Previously, coatings such as Cu, Cu-graphite, Cu-PTFE, Ni-B-TiO2, Ni-P, Ni-B-P and Ni-B-Zn with favorable compactness and adherence by DCP were reported. In this paper, the authors report the application of the DCP technique for depositing NiBP-PTFE nanocomposite films.