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The subject of the quantitative measurement of solderability of electronic components is introduced. The wetting balance in various configurations and modes of operation is being used as the focal point to establish a quantitative measurement capability for solderability of conventional leaded components, surface mounting components and printed circuit interconnections. The principles of operation of the wetting balance and the factors that influence the measurement are discussed. This paper is the first of a series that will cover the development of traceable reference standards for wetting balance calibration, the influence of instrumental design on the measurement, the standardisation of the measurement procedures, the choice and evaluation of a solderability index for the dynamic measurement, and the traceability of the measurement to international standards.

This paper outlines some techniques developed at GEC Research Laboratories to extend the range of specimen types which may be solderability tested by the wetting balance method. Particular emphasis is placed upon surface mounting components and substrates, which have not proved amenable to quantitative testing by conventional means.

This article aims to consider the use of high pressure processing in order to gain functional advantages through proteins structure control. High pressure processing has been used to produce high-quality food with extended shelf life and could also be used to modify foods functionality.

The effect of high pressure on protein structure and functionality is looked at and comparisons are made with heat effect in places. β-lactoglobulin and whey proteins are mainly taken as examples.

A controlled partial protein unfolding through mild high pressure processing could lead to a range of intermediate molecular structures. These are distinct from the native and completely unfolded structure and have been referred to as molten globules. The partly unfolded molecular states, hence, are postulated to have increased functionality and could be interesting for the food industry.

The opportunity and challenges represented by these theoretical elements are discussed. In particular, the effect of protein concentration and aggregation is emphasised.

A combination of a highly efficient thermal insulation, stainless steel foil, and PTFE film resulted in an insulation system which would protect the underside of the wing of the British/French Concorde SST from the heat of its engines. Noise level, engine fire conditions, and penetration by globules of molten titanium were factors which had to be considered in this application.

The paper provides a brief survey of the various aspects of soft soldering, in as far as they are relevant to the manufacture of soldered printed boards. The intention is that only a few lines will be devoted to each subject. It is mainly intended for those who only indirectly enter into contact with soldering, and who want a quick introduction to this field. Next, it may be of interest to those who occupy themselves in depth with soldering, because most aspects come under discussion, if only briefly. Soldering experts are not likely to find anything new, but they may still appreciate the overall survey provided here.

Many of the common defects observed when using solder creams can be related to the materials, formulation and blending of the product. Despite the fact that they have been used for the last 15–20 years some of the most serious of these problems remain. A correlation between material parameters and defects is presented. The three most serious defects are identified as Voids, Solder Balls and Residue and Cleanability and the mechanism and occurrence of these are discussed extensively. Suggestions are presented as to material and process improvements to reduce or eliminate the problem areas. Finally the suggested improvements are tabulated to indicate the effects on all the defects originally identified.

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

Ti_49.4Ni_50.6 (at. %) shape memory alloy (SMA) is a unique class of smart materials because of unbeatable property which given a wide variety of their applications across a broad range of fields including an orthopedic implant. It plays a very important role in the constructions of novel orthopedic implants application (like dynamic compression plate) because of lower Young’s modulus compared to other biomedical implant materials, high mechanical strength, excellent corrosion resistance and unique property like shape memory effect. Conventional machining of Ti-Ni yields poor surface finish and low dimensional accuracy of the machined components. Hence, wire electro-discharge machining (WDEM) of Ti-Ni has been performed. The purpose of this paper is to investigate the effect of variation of five process parameters, namely, a pulse-on time, pulse-off time, spark gap set voltage (SV), wire feed and wire tension on the material removal rate, surface roughness (SR), kerf width (KW) and dimensional deviation (DD), in the WDEM of Ti_49.5Ni_50.6 SMA.

The effect of machining parameters on Ti_49.4Ni_50.6 has been fully explored using WEDM with zinc coated brass wire as an electrode. In this work, L18 orthogonal array based on Taguchi method has been used to conduct a series of experiments and statically evaluate the experimental data by the use of the method of analysis of variance. Scanning electron microscope images of the machined surface, at the highest and lowest pulse-on time, have been taken to evaluate the quality of surface in terms of their SR values.

For the highest pulse-on time, it is observed that blow holes, cracks, melted droplets and craters have been formed on the machined surface with an SR of 2.744 µm, while for the lowest pulse-on time, these are not formed with an SR of 0.862 µm. It is seen that the pulse-on time is the most significant process parameter for MRR, SR and KW, while the DD is significantly affected by spark gap SV. The optimal values of the process parameters have been obtained by the method of analysis of mean and the confirmatory experiments have been carried out to validate results of optimization. Energy dispersive spectroscopy analysis of the machined surface of Ti_49.4Ni_50.6 has shown a certain amount of deposition of material on the machined surface.

This is an original paper.

Programming a multi‐axis robotic device to follow complex contours can be difficult and time consuming. A United States University working with the automotive division of a US company has evolved a prototype system utilising a capacitive displacement transducer.

Brief Particulars of Recently Introduced Materials likely to have Aircraft, Missile or Space Vehicle Applications. Wall Colmonoy (Canada) Ltd. have announced the introduction of four new filler metals in their Nicrobraz series of nickel‐base brazing alloys. The new grades result from continued research to find better ways of meeting the requirements of brazing high temperature metals and special alloys. Nicrobraz 135 meets AMS. 4779 specification, has similar applications to Nicrobraz 160 and is best used where greater joint ductility or machinability is required. Nicrobraz 200 has very high creep and stress rupture strength and is recommended for hot sections of jet and gas turbine engines, and similar components where hardenable base metals are used. Nicrobraz 220 and 230 are both ductile, low penetration filler metals and can be used for cryogenic temperatures to 650 and 820 deg. C. respectively. Recommended uses for the these grades include rocket engine thrust chambers, complex and high temperature heat exchangers.