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THE following notes are being written solely for the benefit of ground engineers who are endeavouring to acquire the necessary knowledge to obtain a D licence. A licence in Category D demands a knowledge of the heat treatment of steels. Practical experience is, of course, quite as essential in this as in other and allied branches of engineering, but a theoretical study of the reasons for, and the results of, different heat treatment, is equally essential for a complete understanding of the subject.

The purpose of this study was to compare the electrodeposition behavior and corrosion resistance of ternary and binary alloys.

Potentiodynamic polarization resistance measurement and anodic linear sweep voltammetry techniques were used for the corrosion study. The surface morphology and chemical composition of the deposits were examined using scanning electron microscopy and atomic absorption spectroscopy, respectively. The phase structure was characterized by X-ray diffraction analysis. Electrodeposition behavior was carried out using cyclic voltammetry and galvanostatic techniques.

It was found that the obtained ternary alloy exhibited better corrosion resistance and a more-preferred surface appearance compared to the binary alloys that were electrodeposited under similar conditions.

The ternary alloy showed better anticorrosion properties compared to binary deposits that were electroplated successfully from the plating baths. The Zn-Co-Fe alloy could be used advantageously in industry because the ternary alloy exhibits the collective properties of the binary alloys in one alloy via the electrodeposition of Zn-Ni-Co alloy.

Increasing the corrosion resistance implies to social economic increases.

To date, the electrodeposition of Zn-Co-Fe alloy was studied in only a small number of articles. It was found that the presence of Co or Fe could provide a useful coating on the steel that would reduce its susceptibility to corrosion attack.

This paper aims to investigate the processability by selective laser melting (SLM) of materials of potential interest for innovative biodegradable implants, pure Fe and pure Zn. The processability of these materials is evaluated with a more established counterpart in permanent implants, stainless steel. In particular, the processing conditions were studied to reduce porosity due to incomplete fusion of the powder.

In the first phase of the experiments, SLM of AISI 316L was studied through design of experiments method. The study was used to identify the significant parameters in the experimental range and estimate the fluence ranges for pure Fe and pure Zn using the lumped heat capacity model. In the second phase, SLM of pure Fe and pure Zn were studied using estimated fluence ranges. In the final phase, best conditions were characterized for mechanical properties.

The results showed that complete melting of AISI 316L and pure Fe could be readily achieved, whereas laser melting generated a foam-like porous structure in Zn samples. The mechanical properties of laser melt implant materials were compared to as-cast and rolled counterparts. Laser melted AISI 316L showed superior mechanical performance compared to as-cast and rolled material, whereas Fe showed mechanical performance similar to rolled mild steel. Despite 12 per cent apparent porosity, laser melted Zn exhibited superior mechanical properties compared to as-cast and wrought material because of reduced grain size.

The paper provides key processing knowledge on the SLM processability of new biodegradable metals, namely, pure Fe, which has been studied sparingly, and pure Zn, on which no previous work is available. The results prefigure the production of new biodegradable metallic implants with superior mechanical properties compared to their polymeric counterparts and with improved degradation rates compared to magnesium alloys, the reference material for biodegradable metals.

IN this article it is proposed to deal with that wide range of aircraft material which is grouped under the heading of metallic materials. Ground Engineers of all categories should possess a sound knowledge of the material which they handle, and this knowledge is a definite requirement for a Gound Engineer's licence in Categories “B” and “D.” The impossibility of an exhaustive treatment of this subject in an article of this nature must be appreciated, and little can be done but to direct attention to the more salient points. Readers are reminded that many excellent text‐books dealing with Metallurgy are to be obtained and that a study of such books will be found both interesting and profitable.

Organic compounds containing sulphur, nitrogen and oxygen atoms are capable of retarding metallic corrosion. As the thiourea molecule contains one sulphur and two nitrogen atoms, thiourea and its derivatives are potential corrosion inhibitors. While extensive investigations have been carried out on inhibitor properties of thiourea, due attention has not yet been paid to a systematic study of inhibitor action of thiourea derivatives. However, several substituted thioureas have been investigated as corrosion inhibitors. The applications of thiourea and its derivatives as corrosion inhibitors reported in literature up to 1967 are narrated in this article.

GERMANY ‘Phenol’ corrosion of telephone cables. The lead coats of telephone cables are often protected by bituminised paper strips and jute cloth. This does not provide any protection against corrosion. The cables corrode very easily and they usually seem to succumb to the so‐called ‘phenol’ corrosion. As it was not possible to reproduce ‘phenol’ corrosion in the laboratory, it was assumed that effect might be caused by jute.

Due to the increasing awareness of the need to protect the environment, reverse logistics (RL) is being promoted to improve the ecological sustainability of production. RL can lower the costs of waste disposal, increase market competitiveness, and maintain a good corporate image. Hence, modern companies are focusing on environmental protection to demonstrate social responsibility. According to the OECD report of 2003, buildings consume 32 percent of resources, 12 percent of water, and 40 percent of energy worldwide, and the building waste comprises almost 40 percent of the all waste in the world. Therefore, controlling waste from the interior design sector may help slow global warming. This paper aims to discuss these issues.

This investigation models the current and new RL of disposing interior design waste in Taiwan. Modeling the carbon footprint (CF) of disposing interior design waste can help companies be aware of the environmental impact of disposing of waste, and how to improve it through RL. This investigation models the CFs of disposing interior design waste based on studies from Benjaafar et al. (2013), Pishvaee et al. (2009, 2010), and Tascione et al. (2014).

Analytical results showed that the RL significantly decreases the environmental impact of wastes. Companies can control carbon emission through the findings of this study and find how to improve their recycling process through RL.

This study used the model proposed by Tascione et al. (2014) to develop an RL model for Taiwan. Whereas most studies in the literature analyze the carbon emissions from the comparison between cost and benefit, this study considered the logistics for the whole lifecycle of a product. The analytical results of this study reveal that that RL can reduce the environmental impact of wastes. This case study is the first to obtain results that can be extended to other countries. This study also reveals the importance of recycling plants that can process demolition waste for reuse.

This is the first study to model the RL based on literatures. The findings of this study can be extended to other cases.

After going through the worst of the periodic post‐war depressions, prospects for the British steel industry at last begin to gleam, with current output showing a marked improvement on last year's figures. But optimism is clouded by friction between the Government and BSC over price levels—regarded by the Corporation as still too low—and scale of future development. Report by Roger Eglin of the Observer.

The dissolution rates of iron and alloyed steels in molten lead‐free solders were investigated in order to clarify the effect of erosion of iron plating on soldering iron tips. The dissolution rates of iron‐based alloys in lead‐free solders were found to be about three times greater than in conventional Sn‐Pb eutectics, indicating that the iron plating of a soldering iron tip is subjected to heavier damage when used with lead‐free rather than eutectic Sn‐Pb. Several steel alloys showed dissolution rates similar to that of pure iron, suggesting that compositional changes in the iron plating may have little influence on the erosion depth. Decreases in the reaction temperature and time, and a small addition of iron into the solder was found to be effective in suppressing both dissolution of iron wire and erosion of iron plating.

The work described in this paper is part of a current programme that has two objects: (1) to investigate further the reasons for the different scaling behaviour of steel in steam and carbon dioxide, although these gases have similar oxygen potentials; (2) to provide background information for an investigation into the effect of variations in re‐heating furnace atmospheres upon scaling and scale adhesion.