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THE missile and power‐plant designers of today are continually in need of materials to withstand higher loads and higher operating temperatures. The development of the high‐speed guided missile is dependent on the output of the materials laboratory for new materials of superior properties and new methods of fabrication. The materials engineer has thus far been able to keep abreast of the demands for better materials. Several new materials, all developed for elevated temperature operation, are at present available in some state of experiment or production for consideration in the design of advanced performance missiles and power‐plants.

The purpose of this paper is to evaluate relationships between workaholism and satisfaction outcomes with job, career and life overall among managerial and professional women and explore the moderating role of social support in these associations.

Self-report measures collected online from 350 alumnae from top-ranked business schools currently in the US labor force were analyzed through hierarchical multiple regression analyses.

Workaholism components explained significant amounts of variance in job, career and life satisfaction. Specifically, lower levels of work enjoyment were consistently associated with detrimental outcomes and high drive impacted both job and life satisfaction negatively. Social support moderated the relationship between job satisfaction and workaholism through work enjoyment, with women with greater social support demonstrating higher job satisfaction at equivalent work enjoyment levels versus those with low social support.

This paper shares methodological weaknesses involving the nature of the sample and self-report methods of measurement common to workaholism research.

In the context of today’s competitive workplaces, results provide a cautionary message of the harmful effects of workaholic dispositions for a certain segment of professional women. It emphasizes the importance of work enjoyment and positive intrinsic motivation, while suggesting that job designs that reflect the work involvement predispositions of each woman can be beneficial.

This paper extends the understanding of workaholism correlates to female MBA graduates from top management schools in the USA and investigates, for the first time, the role of social support in those relationships.

Food insecurity in the Latin American region has become a complex problem that significantly impacts people's physical and mental well-being. The factors causing food insecurity are varied, ranging from social, political, and economic causes. Ensuring access to food is not a task with limited responsibilities; on the contrary, both public and private institutions must contribute to creating sustainable and innovative solutions. In general, it is necessary to ensure that the food system flows correctly, ensuring the availability of balanced and nutritious food for the diet of the inhabitants of a given nation. Alternative solutions apart from the government's help include sustainable cultivation, finger millet, and close cooperation with the farmers from the agriculture sector. The present research aims to consolidate theoretical information on the Latin American situation and seek the leading solutions of the parties involved.

Erosion and abrasion are the prominent wear mechanisms reducing the lifetime of machine components. Both wear mechanisms are playing a role meanwhile, generating a synergy, leading to a material removal on the target. The purpose of study is to create a mathematical expression for erosive abrasive wear.

Many factors such as environmental cases and material character have an influence in erosive abrasive wear. In the work, changes in abrasive size and material hardness have been analyzed. As an abrasive particle, quartz sand has been used. All tests have been done in 20 wt.% slurry. Heat treatment has been applied to different steel specimens (steel grades C15, St 37 and Ck45) to change hardness value, which ranged from 185 to 880 Vickers hardness number.

After the four-hour test, it is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. Worn surfaces of the targets have been examined to figure out the wear mechanisms at different conditions under scanning electron microscopy. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease. The diameters of micro-craters have been about 3–8 µm in hard materials and about 120–140 µm in soft materials.

It is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease.

The study enables to indicate the dominant factor in worn steel used in mechanical components.

After analyzing the test results, a novel mathematical expression, considering both abrasive size and material hardness, has been developed.

Plasma spray coating technologies are capable of depositing a wide range of compositions without significantly heating the substrate. The objective is to characterise plasma sprayed metallic coatings on a Fe‐based superalloy.

NiCrAlY, Ni‐20Cr, Ni3Al and Stellite‐6 metallic coatings were deposited on a Fe‐based superalloy (32Ni‐21Cr‐0.3Al‐0.3Ti‐1.5Mn‐1.0Si‐0.1C‐Bal Fe) by the shrouded plasma spray process. The coatings were characterised in relation to coating thickness, porosity, microhardness and microstructure. The high temperature oxidation behaviour of the coatings was investigated in brief. The techniques used in the present investigation include metallography, XRD and SEM/EDAX.

All the coatings exhibited a lamellar structure with distinctive boundaries along with the presence of some porosity and oxide inclusions. The microhardness of the coatings was observed to vary with the distance from the coating‐substrate interface. The St‐6 coating had the maximum microhardness, whereas the lowest hardness was exhibited by the Ni3Al coating. The phases revealed by XRD of the coatings confirmed the formation of solid solutions, whereas EDAX analysis of the as‐sprayed coatings confirmed the presence of basic elements of the coating powders. So far as high temperature oxidation behaviour is concerned, all of the coatings followed the parabolic rate law and resulted in the formation of protective oxide scales on the substrate superalloy.

The plasma spray process provides the possibility of developing coatings of Ni3Al as well as commercial available NiCrAlY, Ni‐20Cr and St‐6 powders on Fe‐based superalloy Superfer 800H

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

The basis and the extent of theoretical induced velocity calculations are reviewed. The theory is then applied to interference problems involving additional rotors, wings, and tails in the flow. For such cases, the interference effects can be calculated with acceptable accuracy. For hovering, superposition is used to introduce ground effect into the calculations. The resulting flow field offers a qualitative explanation of several previously observed phenomena. It is shown that, because of assumptions inherent in the analysis, the present induced‐flow theory cannot be used to predict the detailed aerodynamic loading on the rotor blades.

Present day aircraft and engines impose conditions which necessitates their structures to be manufactured from ultra high‐strength thermal‐resistant alloys. Future aircraft will need more and more components of such alloys, many of which are new to the industry. Little information on machining techniques for production operations is at present available and it is for this reason that Air Material Command has sponsored a research programme to study the problem.

Stainless steel 316 was coated with CeO₂ and Y₂O₃ modified aluminide and titanium aluminide coatings. The coatings were prepared by the pack cementation method and the high temperature oxidation behaviour of the coatings was investigated in an atmosphere containing a limited supply of air. The performance of the coatings was studied by measuring oxidation kinetics, and by scanning electron microscopic techniques. The oxidation rates of these coatings were reduced in the presence of CeO₂ and Y₂O₃ due to better adherence of their oxide scales.