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This study aims to improve the market competitiveness of iron and steel manufacturers in developing countries by reducing their production costs.

The research methodology relies on a case study-based approach. The study relies on six steps. The first is the preparation, then the five steps of the six-sigma – define, measure, analyze, improve, control. The qualitative and quantitative data were considered. The qualitative analysis relies on the experts’ judgment of internal status. The quantitative analysis uses the job floor data from three iron and steel manufacturers. After collecting, screening and analyzing the data, the root causes of the different wastes were identified that increase production costs. Consequently, lean manufacturing principles and tools are identified and prioritized using the decision-making trial and evaluation laboratory method, and then implemented to reduce the different types of waste.

The main wastes are related to inventory, time, quality and workforce. The lean tools were proposed with the implementation plan for the discovered root causes. The performance was monitored during and after the implementation of the lean initiatives in one of the three companies. The obtained results showed an increase in some performance indicators such as throughput (70.6%), revenue from by-products (459%), inventory turnover (54%), operation availability (45%), and plant availability (41%). On the other hand, results showed a decrease of time delay (78%), man-hour/ton (52.4%) and downgraded products (63.3%).

The current case study findings can be utilized by Iron and Steel factories at the developing countries. In addition, the proposed lean implementation methodology can be adopted for any other industries.

The current work introduces an original and practical road map to implement the lean six-sigma body of knowledge in the iron and steel manufacturers.

This work introduces an effective and practical case study-based approach to implementing the lean six-sigma body of knowledge in the iron and steel manufacturers in one of the underdevelopment countries. The consideration of the opinion of the different engineers from different sectors shows significant identification of the major problems in the manufacturing and utility sectors that lead to significant performance improvement after solving them.

Identification of the critical process conditions that enhance Cu diffusion in ferrite grain boundaries and promote precipitation of Cu-rich particles in the proximity of steel semi-finished products surface is crucial for every steel maker as it leads to the creation of hot shortness cracks in final products deteriorating surface condition. The purpose of this paper is to reveal the possible effect of Cu segregation in the metal/oxide interface, its role in surface crack initiation and, finally, to propose actions to prevent from hot shortness issues throughout the production chain of steel products.

The here presented study was based on S355 steel plate production starting from re-melting of scrap in an EAF, followed by metallurgical treatment in a Ladle Furnace, continuous casting, re-heating (RH) and thermo-mechanical rolling in a reversing mill. For the purposes of this study, more than ten heats, 100 t of steel each, were analyzed. Here presented are depicted steels in the high and low end of the permitted Cu-wt-% spectrum, 0.4 wt-% Cu (0.15 wt-% C, 1.1 wt-% Mn, VTi micro-alloyed steel) and 0.25 wt-% Cu (0.09 wt-% C, 1.2 wt-% Mn, NbTi micro alloyed steel), respectively.

Although Cu levels of 0.25-0.40 wt-% are well below the Cu solubility in austenite and ferrite (8 percent wt-% and 3 wt-% Cu, respectively) and within specifications, precipitation of Cu-rich particles is observed in industrial semi-finished and/or final products. Cu-rich precipitates and Cu segregation along grain boundaries near the steel surface lead to hot shortness cracks in industrial products.

Hot shortness surface defects related to Cu presence in steel having significantly lower Cu amounts than its maximum solubility in austenite and ferrite does not make sense in first place. Correctly, Cu is expected to remain in solid solution. Identification of Cu-rich particles is explained on the basis of the development of double diffusion actions: interstitial diffusion of carbon (decarburization) and substitution diffusion of copper. Root cause analysis and reliable countermeasures will save financial and material resources during steel production.

Automobile scrap re-melting results in noticeable Cu amounts in EAF produced steel. Presence of Cu-rich particles in grain boundaries near the surface of intermediate or final products deteriorates surface quality through relevant surface defects. Identification of Cu-rich particles is explained on the basis of the development of double diffusion actions: interstitial diffusion of carbon and substitution diffusion of copper. Pre condition for metallic Cu precipitation in ferrite is the Cu amount to be above 3 wt-%, which is ten times higher than the usual permitted Cu amount in such steel grades. This pre-condition is met through austenite oxidation during RH.

The purpose of this paper is to identify the influencing factors which cause casting defects and determination of optimum value of factors to minimize these defects in a melt shop industry, situated in north India. Percentage contribution of these factors is also estimated to develop an empirical expression between process performance and independent input variables.

Optimization technique for melt shop process parameters of a cast iron differential housing cover based on the Taguchi method is proposed. The focus of this paper is on the robustness of the sand casting process and the case study is based upon a leading automobile foundry industry, located in north India. Taguchi's experimental design and regression analysis techniques are used to optimize the control factors, resulting in improvement of the product quality and stability. The various confirmation tests are also carried out in the range of process parameters.

The outcome of this case study is to optimize the process parameters of the melt shop process, which leads to minimizing the casting defects. The process parameters considered are: mild steel, pig iron, cast iron, ferrosilicon, lime stone, ferromanganese, cock and ferrochrome. Best proportions of charge constituents that are contributing to casting defects in melt shop are identified in the first stage. These identified factors are analyzed using “Design of Experiments” approach in the second stage. ANOVA analysis is also performed for robust design of factor values and an appropriate empirical model is formulated.

A lot of effort has been put into developing the appropriate empirical model for the automobile foundry industry but additional work may also be done for gating design of the casting industry.

The paper shows that the process parameters of any casting industry can be optimized and casting defects in the melt shop can be identified in the first stage.

The research findings could be applied to various manufacturing industries, especially the casting industries.

The purpose of this paper is to investigate the influence of fluor‐oligomeric coat on the mechanical properties of steel surface, as well as the chemical interaction of fluor‐oligomeric films with surface and theoretical‐phenomenological interpretation of structural processes in friction surface.

Four groups of specimens were studied: two groups of specimens without any wear tests – initial steel specimen as control version and a specimen which was ten times coated by fluor‐oligomer, and two groups of specimens, which were tribologically tested for one million cycles – without any coating and coated specimens. Closed kinematical profile scheme roller‐roller of steel 45 was chosen for tribological tests. Wear of friction surface after those tests was investigated. The interaction between fluor‐oligomer and iron was studied by means of Mössbauer spectroscopy. The micro‐hardness of matrix was also measured.

Affecting the surface of steel by the fluor‐oligomer and friction produces the complicated processes of carbide decay and formation occur. The mechanisms are found which are related to the weakening of chemical bond in steel during the absorption, to the generation of microscopic ruptures, to the decrease (30‐50 per cent) of the amount of carbides and its increase during the friction (up to 50 per cent). The mechanical effect which causes the regeneration of carbides during friction is revealed. Tribological efficiency of fluor‐oligomeric coats (five times lower wear of coated specimens) is explained by the balance of three processes – the softening of matrix during adsorption, the detention of dislocations, and formation of hard particles in the matrix.

The complex mechanism of the increase of wear resistance is explained by filling of ductile matrix with carbide particles.

High-silicon chromium iron (HSCI) has been used in ground grids in southern China, while there was a lack of study on its corrosion behavior in this soil environment. The purpose of this paper is to discover the corrosion of HSCI in acidic and alkaline soil solutions.

The original defects on the HSCI surface were observed using optical microscopy, and the corrosion behavior of the HSCI in the acidic and alkaline soil solutions were jointly detected using electrochemical measurements and scanning electron microscopy/energy dispersive spectrometer.

The results showed the corrosion rates of the HSCI in the acidic and alkaline soil solutions were limited, and the high contents of Cr and Si in matrix was responsible for its high corrosion resistance. The HSCI showed a similar corrosion tendency in the two solutions, while its corrosion rate in the acid soil solution was higher than that in the alkaline soil solution. The corrosion pits on the specimen surface were originated from the original defects in matrix, and the edges of the corrosion pits were more rounded than the original defects after 720 h immersion in the two solutions. The original defects in the HSCI matrix played a significant role in the corrosion process.

The paper discovered the corrosion evolution of HSCI in the acidic and alkaline soil solutions. What is more, the acceleration role of the original defects on the corrosion of the HSCI in the acidic and alkaline soil solutions was discovered in the paper. The results are beneficial for the material selection of ground grid equipment in engineering.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Index by subjects, compiled by K.G.B. Bakewell covering the following journals: Facilities Volumes 8‐17; Journal of Property Investment & Finance Volumes 8‐17; Property Management Volumes 8‐17; Structural Survey Volumes 8‐17.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐17; Journal of Property Investment & Finance Volumes 8‐17; Property Management Volumes 8‐17; Structural Survey Volumes 8‐17.

Index by subjects, compiled by K.G.B. Bakewell covering the following journals: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.