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This paper seeks to evaluate the influence of tellurium content on the machinability of the microalloyed pearlitic steel (DIN 38MnS6). Two grades of steels were used, one with high (27 times greater) tellurium content and one with a low tellurium content. Machinability of the steel was determined by the number of holes drilled by the tool before undergoing severe deformation. The drilling test matrix was prepared using a fractional factorial design with five input variables studied at two levels (25‐1). Other variables investigated include cutting speed (45 and 60 m/min), feed rate (0.15 and 0.25 mm/rev), geometry of the twist drills and use of minimum quantity lubrication (MQL) at the flow rates of 30 and 100 ml/h. Statistical analysis of the results revealed that composition of the work material was most influential on tool performance. Addition of tellurium to the steel significantly improved machinability, increasing the number of drilled holes by over 100 per cent. The MQL flow rate was the least influential as increase in the flow from 30 to 100 ml/h reduced drill life only by about 9 per cent.

The drilling tests were carried out in the vertical position, up‐down, without pre‐holes (full drilling). Cutting speeds of 45 and 60 m/min and feed rates of 0.15 and 0.25 mm/rev were employed. Drills with two sharpening types were tested. Cutting fluid used was vegetable based and applied using the MQL technique at flow rates of 30 and 100 ml/h. The rejection criterion adopted was severe deformation of the drills and the number of machined holes was used to measure the machinability of the material.

Of all the variables investigated in this study, the least influential on drill performance is the MQL flow rate. Increase in the flow rate from 30 to 100 ml/h reduced drill performance by 9 per cent, contrary to expectation. This is a result of the cooling‐lubricant action balance promoted by the cutting fluid applied in low quantities (MQL). The most influential variable on drill performance is addition of Te to the work material which gave over twofold (103 per cent) improvement in drill performance at the cutting conditions investigated. The Te particles act at the chip‐tool interface, reducing the work necessary to shear the material during chip formation. Increase in both the cutting speed and the feed rate both lowered drill performance during machining due to associated increase in cutting temperature which tended to accelerate thermally related wear mechanisms.

This work was conducted to evaluate the machinability of a novel alloyed steel employed in the automobile industry. Drilling was considered as most automobile components especially the engine block is designed with many holes which require drilling process.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

Although the literature on Lean Six Sigma (LSS) implementation has evolved, a deeper understanding of the LSS practices applied in organisations in developing countries is needed. This paper aims to analyse LSS in a manufacturing company in the context of LSS implementation in an emerging economy.

This paper uses case-based research. Data collected in a large manufacturing company through multiple sources of evidence were triangulated to derive the findings. This paper analyses aspects related to the implementation of both programmes and their synergy, as well as some critical and failure factors.

The main results show that Lean and Six Sigma are applied separately in two different programmes. Some aspects that are necessary to increase the integration of both approaches were identified while considering each phase of the DMAIC and the current approach applied by the company. Although some positive results have been achieved, there are many critical and failure factors that may influence the implementation of both approaches, such as employee training and changes in the organisational environment. Finally, the comprehensive integration of both approaches needs to be undertaken by the company.

The findings from this single case study cannot be generalised.

This paper may be used as a guiding reference for managers and consultants to help them when working towards more successful LSS implementation.

First, this paper investigates LSS in a manufacturing firm located in a developing country; this issue is still seldom addressed in the literature. Second, it may contribute to practitioners’ knowledge by delivering insights into a real context, as well as the relevant issues to be addressed when implementing LSS in similar contexts.