Journal of achievements in materials and manufacturing engineering 

About: Journal of achievements in materials and manufacturing engineering is an academic journal published by Index Copernicus International S.A.. The journal publishes majorly in the area(s): Microstructure & Alloy. It has an ISSN identifier of 1734-8412. Over the lifetime, 1941 publications have been published receiving 18132 citations. The journal is also known as: JAMME.

Methods for the calculation of surface free energy of solids

Abstract: Purpose: The main purpose of this paper is the analysis of the most common methods for the calculation of the surface free energy (SFE) of solids, utilising the results of the contact angle measurements. The calculation deals also with the SFE at the interface, especially that at the surface of polymers and polymeric materials. The survey has been meant to ease the understanding of physical processes occurring at the solid-liquid interface and to help to find proper measuring methods with respect to various physical systems. Design/methodology/approach: The presented analysis has been based on the papers of the fundamental nature as well as on the specialised literature reports. The results of the experimental and theoretical studies of the author of this article are also considered. Findings: Different assumptions have been made in the individual methods for calculating the SFE of polymeric materials. Thus, the SFE values for a given material, obtained by various methods and with use of different measuring liquids, are not consistent. The method for the calculation of the SFE of porous or granulated materials, powders, and fibres, in which the Washburn equation is utilised, is very useful in practice. Currently, there is no appropriate alternative to this method. Research limitations/implications: The method for calculating the SFE with use of the equation of state requires further investigation, both experimental and theoretical. Further studies on the phenomena associated with penetration of the measuring liquids into the bulk of an examined material and on the relevant changes concerning this material, including the changes in its SFE, have also to be carried out. Practical implications: The presented results of the investigations may be applied in optimisation of the current and derivation of the new methods for calculating the SFE of solids and liquids, including mainly the SFE of polymers in the solid state. Originality/value: Because of differences in the assumptions made in most of the methods for the SFE calculation and of differences in the interactions between the individual measuring liquids and the examined material, the SFE values for various polymer materials may be compared with one another only when the contact angle measurements have been made using the same measuring liquids and when the SFE calculations have been performed by the same method.

Quality Improvement Methodologies - PDCA Cycle, RADAR Matrix, DMAIC and DFSS

Abstract: Purpose: of this paper is to introduce the reader to the characteristics of PDCA tool and Six Sigma (DMAIC, DFSS) techniques and EFQM Excellence Model (RADAR matrix), which are possible to use for the continuous quality improvement of products, processes and services in organizations. Design/methodology/approach: We compared the main characteristics of the presented methodologies aiming to show the main prerequisites, differences, strengths and limits in their application. Findings: Depending on the purpose every organization will have to find a proper way and a combination of methodologies in its implementation process. The PDCA cycle is a well known fundamental concept of continuous-improvement processes, RADAR matrix provides a structured approach assessing the organizational performance, DMAIC is a systematic, and fact based approach providing framework of results-oriented project management, DFSS is a systematic approach to new products or processes design focusing on prevent activities. Research limitations/implications: This paper provides general information and observations on four presented methodologies. Further research could be done towards more detailed study of characteristics and positive effects of these methodologies. Practical implications: The paper presents condensed presentation of main characteristics, strengths and limitations of presented methodologies. Our findings could be used as solid information for management decisions about the introduction of various quality programmes. Originality/value: We compared four methodologies and showed their main characteristics and differences. We showed that some methodologies are more simple and therefore easily to understand and introduce (e.g. PDCA cycle). On the contrary Six Sigma and EFQM Excellence model are more complex and demanding methodologies and therefore need more time and resources for their proper implementation.

Analyses of surface roughness by turning process using Taguchi method

Abstract: Purpose: The purpose of this research paper is focused on the analysis of optimum cutting conditions to get lowest surface roughness in turning SCM 440 alloy steel by Taguchi method. Design/methodology/approach: Experiment was designed using Taguchi method and 18 experiments were designed by this process and experiments conducted. The results are analyzed using analysis of variance (ANOVA) method. Findings: Taguchi method has shown that the depth of cut has significant role to play in producing lower surface roughness followed by feed. The Cutting speed has lesser role on surface roughness from the tests. Research limitations/implications: The vibrations of the machine tool, tool chattering are the other factors which may contribute poor surface roughness to the results and such factors ignored for analyses. Originality/value: The results obtained by this method will be useful to other researches for similar type of study and may be eye opening for further research on tool vibrations, cutting forces etc.

Silicon nitride ceramics - review of structure, processing and properties

Abstract: Purpose: Purpose of this paper is the applying of new technology in injection moulding technique and investigation of reinforcement of PC as dispersed phase inside PP matrix (Table 1). Second aim of work is enrichment of those composites by nanoclay and analyzing mechanical behaviour of nanocomposites. Design/methodology/approach: According to design of experiments (DOE) specimens were injection moulded in the shape of rectangular bars. Additionally advanced technology of melt manipulation inside mold cavity after injection was used. To achieve this purpose Ferromatik Milacron injection moulding machine, equipped with externally controlled mold was used. Findings: Addition of nanoclay clearly presents highly reinforced system, especially for neat matrix. Evenly dispersed PC particles within PP majority show reinforcement as well. Inducement of shear rate in injection moulding radically improved absorption of energy in nanocomposite. Research limitations/implications: Different variation of material composition, such combination with other polymers and use of different reinforcements (flexible or either rigid) is required to be checked in the further work. Practical implications: Reinforcement obtained thanks to dispersed phase and nanofillers creates composites with improved mechanical properties. Originality/value: Morphology development reflects on mechanical behaviour. Its manipulation may affect and improve mechanical properties. Use of advanced technologies opens wide range of possibilities in processing of polymer based systems. At present there is limited number of research of processing-structure-properties relationships of polymer-polymer composites and nanocomposites.

Effects of process parameters on material removal rate in WEDM

Abstract: Purpose: In this paper, the effects of various process parameters of WEDM like pulse on time (TON), pulse off time (TOFF), gap voltage (SV), peak current (IP), wire feed (WF) and wire tension (WT) have been investigated to reveal their impact on material removal rate of hot die steel (H-11) using one variable at a time approach. The optimal set of process parameters has also been predicted to maximize the material removal rate. Design/methodology/approach: The experimental studies were performed on ELECTRONICA SPRINTCUT WEDM machine. Findings: The material removal rate (MRR) directly increases with increase in pulse on time (TON) and peak current (IP) while decreases with increase in pulse off time (TOFF) and servo voltage (SV). Practical implications: Wire electrical discharge machining (WEDM) is a specialized thermal machining process capable of accurately machining parts which have varying hardness, complex shapes and sharp edges that are very difficult to be machined by the traditional machining processes. The practical technology of the WEDM process is based on the conventional EDM sparking phenomenon utilizing the widely accepted noncontact technique of material removal. Originality/value: We can say that the wire feed and wire tension are neutral input parameters.