International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Electrochemical machining (ECM) is prevalent and competitive manufacturing process which uses for machining of hard and tough materials in high tech industries. Hence, experimental investigations on ECM of different materials play essential role to effectively utilize this process. This paper demonstrates a systematic approach for achieving comprehensive mathematical models in order to investigate the effect of machining parameters on the process responses of 321-Stainless-Steel and analysis of machining performance based on the response surface methodology (RSM). Machining voltage, tool feed rate, electrolyte flow rate and concentration of NaNO3 solution were considered as the machining parameters while material removal rate (MRR) and surface roughness (Ra) were considered as the process responses. Experimental plan was performed by a central composite design (CCD), and the proposed mathematical models statistically have been evaluated by analysis of variance (ANOVA). Analysis shows that the RSM method has been appointed properly as the design of experiments (DOE) method for resolving curvature in ECM process responses. Also, the results show that the machining performance is greatly influenced by machining parameters. Especially the voltage and electrolyte concentration are the most important parameters.

Electron beam irradiation has the ability to modify polymer substrates by the process of graft copolymerization in order to synthesize water-soluble copolymers having flocculating properties. The influence of the variation of the process parameters acrylamide/starch (AMD/St) weight ratio, electron beam irradiation dose and dose rate is investigated. Models of the means and variances for the dependencies of the quality characteristics (monomer conversion coefficient, residual monomer concentration and apparent viscosity) from the described process parameters are estimated by implementation of the robust engineering methodology for quality improvement. Multi-criteria optimization involving requirements for economic efficiency, assurance of low toxicity and high copolymer efficiency in flocculation process is also presented.

Electron beam (EB) irradiation has the ability to modify polymer substrates by process of graft copolymerization to synthesize water-soluble copolymers having flocculating potential. Models – depicting the dependencies of the described quality characteristics (their means and variances) from process parameters – are estimated by implementation of the robust engineering methodology for quality improvement. Multiple criteria optimization based on the desirability function approach, involving requirements for economic efficiency, assurance of low toxicity, high copolymer efficiency in flocculation process, good solubility in water, bias, robustness, quality of prediction and the relative importance of responses, is presented.

Experimental investigation of the modification of starch by grafting acrylamide using electron beam irradiation in order to synthesize water-soluble copolymers having flocculation abilities is performed. The influence of the variation of the parameters acrylamide/starch (AMD/St) weight ratio, electron beam irradiation dose and dose rate, as well as the presence or absence of metallic silver nanoparticles is investigated. The characterization of graft copolymers was carried out by monomer conversion coefficient, residual monomer concentration, intrinsic viscosity and Huggins’ constant. Models, describing the dependencies of the quality characteristics (their means and variances) from the process parameters, are estimated by implementation of the robust engineering approach in the case of qualitative and quantitative factors. Multi-criteria optimization involving requirements for economic efficiency, assurance of low toxicity, high copolymer efficiency in flocculation process and good solubility in water is also presented.

This paper demonstrates a systematic approach for achieving comprehensive mathematical models for electrochemical machining (ECM) of 321-stainless steel based on the response surface methodology (RSM). Machining voltage, tool feed rate, electrolyte flow rate and concentration of NaNO3 solution were considered as the machining parameters while material removal rate (MRR) and surface roughness (Ra) were considered as the process responses. Experimental plan was performed by a central composite design (CCD).

The proposed mathematical models statistically have been evaluated by analysis of variance (ANOVA). Analysis shows that the RSM method has been appointed properly as the design of experiments (DOE) method for resolving curvature in ECM process responses. Also, the optimal machining parameter for single optimization of MRR and Ra is determined by desirability function. The results showed that the proposed approach is an effective and suitable way for modeling and optimization of the ECM machining process.