Optimization of injection molding parameter of ti-6al-4v powder mix with palm stearin and polyethylene for the highest green strength by using taguchi method

This paper present the Taguchi method of L27 (313) orthogonal array as a tool in optimization of Metal injection molding (MIM) parameters for the highest green strength. Injection pressure, injection temperature, powder loading, mold temperature, holding pressure and injection speed are Parameters to be optimized. Besides those, interaction of the injection pressure, injection temperature and powder loading were studied. The metal powder of Ti-6Al-4V is mixed with binder 60wt% of palm stearin and 40wt% of polyethylene successfully injected at optimum parameter condition: 350 bar of injection pressure, 140oc of injection temperature, 65vol% of powder loading, 50oc of mold temperature, 600 bar of holding pressure, and 10ccm/s of the injection rate. Analysis of variance (ANOVA) for the best signal to noise ratio (S/N) presents the contribution of the parameters to the quality characteristic (green strength). Results show that the mold temperature has highest significant percentage (27.59%) followed by powder loading (15.44%) and injection pressure (12.30%) Nevertheless, the analysis of variance does not show any contribution from interaction

Musculoskeletal MRI protocol

The authors propose a musculoskeletal (MSK) magnetic resonance imaging (MRI) protocol using selected sequences for common orthopaedic indications. Selected sequences allow optimal visualisation of the indicated pathology while screening for other common conditions. The authors emphasise the need for standard positioning of the patient and standard orientation of scan planes to facilitate comparison with follow-up scans

Spectral curve fitting of dielectric constants

Optical constants are important properties governing the response of a material to incident light. It follows that they are often extracted from spectra measured by absorbance, transmittance or reflectance. One convenient method to obtain optical constants is by curve fitting. Here, model curves should satisfy Kramer-Kronig relations, and preferably can be expressed in closed form or easily calculable. In this study we use dielectric constants of three different molecular ices in the infrared region to evaluate four different model curves that are generally used for fitting optical constants: (1) the classical damped harmonic oscillator, (2) Voigt line shape, (3) Fourier series, and (4) the Triangular basis. Among these, only the classical damped harmonic oscillator model strictly satisfies the Kramer-Kronig relation. If considering the trade-off between accuracy and speed, Fourier series fitting is the best option when spectral bands are broad while for narrow peaks the classical damped harmonic oscillator and the Triangular basis fitting model are the best choice

A review of workability of wrought magnesium alloys

Despite being the lightest structural metal, magnesium alloys exhibited poor workability at low temperatures due to their hexagonal closed-packed crystal structure, consequently required them to be processed at elevated temperature. Their highly affinity to oxygen lead them to an easy oxidation. Moreover, they are poor corrosion resistance, poor creep resistance as well as fatigue failure but these can be improved by various techniques of surface treatments and alloying additions. Commercial wrought magnesium alloy grades, its mechanical properties as well as its workability at elevated temperatures are presented. Recent literatures showed that the workability of these alloys is increased at temperatures ranging from 100 to 3500C, 200 to 400 to 300 to 5000C and for AZ, ZK and WE alloy systems, respectively. The purpose of this paper is to review and reveal the issues in processing of wrought magnesium alloy

Spectral curve fitting of dielectric constants

Optical constants are important properties governing the response of a material to incident light. It follows that they are often extracted from spectra measured by absorbance, transmittance or reflectance. One convenient method to obtain optical constants is by curve fitting. Here, model curves should satisfy Kramer-Kronig relations, and preferably can be expressed in closed form or easily calculable. In this study we use dielectric constants of three different molecular ices in the infrared region to evaluate four different model curves that are generally used for fitting optical constants: (1) the classical damped harmonic oscillator, (2) Voigt line shape, (3) Fourier series, and (4) the Triangular basis. Among these, only the classical damped harmonic oscillator model strictly satisfies the Kramer-Kronig relation. If considering the trade-off between accuracy and speed, Fourier series fitting is the best option when spectral bands are broad while for narrow peaks the classical damped harmonic oscillator and the Triangular basis fitting model are the best choice.</p

Injection molding parameter optimization of titanium alloy powder mix with palm stearin and polyethylene for multiple performance using grey relational analysis

This paper outlines the optimization the process of injection molding parameters for feedstock of titanium alloy powder and palm stearin binder using grey relational analysis method. A Grey Relational Grade (GRG) obtained from the Grey Relational Analysis (GRA) is used to solve the inj ection molding operations with the multiple performance characteristic. The L27 (313) of orthogonal array of Taguchi method were performed. Defects, strength and density are important characteristics in determine the quality of the green part. Using these characteristics, the injection pressure, injection temperature, powder loading, mold temperature, holding pressure and injection speed are optimized in the study. From the analysis of variance (ANOVA), the injection temperature has the highest contribution to the quality of green part followed by injection pressure, powder loading, mold temperature, injection rate and holding pressure

Implementasi Manajemen Kearsipan Dalam Ketatausahaan di Madrasah Tsanawiyah Darul Ulum Kubu Raya

This research was conducted to find out more about the implementation of archives management in administration at Madrasah tsanawiyah Darul ulum Kubu raya by discussing several topics. First, how is the implementation of archives management in administration. Second, what obstacles are faced and efforts to overcome obstacles regarding archive management in administration at madrasah tsanawiyah Darul ulum Kubu raya. The method used in this research is a descriptive method with a qualitative approach. The main data source in this research is the head of administration and staff as an active component in the archive management implementation process obtained through interviews, observation and documentation. Based on the research results, the results of this research are: The implementation of archives management at the madrasah tsanawiyah Darul ulum Kubu raya can be classified in the good category, because it has implemented several indicators regarding archives at the madrasah tsanawiyah Darul ulum Kubu raya, such as recording, distribution, use, maintenance, and deletion of archives, however, as time goes by, it is necessary to always keep abreast of emerging technological developments in order to remain in a good position. Apart from good implementation, of course there are obstacles faced by resolving various obstacles faced in the administration section at madrasah tsanawiyah Darul ulum Kubu raya, such as experiencing difficulty in finding archives that have been stored for a long time, due to the large number of archives that have accumulated. But after being found the archive had been eaten by termites. This is due to inadequate infrastructure. Adding facilities is also hampered by limited space. Several efforts have been made to overcome obstacles in managing archives at the madrasah tsanawiyah Darul ulum Kubu raya, namely copying the archives into computers so that they are not lost and not damaged, in addition to renovating the building, especially the administration room at Madrasah tsanawiyah Darul ulum Kubu ray