FEATURES OF IRON COATING ELECTRO-GALVANIC METHOD

The paper analyzes the technological process of electro-electroplating-mechanical coating in comparison with a similar process without mechanical impact on the formed coating.

PENERAPAN PERENCANAAN KAPASITAS PRODUKSI DENGAN PERHITUNGAN METODE ROUGH CUT CAPACITY PLANNING (RCCP) DI PERUSAHAAN PANEL LISTRIK

Perusahaan panel listrik ini memproduksi Panel Listrik berdasarkan pesanan (make-to-order). Hal tersebut menimbulkan jadwal pendistribusian yang sudah dijadwalkan sebelumnya tidak mencapai waktu yang tepat, sehingga menjadikan target produksi tidak tercapai. Kapasitas produksi di perusahaan panel listrik ini yang belum mampu memenuhi beban produksi dan menyelesaikannya tepat waktu, dikarenakan kapasitas produksinya yang belum diketahui yang mengakibatkan penumpukan (bottleneck) sehingga kegiatan keterlambatan pruduksi untuk menyelesaikan dengan tepat waktu. Dalam kegiatan produksinya sering terjadi masalah penumpukan (bottleneck) yaitu pada stasiun kerja Pra Mechanical, Coating, dan Assembly. Tujuan penelitian ini akan melakukan perencanaan kapasitas produksi dari tiap staisun kerja dengan perhitungan Rough Cut Capacity Planning (RCCP) untuk memecahkan masalah perusahaan yang berkaitan dengan kapasitas produksi. Rough Cut Capacity Planning (RCCP) menghitung kebutuhan kapasitas secara kasar dan membandingkannya dengan kapasitas yang tersedia. Terjadi penumpukan pada beberapa stasiun kerja yang diperoleh dari perhitungan kapasitas produksi dengan metode pendekatan RCCP yaitu lini produksi pra assembly mechanical pada bending machine, lini produksi assembly mechanical pada assembly rangka dan drilling machine, lini produksi coating pada coating treatment, lini produksi electornic mechanical pada punching cu machine, lini produksi electrical pada assembly cu. Dengan menggunakan perhitungan Rough Cut Capacity Planning (RCCP) dapat diketahui kapasitas yang dibutuhkan untuk penambahan mesin-mesin produksi atau penambahan jumlah pekerja serta penambahan jam kerja (lembur).

Fabrication of Nickel Coatings on Zirconia Balls by Mechanical Ball Milling and the Process Analysis

The Ni coatings were prepared from nickel metal powder and zirconia ceramic balls by mechanical coating technique. The relationship between rotation speed and coatings thickness was studied, the thickness of the coatings was characterized by the weight increase of the zirconia balls after mechanical coating. The composition and microstructure of the coatings with maximum thickness were analyzed by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray Diffraction (XRD). The results revealed that the formation of coatings consists of thickening from the cold welding between Ni particles and the thinning from the exfoliation of coatings work hardening. The thickness of the coatings reaches the maximum when the above two process progress are close to each other. The results proved that higher speed was favor of the coatings formation, the maximum thickness was obtained at the 15 h for rotation speed of 240 rpm, and microscopic images show that the average thickness was about 20 μm.

Effect of Ni3Al Coating on Vibration Suppression of Beams of Various Thicknesses

High cycle fatigue (HCF) caused by the vibratory stresses is the main cause of failure in many machine components, e.g. aircraft engine and gas turbine components, which has caused loss of many lives and billions of dollars. To avoid these kind of failures, vibratory stresses should be attenuated to an acceptable level, especially at resonant frequencies. A lot of previous studies have shown that thin coatings of different materials significantly reduced these vibratory stresses by adding extra damping to the system. These include viscoelastic materials, plasma graded coatings, piezoelectric materials, and magneto-mechanical damping material coatings, but some of these had applicability and performance issues. Among these thin coatings, magneto-mechanical materials are very effective in reducing these vibratory stresses significantly.In this study, the effect of different beam structure thicknesses under same magneto-mechanical coating of 0.2mm was studied. For this purpose, Ni3Al was applied as magneto-mechanical coating. The natural frequencies, damping ratios and displacements of beams were calculated before and after applying magneto-mechanical coatings using forced response analysis and hammer tests. The results indicated a sharp change in vibration characteristics i.e. natural frequency, damping ratio and beam deflections, of all the beams used. The results showed that the magneto-mechanical coatings were more effective when applied to thin structures as compared to thick structures, because thin structures have higher strains, which enabled magneto-mechanical coatings to dissipate larger amounts of energy of applied loadings, because performance of these coatings is strain dependent.