Sculptured/curved surfaces, today, are widely used in several industries, for instance, automotive, aerospace, bio-medical components, precision machine design and die-mould industries. Recent improvements in CAM software have allowed the manufacturing of complex curved geometries. The ball-end/nose milling is a flexible process that is capable of milling both convex and concave part surfaces with rough, semi-rough and finish processes. The sculptured surface milling is mostly realized by the repeated motion of a rotating cutter along predefined trajectories. Manufacturing engineers can choose the cutter paths generation approach from a set of typical paths (zig, zig-zag, concentric, radial tool paths, etc.) in commercial CAM software. In addition, these strategies cannot be optimized for all complex surfaces to be milled. A substantial number of studies have examined this subject, and many path-generation approaches have been developed, as shown in Fig. 1 [1] and [2].The strategies can be sorted into three basic categories: offset, single direction, and raster. In offset milling, the cutter starts at the periphery of the face and then proceeds spirally inwards. In a raster milling strategy (zig, zig-zag, or sweep) the cutting tool moves back and forth across the milled workpiece [3]. In spiral milling, the cutter returns to the start-point of each cycle and then cuts outwards to the next outer cycle. When using a spiral strategy, the cutting time is hugely decreased. The selection of the proper milling strategy in the process of milling will decrease cutting time, improve the surface quality of the finished part and tool life and reduce machining costs and cutting forces. Kurt

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Composite materials are widely used in the marine industry. The marine environment, on the other hand, has a significant impact on the strength of composite materials. The tensile strength is adversely affected because the matrix material absorbs water. In this study, the effect of orientation, number of layers and different mediums over time on the tensile strength of the woven carbon fiber reinforced epoxy composite material was investigated experimentally from a comprehensive perspective. The findings of the experiments were subjected to variance analysis. The repeated tests and cross-results of the experimental parameters were found to be compatible with each other. Seawater reduces the tensile strength of composite materials in any case. The tensile strength increased with increasing the number of layers. However, it has been observed that the seawater medium reduces strength when the number of layers increases. At the same time, as orientation angle rises, the seawater medium’s negative effect on strength rises.

Mühendislik yapılarında fiber/epoksi kompozitler, dayanıklılık ve hafifliği nedeniyle yaygınca kullanılmaktadır. Tasarımcılar açısından kompozit malzemenin seçimi için fiber tipi, katman sayısı, yüklemeye maruz kalacağı açı, yükleme hızı gibi çeşitli durumlarda malzemenin mukavemetinin nasıl değiştiği önemlidir. Bu çalışmada, bu parametreler ışığında tam faktöriyel bir deney tasarımı kurulmuş ve parametrelerin birbirleri üzerindeki çapraz etkileri; maksimum çekme gerilmesi, birim şekil değiştirme ve yapı tarafından depo edilen enerji açısından değerlendirilerek tasarımcılar için kullanışlı sonuçlar ve gözlemler elde edilmiştir. Fiberlerin yönelim açısı mukavemet üzerinde çok etkili olsa da; değişik kalınlıklarda, hızlarda ve fiber tiplerinde farklı oranlarda mukavemeti değiştirmektedir. Bu açıdan bahsedilen parametrelerin birbirlerini çapraz olarak etkilediği söylenebilir.