Machining of carbon fiber-reinforced polymer (CFRP) is a rather hard task due to the inhomogeneity and anisotropy of this material. Several defects occur in the material when CFRP is machined and machining quality deteriorates owing to these material properties. In recent years, liquid nitrogen has been considered an environmentally safe, clean, and non-toxic coolant used to cut various materials in order to enhance machinability and prevent damage during machining. In this study, a new, eco-friendly cryogenic machining technique called dipped cryogenic machining was applied for the drilling of CFRP. This experimental study investigated the effect of feed rate and drill diameter on the thrust force, delamination factor, surface quality and drill wear. Machined surfaces were analyzed in detail using a scanning electron microscope and atomic force microscope. Results indicated that the drilling of CFRP with the dipped cryogenic machining approach greatly improved machinability by reducing the surface roughness of the drilled parts and tool wear. However, it increased the thrust force and delamination factor.

Compared to milling on a macro scale, the micromilling process has several cumbersome points that need to be addressed. Rapid tool wear and fracture, severe burr formation, and poor surface quality are the major problems encountered in the micromilling process. This study aimed to reveal the effect of cutting path strategies on the cutting force and surface quality in the micromilling of a pocket. The hatch zigzag tool path strategy and the contour climb tool path strategy under different cooling conditions (e.g., dry, air blow, and flood coolant) at fixed cutting parameters. The micromilling tests revealed that better results were obtained with the use of the contour tool path strategy in terms of cutting forces (by up to ~43% compared to the dry condition) and surface quality (by up to ~44% compared to the air blow condition) when compared to the hatch tool path strategy. In addition, the flood coolant reduces the cutting temperature and eliminates chips to significantly enhance the quality of the micro milled surface.

Machinability and optimization are the two objectives of researchers who guide us to enhance the manufacturing industry. Examining and analyzing the parameters such as surface roughness, tool wear, and cutting force during the processing would be beneficial that are used in various fields in the manufacturing industires. This study examined the effect of cutting forces to surface roughness on the material surface. Experimental studies were carried out by using constant feed rate (0.1 mm/rev), depth of cut (1 mm), three different coolants (CO₂, minimum quantity lubrication, and dry), and cutting speeds (100, 140, 180, 220 m/min). In this study, grey relational analysis modeling and analysis of relationships between F _x , F _y , and F _z forces on the surface roughness of Inconel 718 material, which is an important alloy in aviation, is examined. The influence of machinability parameters on F _top and R _a was calculated using variance analysis, which determined that cutting speed was the most significant machining parameters.

Tr en Bu çalışmada ASTM B574 (Hastelloy C-22) malzemesi üzerinde tornalama işlemi sonrasında kesme parametrelerinin (kesme derinliği, kesme hızı, radius, ilerleme hızı, debi, talaş açısı, yanaşma açısı) yüzey pürüzlüğü ve sıcaklık üzerindeki etkileri incelenmiştir. Kesme parametrelerini etkileyen faktörleri belirlemek için varyans analizi (ANOVA) uygulanırken, yüzey pürüzlülüğünü etkileyen parametrelerin optimizasyonu Taguchi ortogonal deney tasarımına dayanan Tepki Yüzeyi Metodolojisi (RSM) ile elde edilmiştir. Geliştirilen modellerin yüzey pürüzlülüğü ve sıcaklık tahmini için gerekli olan doğruluğu oldukça başarılıdır. Ölçüt olarak değerinin kullanıldığı çalışmada ortalama Ra yüzey pürüzlüğü için %93.85, doğruluk değeri elde edilmiştir. ANOVA analizleri sonucunda %95 güven aralığında, Ra için en etkili parametreler sırasıyla kesme hızı, yanaşma açısı, talaş açısı ve debi olarak tespit edilmiş ve en düşük yüzey pürüzlüğü oranı için en uygun kesme parametre değerleri belirlenmiştir. In this study, the impact of cutting parameters (depth-of-cut, cutting speed, feed, flow, rake angle, lead angle) on surface roughness in the turning process with regard to ASTM B574 (Hastelloy C-22) material has been investigated. Variance analysis (ANOVA) has been applied in order to determine the factors affecting the surface roughness. The optimization of the parameters affecting the surface roughness has been obtained using Response Surface Methodology (RSM) based on the Taguchi orthogonal experimental design. The accuracy required for surface roughness and temperature estimation of the developed models is quite successful. As a criterion, when the value of R² is used, 93.85% accuracy value is obtained for the average Ra surface roughness. As a result of ANOVA analysis, the most effective parameters for Ra were determined as cutting speed, lead angle, rake angle and flow rate, respectively, at 95% confidence interval and optimal cut parameter values were determined for the lowest surface roughness ratio.