Papers by Keyword: Face Milling

Abstract: This work studies wear kinetics of index able inserts (II) made of mixed ceramics based on Russian-manufactured in case of fine milling of special hardened cast iron with globular graphite. In a wide range of cutting parameters typical for fine milling, an impact of tool insert wearing parameters on qualitative and quantitative characteristics of the cutting process have been studied. Morphological traits and nature of wear of work surfaces has been studied using optical and scanning electron microscopy. Criteria of II states, as well as specifics of contact work surface transformation, correlating with force parameters of the face milling process, have been determined.

Abstract: Carbon-fiber-reinforced plastic (CFRP) is used in various industries such as aerospace and automobile industries because of its high mechanical characteristics. However, this material is difficult to cut. Tool wear and delamination frequently occur during the drilling or cutting of CFRP. In previous studies, we developed a CFRP cutting tool using polycrystalline diamond (PCD). The PCD tool exhibited excellent cutting performance at cutting speeds as low as <120 m/min. In this study, the authors investigated the effect of cutting speed on the face milling of CFRP by using the developed PCD tool.

Abstract: Cutting of metal matrix composites (MMCs) has been considerably difficult due to the extremely abrasive nature of the reinforcements causing rapid tool wear and high machining cost. In this experimental study, three aluminium-based metal matrix composites (MMCs) were produced using a high pressure infiltration. Machining tests were carried out by face milling on the MMCs using coated carbide (HM) cutting tool at various values of feed rate, width of cut and depth of cut, under a constant cutting speed. The effect of the varied parameters on the surface roughness was investigated. The obtained results indicate that the Rz and Rp parameters are more capable to describe the influence of the milling parameters on the surface quality.

Abstract: The objective of this study is to evaluate the wear progression of cryogenically treated and untreated tungsten carbide inserts during face milling of Grey Cast Iron which is a commonly used material in machine tool beds and automotive components due to low cost, high vibration damping capability, and easiness of manufacturing. Commercially available uncoated Tungsten Carbide insert with around 6% Cobalt (Co) content were selected for the study and flank wear and nose wear were taken as the performance evaluation criteria. The results show that the cryogenically treated samples have better wear resistance than the untreated inserts which could be ascribed to the martensitic phase transformation of Co from α-Co (FCC) to ε-Co (HCP) during the cryogenic treatment.

Abstract: For the purpose of acquiring thorough understanding of the characteristics of cutting force in high and ultra-high-speed face milling of hardened steel, experimental investigations on face milling of AISI H13 steel (46-47 HRC) are conducted in the present study. The cutting speed of 1400 m/min, at which relatively low cutting force and relatively low surface roughness can be obtained at the same time, is considered as a critical value for both mechanical load and surface finish. The Taguchi method is applied to investigate the effects of cutting parameters on cutting force in different speed ranges (below and above 1400 m/min). In different speed ranges, the contribution order of the cutting parameters for the resultant cutting force is the same, namely axial depth of cut, cutting speed and feed per tooth. However, the contributions of cutting speed and feed per tooth increase substantially as the cutting speed surpasses 1400 m/min. Within the range of cutting parameters used in the present study, the optimum cutting conditions for the cutting force are cutting speed 200 m/min, feed per tooth 0.02 mm/tooth and axial depth of cut 0.1 mm.

Abstract: The effects of the feed rate and the axial and radial depth of cut in the up and down asymmetrical face milling with respect to workpiece about the orthogonal components (axial, radial and tangential) of the cutting force in the machining of cast iron DIN GGG50 with carbide inserts was evaluated. The spindle speed was remained constant. The cutting forces were acquired through a sensory system that consists of piezoelectric dynamometer, signal acquisition board and computer with appropriate software. In the end it was concluded that studies of machining forces provides a strong basis for understanding the kinematics and the dynamics of the tool and the cutting operation and it can be applied to optimize the cutting geometries and test the probabilities of tool distortions.

Abstract: An experiment of face milling of Invar36 was conducted by using coated carbide insert, the microhardness was tested and the metallographic structure was observed to figure out the principles of work-hardening. The results showed that the depth of work-hardening ranges from 80μm to 160μm among the parameters selected in the experiments. The degree and the depth of work-hardening were significantly affected by the axial depth of cut and feed per tooth. The degree and the depth of work-hardening showed a tendency to increase with the increase of the axial depth of cut and feed per tooth. Compared with the axial depth of cut and feed per tooth, cutting speed had less influence on the degree and depth of work-hardening. The degree and depth of work- hardening decreased slowly with the increase of cutting speed. Metallographic observation showed that work-hardening layer consisted of the thermal force influenced layer and the force influenced layer, while the amorphous metallographic structure was observed in the thermal force influenced layer, and lattice distortion was observed in the force influenced layer.

Abstract: The search for continuous improvement of the processes and products offered to the market combined with continuous efforts to reduce energy consumption stimulates the development of techniques and tools geared towards their optimization. Thus, this manuscript describes the application of multivariate optimization in the process of face milling of DIN GGG 50 nodular cast iron by means of experimental design techniques, regression models, and Taguchi loss function. Three input parameters (axial “a_p” and radial “a_e” depth of cut, and feed-rate “f”) were used as controllable factors of the process and two output parameters (specific cuttingenergy “e_s” and roughnessaverage “R_a”) were considered as response variables. The output obtained as a result of optimization wase_s = 1.41 J/mm³and R_a = 0.85 µm by applying the input parameters a_p = 2.34 mm,a_e = 33.4 mm and f = 0.44 mm/rev.

Abstract: The modern investigation of the topography of cut surfaces is nowadays usually performed by three-dimensional surface roughness indexes. The goal of this work was to determine a theoretical roughness index for face milled surfaces. The calculated values were compared with real surface roughness data obtained by performing cutting experiments and the relation was determined between these two datasets.

Abstract: Interest in carbon-fiber-reinforced plastic (CFRP) has been growing for the last several years. CFRP, a composite material made of carbon fibers and resins, has high mechanical characteristics and is well known as a difficult-to-cut material. During the process of drilling or cutting of CFRP, tool wear and delamination occur frequently. In this study, the authors developed a milling tool for CFRP using polycrystalline diamond, and the cutting performance of the developed tool was investigated.