Jozef Beňo

Finite Element Simulation of Cutting Forces in Orthogonal Machining of Titanium Alloy Ti-6Al-4V

In this paper, a Lagrangian finite element-based machining model is applied in the simulation of cutting forces in two-dimensional orthogonal cutting of titanium Ti-6Al-4V alloy. The simulations were conducted using 2D Finite Element Method (FEM) machining simulation software. In addition, the cutting experiments were carried out under the different cutting speed, feed and tool geometry (rake angle, clearance angle and cutting edge radius). The effect of cutting speed, feed and tool geometry on cutting force were investigated. The results obtained from the finite element method (FEM) and experimental studies were compared.

Sampling Based Assessment of the Free-Form Milling Strategies

In this paper, author introduce common needs of increasing surface quality in tool making, a sort of products manufactured by free form milling technology. Principles of the free-form surface decomposition into measurable samples are presented and that is a method of combining CAD modeling with design of sampling objects. Sampling objects are classed both according to their measurability and applied milling strategy. Authors verify experimentally their sampling approach for three milling strategies applied in surface finishing operations while free-form surfaces are investigated in terms of their signed radii. Verification of proposed approach is based on statistical distribution of the measured surface roughness data.

Modelling and Analysis of Relationship between Cutting Parameters Surface Roughness and Cutting Forces Using Response Surface Methodology when Hard Turning with Coated Ceramic Inserts

Experimental research and modeling in the field of turning hardened bearing steel with hardness of 62 HRC using TiN coated mixed oxide ceramic inserts is presented. The main objective of the article is investigation the relationship between cutting parameters (cutting speed and feed rate) and output machining variables (surface roughness and cutting force components) through the response surface methodology (RSM). The mathematical model of the effect of process parameters on the cutting force components and surface roughness is presented. Moreover, the influence of TiN coating on above mentioned variables was monitored. The design of experiment according to Taguchi L9 orthogonal matrix (32) was applied for trials. Pearson´s correlation matrix was used to examine the dependence between the factors (f, vc) and the machining variables (surface roughness and cutting force components). The results show how much surface roughness and cutting force components is influenced by cutting speed and feed in hard turning with coated ceramics.

Adaptive Control System to Assist the Surface Workpiece Quality when Drilling

Article deals with design of adaptive control system for drilling process of aerospace critical components. The system proposed in this paper is directed towards real the time control of surface roughness parameter Ra. Proposed model for monitoring and control consists of surface roughness prediction system and decision making subsystem. The artificial neural network was employed to calculate surface roughness parameter Ra through of process monitoring indices such as torque Mz, force Fz, power P and cutting conditions feed f, cutting speed vc. Test samples were nickel based super alloy Udimet 720 used as a basic constructional material of discs for gas turbine engines.

Milling strategies evaluation when simulating the forming dies’ functional surfaces production

Abstract The paper deals with selection and evaluation of milling strategies, available in CAM systems and applicable when complicated shape parts are produced, such as forming dies. A method to obtain samples is proposed and this stems from real forming die surface machined by proper strategies. The strategy applicability for the whole part – forming die – is reviewed by the particular specimen evaluation. The presented methodology has been verified by machining model die and comparing it to the production procedure proposed in other CAM systems.

The Evaluation of Surface Quality for Particular Parts of Forging Die

Forming dies are often costly for producers and the cost amount is influenced by production process too. If the die is manufactured by machining, proper strategies would necessary to consider as well. The right selection of adequate strategy helps production times shortening, tool wear reducing and those affect production effectiveness. Used strategies and its parameters are often compromise between acceptable surface quality and variations in shape aside, and production time on the other side. The paper presents the way of evaluation of milling strategy based on selected elements of forming die. This allows choosing the adequate strategy for particular shapes of die and also to evaluate them by the reached surface quality. Presented approach is verified by machining forging die cavity for production of connecting rod.

Comparison of Experimental Stamping Punch Machinability Made out of Unconventional Materials

The paper describes experimental stamping punch production from the view machinability and quality of stamping punch active surfaces. The tin car-body stamping punch has been chosen as a subject of experimental work. Two unconventional materials such as Textit J and Fibroflex 5 have been chosen for stamping punch. Milling strategies have been proposed, optimized and verified using CAM software SolidCAM considering the maximum Scallop Height. The final surface quality on selected areas of stamping punch shaped surface has been evaluated by surface roughness parameters Ra and Rz. These have been compared to Scallop Height set in CAM software. Manufactured areas on shaped surface were optically evaluated as well.

The Combined Approach to the Evaluation of the Cutting Force Data when Ball End Milling

This paper introduces chosen results from measuring cutting forces when end ball milling as well as combined approach to their evaluation. Such a combined approach involves Taguchi array and Response Surface Methodology while main cutting data as depth of cut and side step and cutting speed and feed rate have been taken into account. Main effects of cutting data mentioned above have been identified by means of statistical formulae expressing testing conditions of ball end milling cutters. Interactions among all the cutting conditions are capable of finding out optimized radial and axial depth of cut which are derived from the measured components of the cutting force.

Investigation of the Surface Quality when End–Ball–Milling Form Surfaces with Sequence of the Radii Ratio

This paper deals with a methodology of identifying surface quality when endball milling form surfaces which are applied in tool making. This methodology was developed for the 3D milling process and it consists of following parts as design of the samples, surface milling and checking surfaces with different sequence of radii ratio. That sequence was used to model real form surfaces applied in tool making. Based on the defined measurability of the surface roughness, two milling strategies have been applied to produce radii sequence. In order to prevent undesired cusp formation in the 3D milling, the response surface methodology and statistical analysis are used to evaluate surface quality.

Statistical Analysis of Cutting Force, Temperature and Power of FEM Modeling when Machining Titanium Alloy

FEM analysis was performed on design of experiment (DoE) according to Taguchi plan L9 (34). In order to overcome the machinability issues associated with machining of Ti-6Al-4V alloy, an attempt has been made in this study to observe the effect of friction coefficient, cutting speed, feed rate and cutting edge radius and on cutting force, temperature and power in 2D orthogonal cutting process supported through out with Third Wave Systems’ AdvantEdge. The comparison between the predicted cutting force, temperature and power at varying of friction coefficient, cutting speed, feed rate and cutting edge radius are presented and discussed. Evaluation of obtained results was processed by the statistical software Minitab 16.