machining simulation

 

Ball End Milling  

nUMERICAL sIMULATIOn

 
Milling is today the most competent, productive and flexible-manufacturing methods for complicated or sculptured surfaces. Ball end tools are today used by the manufacturing industry for the machining of 3D free-form surfaces for dies, molds, various parts, such as aerospace components, etc. Milling data, such as surface topomorphy, surface roughness, non-deformed chip dimensions, cutting force components and dynamic cutting behavior, are very helpful, especially if they can be computationally accurately produced by means of a simulation program.

       

 

Surface Topomorphy

 

Chip cross sections

   

experiments

 

Project PENED

   
Face Milling  

3d sIMULATIOn

 
Face Milling is today the most effective and productive manufacturing method for roughing and finishing large surfaces of metallic parts. Milling data, such as surface topomorphy, surface roughness, non-deformed chip dimensions, cutting force components and dynamic cutting behaviour, are very helpful, especially if they can be accurately produced by means of a simulation program. This paper presents a novel simulation model which has been developed and embedded in a commercial CAD environment. The model simulates precisely the tool kinematics and considers the effect of the cutting geometry on the resulting roughness. The accuracy of the simulation model has been thoroughly verified, with the aid of a wide variety of cutting experiments. The proposed model has proved to be suitable for determining optimal cutting conditions for Face Milling. The software can be easily integrated into various CAD-CAM systems.

 
experiments  
 
   
Drilling  

3d sIMULATIOn

 
Twist drills are geometrical complex tools and thus various researchers have adopted different mathematical and experimental approaches for their simulation. The present research acknowledges the increasing use of modern CAD systems and subsequently using the API (Application Programming Interface) of a typical CAD system, drilling simulations are carried out. The developed DRILL3D software routine, creates, via specifying parameters, tool geometries, so that using different cutting conditions,  realistic solid models are produced incorporating all the relevant data involved (drilling tool, cut workpiece, undeformed chip). The 3D solid models of the undeformed chips coming from both cutting areas (main edges and chisel edge) are segmented into smaller pieces, in order to calculate every primitive thrust force component involved with high accuracy. The resultant thrust force produced, is verified by adequate amount of experiments using a number of different tools, speeds and feed rates. The final data derived, consist of a platform for further direct simulations regarding the determination of tool wear, drilling optimizations etc.  
 

experiments

 
 
   
WaterJet  

FEM sIMULATIOn

 

The utilization of abrasive waterjet (AWJ) cutting/drilling, and in particular its application into hard-to-cut materials, is growing. However, the mechanics of AWJ cutting is complex; the material removal process is not fully understood and, consequently, it has not been accurately modeled. In the current study, work was undertaken to mesh in a first stage the waterflow into the waterjet nozzle in order to use the finite element (FE) method to simulate the pure waterjet flow. The main objective is to investigate and analyze in detail the workpiece material behavior under waterjet impingement; a non-linear FE model (using LS-DYNA 3D code) has been developed, which simulates the erosion of the target material caused by the high-pressure waterjet flow. A combination of Eulerian–Langrangian elements is used for the waterjet and the target material, respectively, in order to handle their interaction. Damaged zones can be localized on impinged materials. Elements’ failure is handled by introducing a threshold strain after which Langrangian elements are removed. The results obtained from this numerical simulation (velocity profile, stress, erosion stages) show a good agreement with the results from previous experimental work that is available in bibliography.

 
The influence of impact angle and particle velocity is studied, while the material’s crater circularity is also evaluated. The results are found to be in very good agreement with their experimental counterparts.  

experiments

 
   
   
 
   

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