• Journal of Mechanical Science and Technology
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• v.18 no.5
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• pp.753-761
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• 2004

In this paper, an efficient method for generating 5-axis cutting data for a turbine blade is presented. The interference elimination of 5-axis cutting currently is very complicated, and it takes up a lot of time. The proposed method can generate an interference-free tool path, within an allowance range. Generating the cutting data just point to the cutting process and using it to obtain NC data by calculating the feed rate, allows us to maintain the proper feed rate of the 5-axis machine. This paper includes the algorithms for: (1) CL data generation by detecting an interference-free heel angle, (2) finding the optimal tool path interval considering the cusp-height, (3) finding the adaptive feed rate values for each cutter path, and (4) the inverse kinematics depending on the structure of the 5-axis machine, for generating the NC data.

• Horticultural Science & Technology
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• v.16 no.1
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• pp.33-36
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• 1998

This study was carried out to examine the effects of cutting dates and rooting promoters on rooting of the Rhododendron mucronulatum Turcz. The rooting percentage in greenwood cutting was high in June and decreased after July 3, when reproductive growth began. The best rooting percentage(92.5%) occurred when cutting was completed on June 12. There was no difference in rooting potentials between the greenwood straight cutting and the greenwood heel cutting. Cuttings of R. mucronulatum for. albiflora showed high rooting percentage(85%) similar to the cuttings of R. mucronulatum. Dipping cuttings in NAA $2,000mg{\cdot}L^{-1}$ solution for 15 sec increased the rooting percentage up to 97.5%, and also promoted root growth.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.862-867
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• 1997

A 5-axis NC milling technology is presented on ruled surface. Problems in 5-axis NC machining are such as tool interference,tool collision and change of tool attitude,etc. The change of tool attitude causes rotation of cutter and variation of feedrate to overcut part surface. This poor control of tool attitude is the primary problem in multi-axis NC milling. This paper observes ruled surface for control of tool attitude. Ruled surface is composed of directrix and ruling, line of constant magnitude. Directrix corresponds to points on part surface and Ruling cutting tool. Trajectory of tool movement corresponds to ruled surface.

• Korean Journal of Computational Design and Engineering
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• v.4 no.2
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• pp.110-120
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• 1999

In general, turbine blades are usually machined on 5-axis NC machine. The 5-axis machining of sculptured surface offers many advantages over 3-axis machining including the faster material-removal rates and an improved surface finish. But it is difficult and time-consuming to generated interference-free 5-axis tool path. This paper describes research on the algorithm for generation of an interference-free 5-axis NC data for machining turbine blades. The approach, using the section profile derived from the intersection of cutting planes with a triangulated-surface approximation, includes (1) CL-data generation by detecting an interference-free heel angle (2) the calculation method for finding a adaptive feed-rate value, and (3) the inverse kinematics depending on the structure of 5-axis machine.

• Journal of Welding and Joining
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• v.32 no.6
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• pp.22-28
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• 2014

Most publications on friction stir welding describe phenomena or results with given process parameters like feed rate, rotation speed, angle and depth of penetration. But without a complete documentation of tool design, the results under the same process parameters are completely different. For this purpose, the Institute of Cutting and Joining Manufacturing Processes (tff), University of Kassel investigated the influence of tool roughness on the friction stir welding process. Therefore a defined surface finish was produced by turning and die sinking. As basis of comparison the constant parameters were rotation speed, feed rate, tilt angle and a heel plunge depth. Sound butt-welds were produced in aluminium alloy 6082 (AlMgSi1) with 1.5 mm sheet thickness with a turned reference tool with a surface of $Ra=0.575{\mu}m$ in position controlled mode. The surfaces are manufactured from a very fine to a very rough structure, classified by the VDI-classes with differences in the arithmetical mean roughness. It can be demonstrated with the help of temperature measures, that less heat is generated at the surfaces of the shoulder and the pin by the higher roughness due to lower active friction contact surface. This can also be seen in the resulting wormhole defects.