Özgür METİN, 030040004, 7th Week

High-feed Milling (March 26, 07:49)

High-feed milling is a roughing technique that works with cutters and inserts designed specifically for the technique. Inserts typically feature large sweeping radii and positive rakes. The high-feed method takes advantage of small setting angles (55° or less). This produces a minimal radial and a maximum axial cutting force. As a matter of fact, the cutting forces are directed towards the machine spindle in the axial direction. This is the stiffer direction of the machine, which reduces the risk for vibrations and stabilizes machining.

This allows for higher cutting parameters even when machining with a large overhang. Therefore, instead of cutting with greater depth, it does the opposite: it pairs shallow depth of cut with high feed per tooth, in some cases higher than 1.5 mm.

At the same time the axial depth of cut is very small, leading to a near-final shape in the case of complex surfaces. Consequently semi-finishing operation is eliminated. This greatly reduces the machining time in the case of moulds or dies.

(Davim J. P., Machining of hard materials, p. 76)

Electrochemical deburring (March 26, 08:25)

Electrochemical deburring (ECD) is a special version of ECM (Fig. 39). ECD was developed to remove burrs and fins or to round sharp corners. Anodic dissolution occurs on the workpiece burrs in the presence of a closely placed cathodic tool whose configuration matches the burred edge. Normally, only a small portion of the cathode is electrically exposed, so a maximum concentration of the electrolytic action is attained. The electrolyte flow usually is arranged to carry away any burrs that may break loose from the workpiece during the cycle.

Voltages are low, current densities are high, electrolyte flow rate is modest, and electrolyte types are similar to those used for ECM. The electrode (tool) is stationary, so equipment is simpler than that used for ECM. Cycle time is short for deburring. Longer cycle time produces a natural radiusing action.

(Kutz M., Mechanical engineers’ handbook 3rd edition: Manufacturing and management, p. 228)

High Removal Rate Machining (March 31, 01:20)

HRR Machining involves the use of extremely rigif, high-power, high-precision machines, such as roll turning lathes, to achieve material removal rates far beyond the capacity of conventional machine tools.

(Black J. T., Introduction to Machining Processes)