When the tungsten carbide milling cutter is milling, the workpiece can be fed along or relative to the direction of rotation of the tool, which affects the start and finish characteristics of the cut.
When the tungsten carbide milling cutter is performing climb milling (also known as co-milling), the feed direction of the workpiece is the same as the rotation direction of the tungsten carbide milling cutter in the cutting area. The chip thickness is gradually reduced from the outset until the end of the cut reaches zero during perimeter milling, and in conventional milling (also known as reverse milling), the workpiece is fed in the opposite direction of the cutter rotation in the cutting area. The chip thickness starts at zero and then gradually increases as the cutting process progresses.
Carbide cutter In conventional milling, the tungsten carbide cutter insert starts cutting from zero chip thickness, which creates a high cutting force that pushes the tungsten carbide cutter and the workpiece away from each other. When the tungsten carbide cutter insert is forcibly pushed into the cut, it usually comes into contact with the machined hardened surface caused by the cutting blade, and at the same time produces friction and polishing effects under the action of friction and high temperatures. The cutting forces also make it easier to lift the workpiece off the table.
When carbide milling cutters are milling, the tungsten carbide cutter insert starts cutting from the maximum chip thickness. This avoids the polishing effect by reducing the heat and weakening the hardening tendency. It is very advantageous to apply the maximum chip thickness, and the cutting force makes it easier to push the workpiece into the tungsten carbide cutter to allow the tungsten carbide cutter insert to perform the cutting action.
When milling a tungsten carbide cutter, the chips are sometimes bonded or welded to the cutting edge and collect around the start of the next edge cut. In conventional milling, chip breaks are more likely to be trapped or wedged between the insert and the workpiece, which can lead to insert breakage. In climb milling, the same chip break is split in two, so that the cutting edge is not damaged.
Regardless of the requirements of the machine, fixtures and workpieces, climb milling is the preferred method.
Because the cutting force keeps the workpiece down and easy to push the insert forward, the climb milling has certain special requirements for the machining process. This requires the machine to handle the table feed requirements by eliminating backlash. If the tool is pushed into the workpiece, the feed increases irregularly, resulting in excessive chip thickness and chipping. Conventional milling should be chosen for this application. In addition, if there is a large change in machining allowance, it is more advantageous to choose conventional milling. In order to clamp the workpiece correctly, it is necessary to have the right fixture, and the same is required to have the correct tool size for the job. However, for the vibration trend, the cutting force direction is even more important.
