Due to PCBN insert has advantages of high hardness, good wear resistance, strong chemical stability and excellent thermal conductivity，PCBN insert is widely used in hard turning processing.
In order to make PCBN blade give full play to its performance, blade edge treatment is a problem that must be considered. Whether PCBN blade blade treatment is reasonable directly affects the tool life.
Tool preparation is a way to increase tool life. Improve tool quality through leveling, polishing, deburring and other processes. This is actually a normal process before the coating of the tool after fine grinding.
What is PCBN blade edge treatment?
The cutting edge refers to the interface position of the front and back of the blade. In this position, the workpiece material is separated to form chips and the cutting edge of the processed surface. After the blade is finely ground, the cutting edge is passivated, flat and polished by chamfering, so as to improve the quality of the tool and improve the service life of the tool.
Why do we need cutting edge processing?
After grinding with diamond grinding wheel, PCBN blade often has a certain degree of micro notch, such as tiny chipping edge, saw edge, etc. In the process of cutting, the micro notch on the cutting edge is easy to expand, which will accelerate the tool wear and damage. In order to eliminate the micro-defects of the cutting edge, the cutting edge should be treated.
PCBN blade after cutting edge treatment, the blade can be strengthened, but also can improve the wear resistance of the tool, thus prolonging the tool life.
PCBN blade edge treatment form?
PCBN blade edge processing can be divided into four categories:
(1) F - not chamfer and not edge preparation
(2) E - edge preparation not chamfer
(3) T - chamfering not edge preparation
(4) S - chamfering plus edge preparation
(1) F : Sharp cutting edge , not need chamfer and not need edge preparation, this kind of cutting edge treatment form of small cutting force, small shear deformation, low cutting heat, but the cutting edge strength is low, the edge has initial defects, rarely used.
(2) E: Only need edge preparation. This kind of cutting edge treatment eliminates the machining micro-defects on the cutting edge, strengthens the cutting edge, and increases the resistance of cracking and cracking.
(3) T: Only need chamfering. This kind of cutting edge treatment form has better impact resistance, which is more suitable for cutting force reduction and high tolerance requirements.
(4) S: Need chamfering and edge preparation,which is the most common form of cutting edge processing, is also the preferred form of hard car processing. Compared with T cutting edge, S cutting edge has higher strength and fracture resistance, which can produce more stable workpiece surface quality. It is suitable for large cutting depth and intermittent machining conditions.
---EDITOR: Doris Hu