Studies on Grooving Wear of High-Speed-Steel Cutting Tools : (Mechanism of Grooving Wear and Its Prevention)

Abstract

Using soft carbon steels which are very likely to cause grooving wear on high-speed steel cutting tools, studies were conducted on the mechanism of grroving wear and its prevention and following results were obtained : (1) Without changing both the tool shape and the cutting speed, the authors worked out a method by which grooving wear could be absolutely prevented or severe grroving wear could be produced according to the will of the authors. (2) It was estimated that grooving wear is caused by the corrosive action due to the lack in uniformity of positive catalytic action at the surface of work-material just behind the cutting edge. (3) Therefore, the amount of grooving wear can be decreased to a great extent by taking some effective means, e.g. by adding surface active agents to the cutting fluids and/or by using tools with a large side-cutting-edge angle. (4) Moreover, a non-soluble cutting fluid containing a certain extreme pressure additive (viz, a sulphide, which seems to promote the catalytic action caused by the virgin surface of work material) was responsible for producing a very deep groove at the boundary between work and tool (where catalytic action seems to be large). (5) Although very severe grooving wear occurred during cutting in air (dry cutting), this was entirely prevented by removing air from the cutting region by flooding some cutting fluid containing no extreme pressure additives (mineral and plant oils). (6) Increase in cutting force per unit length of cutting edge at the points where the grooving wear occurs is not the main cause of grooving wear because grooving wear can be fully prevented even with the existence of burrs (side flow) of work material and detached particles of built-up edge.