Quality assurance of the high-speed tool at flat grinding

Abstract

The cutting tool is the weakest element in the technological system; therefore, its operability and reliability depend crucially on the stability of the output parameters of the technological process and its technical and economic efficiency. The share of high-speed steels in tool production reaches 65%, which is explained by their high hardness (up to 70 HRC) and heat resistance (620...650°C) in combination with a high level of strength and toughness. Due to the constantly increasing requirements for the tool and the improvement of technologies in the world production, the range of high-speed steels is changing. So, tungsten and molybdenum high-speed steels of normal productivity are being replaced by high-performance steels with a high content of vanadium and cobalt, which can improve the processing performance of parts from high-strength alloyed, corrosion-resistant steels and titanium alloys used in aircraft construction. Due to the improved cutting properties and the increased durability of these steels, the productivity and stability of the blade processing process increase.
Standards for the manufacture of high-speed tools impose high demands on the quality of their work surfaces. So, for disk milling cutters with plates of high-speed steels according to GOST 16229-81, the roughness of the front and rear surfaces of the cutting part should be no more than Rz 3.2, and that of the supporting ends should not exceed Ra 1.25. Specifications for cylindrical broaches made of high-speed steels according to GOST 28442-9 establish the roughness of the rear and front surfaces of rough and final teeth in the range of Rz 3.2 ... 1.6, the calibrating teeth - Rz 1.6 ... 0.8, the supporting ends - Ra 0.63.