FAILED TO 15-25% IMPROVE WEAR METAL CUTTING TOOLS, TECHNIQUES FOR THE ACCOUNT OF A NEW TREATMENT, THE PROPOSED BRYANSKAYA SCIENTISTS ...
The scientists of Bryansk State Engineering and Technology Academy developed a method of processing cutting tools used in the metalworking, woodworking and pulp and paper industries, which increases their durability.
It has long been known that the magnetized tool increases its resistance to wear and tear (MT Galey, etc. The influence of magnetic field on the resistance of high-speed tools. - Machines and tools, | 4, 1981, p.31, 32).
Known methods of materials processing in the magnetic field, the source of which is a tool for processing, have drawbacks that do not allow you to control the magnetic lines of force in the incisor are technical difficulties in the management of the magnetic field, and also require the need to consider the cross-section of the constituent elements of the design to ensure effective inductance values.
With modern technology tools magnetization in a pulsed magnetic field exposure and processing, no local directional hardening, the need for some combination of the size of the processing tools and magnetizing coils, resulting in the expansion of their range. And also, in the course of this treatment requires long time for aging and technologically sophisticated equipment due to high costs.
The scientists of the Academy - PAMFILOVA EA, PG Pyrikovym and Ruhlyadko AS managed to form in the area of tool wear (cutter) optimal (favorable) set of mechanical and tribological properties.
They were able to achieve these figures that in the normal process, the magnetic field strength are set up state of magnetic saturation tool material, magnetostrictive vector compressive stresses normally orient the plane of propagation of cracks, since the respective deformation of the cutting part of the tool, and a magnetic field acting on the tool carried continuously. For example, the magnetic field strength at hardening of carbon tool steels are installed within the 1100-1300 kA / m, made of alloy - 1400-1600 kA / m, and from high-speed - 1700-1800 kA / m
Induction of the magnetic field in the tool material is possible to provide a known manner, for example, an electromagnet in contact with the cutting tool or a solenoid encompassing the cutting zone. In the latter case, direct contact between the coil and the cutting tool does not happen, and the induction of the tool material is provided through the air gap, the researchers said.
Strengthening toughness and wear resistance of steels is because the magnetization in ferromagnetic (instrument) of the material at the expense of directional orientation of free electrons is a process of displacement of domain boundaries (crystals), which consists in the growth of the volumes in which the magnetization is oriented close to the direction of the field due to the change of neighboring domains, as well as the process of changing the direction of the spontaneous magnetization of individual domains by rotation of the magnetization vector.
This characteristic also increases dispersibility of the crystallographic structure by securing the friction surface alloying elements increase the hardness, toughness, fatigue resistance, tensile strength of the tensile strength and flexural heat intensity of the friction zone in a direction of magnetization. This combination improves the wear resistance of the material in the area of instrumental magnetization state scientists.
Thus, determining the magnitude and direction of the external load F on the tool during cutting and installing the light of this position of the magnetic field lines in the magnetization of the tool material (the magnetization direction), it is possible to form in areas of wear favorable combination of mechanical and tribological properties.
The results of the analysis tool life depending on the technology of the hardening increases on average 15-25% compared with the known methods improve durability.
Contact information:
Bryansk State Academy of Engineering and Technology
241037, Bryansk, Ave Stanke Dimitrov, 3, BGITA
