Control and monitoring system prototype for pulse plasma sintering process
Cubic boron nitride is commonly used as a cutting tools material for the sake of its high hardness and wear-resistance. Pulse Plasma Sintering was proposed to decrease the production costs. This method is very attractive for industry, because it significantly decreases the costs of production. The goal of this paper is to present the control system prototype for Pulse Plasma Sintering processes based on programmable logic controller. Only sintering process with carefully controlled parameters allows to restrict the transformation of cBN into hBN and guarantee production of high-quality cubic boron nitride samples. Thus a dedicated control system was developed to control parameters and therefore to improve the production process. This paper presents also a visualisation system which allows the operator to control, monitor and analyze the production process. Prepared application consists of manual and auto operating mode.
The Effect of Chemically Active Media on the Structure and Properties of Cubic Boron Nitride
Properties of cubic boron nitride (cBN) powders from 2 to 200 mm particle size have been studied before and after chemical treatment. Impurity compositions of the bulk and surface, density, magnetic, electrophysical, physicochemical, and radio-spectroscopic characteristics are considered. Structural changes in samples and the origin of the observed effects are discussed.
Sintering behavior and properties of diamond/cemented carbides
Dense diamond/cemented carbides were fabricated at around 1300 °C, 41 MPa for 3 min under meta-stable conditions for diamonds by pulsed-electric current sintering. Diamond particles were coated with SiC to prevent the graphitization of diamond with molten binder during sintering. No graphitization of diamond was confirmed by microstructure observation and Raman scattering analysis. The combination of SiC coating of diamond and rapid sintering was effective to fabricate diamond/cemented carbides. These new materials, composed of diamond and cemented carbide, showed a 50% larger fracture toughness and 10 times better wear resistance compared with conventional cemented carbides, and five times better machinability compared with diamond compacts. The diamond/cemented carbides are applicable to wear-resistant sliding tools such as centerless blades, work rests, and stoppers.