|INFLUENCE OF PULSED MAGNETIC TREATMENT ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF M42 HIGH SPEED STEEL TOOL|
|发表期刊||ACTA METALLURGICA SINICA
|摘要||Magnetic treatment of tools is a novel method to increase tool life in which the tool is magnetized before cutting or the cutting is performed in a magnetic field. The method has many attractive features, such as short treatment time and no pollution. However, this approach has not been widely applied yet, since the mechanism of magnetic treatment of tools is not clear and treatment results are affected by many factors. Therefore, it is important to study the mechanism ofmagnetic treatment of tools. This work aims to study the influence of pulsed magnetic treatment on microstructures and mechanical properties of M42(W2Mo9Cr4VCo8) high speed steel, which is a typical tool material which contains high amounts of cobalt. So it can show a stronger magnetism in the process of pulsed magnetic treatment. Changes of dislocation configuration, carbide distribution and microstructure before and after magnetic treatment were characterized by TEM and laser scanning confocal microscope. Moreover, Rockwell hardness and micro-hardness were measured to quantitatively investigate the influence of magnetic treatment on the mechanical properties. Results showed that after pulsed magnetic treatment the lattice of material was distorted, the carbide was precipitated, and the microstructure and crystalline grain were refined. The changes of microstructure led to changes of mechanical properties,of which the Rockwell hardness and micro-hardness were significantly increased. The maximum increase of Rockwell hardness was 2.9 HRC. Ultimately, the strengthening mechanisms of high speed steel were analyzed based on dislocation theory. It was shown that the subjected force of dislocations due to themagnetic treatment could overcome the centripetal restoring force and the Peierls stress of dislocations. Therefore, dislocations proliferated by the Orowan dislocation strengthening mechanism, and dislocation density increased. The dislocation configuration determined from TEM micrographs was in good agreement with the discussion of dislocation mechanisms.|
|关键词||Pulsed Magnetic Treatment
High Speed Steel
Ma, LP. INFLUENCE OF PULSED MAGNETIC TREATMENT ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF M42 HIGH SPEED STEEL TOOL[J]. ACTA METALLURGICA SINICA,2015,51(3):307-314.
Ma, LP.(2015).INFLUENCE OF PULSED MAGNETIC TREATMENT ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF M42 HIGH SPEED STEEL TOOL.ACTA METALLURGICA SINICA,51(3),307-314.
Ma, LP."INFLUENCE OF PULSED MAGNETIC TREATMENT ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF M42 HIGH SPEED STEEL TOOL".ACTA METALLURGICA SINICA 51.3(2015):307-314.