A new sintering mechanism is revealed for copper powder sintered under the influence of an electrical field and a force field during the formation of microcomponents. Analysis of the microstructure and grain boundary evolution of the sintered samples showed that the disappearance of the interface at contact areas between particles is a continuous process which involves new grain formation and grain refinement during this innovative microsintering process. The densification process is therefore different from what is known in a conventional powder sintering process

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External electric field-activated sintering techniques have been widely investigated and applied for the forming of large-sized components. These techniques are, however, rarely utilized for the manufacture of miniature and microsized components. In this paper, a novel, coupled forming, and sintering method is reported, which has been used for the fabrication of microcomponents, wherein the loose powder is loaded directly into the die, followed by simultaneous electrical forming and electric sintering (named coupled multi-physics-fields activation). In the study, the gears with the module of 0.2 and the pitch diameter of 1.6 mm were formed from copper powder. The coupled multi-fields activations were enabled using a Gleeble-1500D thermal simulation machine. Sintered samples with a relative density of 97.20 % have been fabricated at a sintering temperature of 700 °C, heating rate of 50 °C/s, forming pressure of 100 MPa, while these parameters were applied cyclically. The study showed that the axial reduction of the samples increased rapidly with the increase of temperature during the sintering, while the external pressure was maintained. Based on the experimental observations, it can be concluded that the deformation of the particles resulted in an increase in, and then subsequent disappearance of, the interface areas among the particles, which feature plays a key role in the densification of the copper powder

The effective extension of tool life while maintaining machining quality is an important research topic in advanced machining and sustainable manufacturing. Cemented carbide is widely used as the tool material in different manufacturing processes, and it has various forms and work ranges. However, the internal flaw in the tool material can induce a micro crack which could result in the decrease of tool strength and toughness and affect the tool life. Improving the tool cutting performance, slowing down the tool wear, and enhancing production efficiency are the eternal themes of cutting tool research. This research focused on a P10 cemented carbide tool. The influences of the electromagnetic coupling field (TEMCP) on the carbide tool life and the maximum of tool force are investigated. The correlation analysis between the TEMCP parameters and the tool life index is conducted using SPSS. The experiment proves that the TEMCP can significantly prolong the cemented carbide tool life, and that the magnetic intensity is a dominant factor. The TEMCP enriches the field technology theory and provides technical support for the sustainable manufacturing and research and development of a high-performance tool with important scientific meaning and research potential.