Impulse-pressurzing sintering furnace

Abstract

The invention discloses an impulse-pressurizing sintering furnace. The impulse-pressurizing sintering furnace comprises a sintering furnace and an impulse-pressurizing device. The impulse-pressurizingdevice comprises an impulsator, an impulse converter, a servo valve, a servo oil cylinder, a force sensor, and a sensing signal transmitter. The impulsator is connected with the impulse converter. The servo valve is connected to an opening of the servo oil cylinder. The force sensor is connected with the sensing signal transmitter. The impulse converter, the servo valve and the sensing signal transmitter are all connected with a sintering controller. The sintering furnace comprises a furnace body. The furnace body is of a cylinder type. A mold is arranged in the middle position of the furnacebody. A sintering area is arranged inside the mold. The impulse-pressurizing sintering furnace has the beneficial effects that because plasma pulse current sintering is conducted on a material to besintered by adopting an impulse current generator, and the servo oil cylinder is controlled by the servo valve, the upper pressing rod and the lower pressing rod are impacted in opposite directions and pressurized; pressure is in closed-loop control; pressure on the upper pressing rod and the lower pressing rod are adjusted automatically; and the sintering temperature and sintering time needed bythe material to be sintered can be lowered.

Description

technical field [0001] The invention relates to the field of sintering and pressing equipment, in particular to a pulse pressure sintering furnace. Background technique [0002] Sintering is the core link in the preparation process of inorganic materials such as ceramics. During the sintering process, the material forms unique physical and chemical characteristics such as crystal structure, particle size, morphology, dislocations, and defects, so that the material has unique properties. The heating of the traditional sintering furnace relies on the heating element to transfer heat energy to the heated object through convection, conduction or radiation to reach a certain temperature. The heat is transferred from the outside to the inside. The sintering time is long and it is difficult to obtain fine grains. Pulse sintering is a new type of sintering method in recent years. The main feature of this technology is that a DC pulse current is applied to the electrode to generate ...

AI Technical Summary

Problems solved by technology

The heating of the traditional sintering furnace relies on the heating element to transfer the heat energy to the heated object through convection, conduction or radiation to reach a certain temperature. The heat is transferred from the outside to the inside. The sintering time is long, and it is difficult to obtain fine grains.

Pulse sintering is a new type of sintering method in recent years. The main feature of this technology is that a DC pulse current is applied to the electrode to generate discharge plasma instantaneously, and the surface activation effect of the pulse current and the self-heating of the particles is effectively used to achieve ultra-fast sintering of the material. Densified sintering greatly shortens the sintering time and lowers the sintering temperature, but the pulse current has strong directionality and polarity, which leads to uneven distribution of properties of the sintered material along the direction of the current and electric field, which affects the use of the material

Studies have shown that the pressure provided by the current sintering equipment is constant pressure. Under constant pressure, it is difficult for particles to slide and rearrange, and it is difficult to discharge pores. During the sintering process, "hard agglomeration" is easy to occur between particles, which easily leads to uneven microstructure. Therefore, the degree of densification of the sintered body and the improvement of mechanical properties are restricted. Moreover, the shrinkage of the powder and the densification of the material during the sintering process cannot be grasped in time, thus restricting the sintering of high-performance materials.

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