A support method for preventing sintering cracking of titanium-aluminum alloy liner compact

Abstract

The invention provides a supporting method for preventing sintered cracking of a shaped charge cover pressed blank of a titanium and aluminum serial alloy and belongs to the technical field of sintering control. By calculating the sintering shrinkage rate of a titanium and aluminum serial alloy material, a rigid supporting body structure can be designed reasonably, the dimension of the obtained rigid supporting body is consistent to a theoretical inner dimension of an obtained sintered blank after the shaped charge cover pressed blank is sintered, the shaped charge cover pressed blank can be supported sufficiently, cracking due to excessive deformation of the shaped charge cover pressed blank in the sintering process as a result of gravity and sintered cracking due to softening and collapsing are avoided, and the pressed blank sintering percent of pass is improved obviously. An inward pressure can be applied to the shaped charge cover pressed blank by burying sand, so that the bottom of the pressed blank can be promoted to shrink inward in the sintering process so as to further inhibit cracks as a result of non-synchronous sintering and shrinking in the pressed blank. Embodiments verify that the method can prevent sintered cracking of the shaped charge cover pressed blank of the titanium and aluminum serial alloy, and the sintering percent of pass of the pressed blank can reachover 99%.

Description

technical field [0001] The invention relates to the technical field of sintering control, in particular to a support method for preventing sintering cracking of a titanium-aluminum alloy liner mold compact. Background technique [0002] Petroleum perforating charge is a device used to break through the concrete and rock between the casing and the production layer to provide circulation channels for oil and gas. At present, most petroleum perforating bullets use a shaped charge structure, and the liner is a key component of the shaped charge structure. The production quality of the liner directly determines the effect of the perforating charge. The traditional drug-type cover is usually prepared by melting casting and hot isostatic pressing sintering. Low efficiency also increases production cost. Therefore, powder metallurgy near-net forming method is now mostly used to prepare thin-walled hollow conical parts of titanium-aluminum alloys. The method includes cold isostati...

AI Technical Summary

Problems solved by technology

However, during the sintering process, the collapse and deformation of the compact will eventually lead to cracking, which affects the processing size of the product and reduces the pass rate of the product

[0003] The sum of the mass percentages of titanium powder and aluminum powder in the raw materials used for titanium-aluminum series alloys is greater than 70%. The sintering temperature of the alloy is 1300-1600°C, and the melting point of aluminum is 660°C, which makes aluminum occur during the sintering process. Melting, existing in the whole body in the form of liquid for a period of time, resulting in softening of the green body, if no support is used or the support is too small, the green body will collapse and deform under the influence of its own gravity. At the same time, Due to the friction between the bottom of the green body and the hearth, the inward shrinkage of the bottom of the green body is difficult to proceed smoothly during the sintering process, resulting in the asynchronous shrinkage of the bottom of the green body and the shrinkage of the top, resulting in cracks on the inner wall of the green body; Large, so that the green body after sintering is suspended on the support body, and the outer surface of the green body will be cracked under the influence of its own gravity

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