An aqueous suspension for producing porous metallic structures comprises 2-49 vol % of a mixture of at least one chemical compound comprising a metal atom, wherein said at least one compound is solid at room temperature, has the form of a powder, and is suspended in water, and 10-9) to 0.1 mol of a surfactant per mol of said chemical compound comprising a metal atom. The aqueous suspension is part of a foam and/or is part of an oil-in-water emulsion, comprising 30-90 vol % of a lipophilic phase, said lipophilic phase not comprising a polymerizable compound.

The application discloses a preparation method for an aluminum alloy cavity casting filled with special-shaped foamed aluminum. The preparation method includes: preparing special-shaped foamed aluminum in a first mold by adopting a powder metallurgy foaming method; fixing the special-shaped foamed aluminum coated with the soldering flux in a second mold after the special-shaped foamed aluminum is coated with soldering flux; and casting by using molten aluminum alloy. According to the preparation method for the aluminum alloy cavity casting filled with the special-shaped foamed aluminum, the overall strength of the casting can be improved while the wall thickness of the casting is reduced to meet the requirement that the overall quality of the casting is not increased.

Vehicle structural components and additive manufacturing methods for forming the components are described. The structural components incorporate hydrogen storage materials for use in conjunction with hydrogen fuel cells in electric-powered vehicles such as unmanned aerial vehicles. The hydrogen storage materials can be in the form of a 3D printed metal foam that includes a metal hydride and an inert structural metal. The material can exhibit a very low weight density able to store hydrogen in a low pressure solid-state form at a high energy density. The structural components that carry the hydrogen storage materials can be exchangeable components of a vehicle, and the vehicle can be refueled by merely exchanging an exhausted component for a replacement component that is fully-charged with hydrogen.

A preparation method of copper foam includes coating copper paste on a release film to form a coating sheet with a thickness of 50-200 m on the release film, peeling off the release film to obtain a copper foam preform after drying the release film with the coating sheet, and performing a glue discharging process on the copper foam preform and sintering the copper foam preform to obtain the copper foam having a thickness of 30-120 m and having a porosity of 50-80%. The thickness of the copper foam is reduced, which ensures a balance between the porosity and a structural strength of the copper foam, so the copper foam has a good water absorption performance, and a heat dissipation performance of the copper foam is effectively improved.

Provided is a hydraulic actuator shell and a preparation method. The hydraulic actuator shell comprises a foam metal sandwich composite pipe, a foam metal sandwich flange and a foam metal sandwich end cover; the foam metal sandwich composite pipe is connected with one end of the foam metal sandwich flange, and the foam metal sandwich end cover is connected with the other end of the foam metal sandwich flange; the foam metal sandwich composite pipe comprises a first metal pipe layer, a first foam metal layer and a second metal pipe layer sequentially arranged from inside to outside; and a first bonding interface among the first metal pipe layer, the first foam metal layer and the second metal pipe layer is a metallurgical bonding interface. The hydraulic actuator shell is used for improving compression resistance, corrosion resistance and vibration and noise reduction capabilities of the hydraulic actuator shell.