초록 ▼

A process is described of preparing composite articles of aluminium or aluminium alloy suitable for superplastic forming by explosion welding two or more components together and heating the welded article to consolidate the bonds. The welds do not extend into areas to which a stop-off composition ha

A process is described of preparing composite articles of aluminium or aluminium alloy suitable for superplastic forming by explosion welding two or more components together and heating the welded article to consolidate the bonds. The welds do not extend into areas to which a stop-off composition has been applied and the article can be superplastically formed by passing a pressurized fluid into these stopped-off areas.

대표청구항 ▼

A process of forming a bonded composite article made of two or more components, at least one of which is made of a material having a protective surface layer and at least one of which is made of a material that can be superplastically formed, which process comprises applying a stopping-off material

A process of forming a bonded composite article made of two or more components, at least one of which is made of a material having a protective surface layer and at least one of which is made of a material that can be superplastically formed, which process comprises applying a stopping-off material to a discrete area of a first component, juxtaposing the first component with a second component so that the said discrete area lies between the first and second components, placing an explosive adjacent to one of the components, explosion bonding the first and second components together to form a composite article in which the components are joined together in areas to which the stopping-off material had not been applied and heat treating the composite article: (a) at a temperature at which diffusion bonding can occur for a time such as to increase the strength of the bond between the components and to partially inflate the stopped-off area while still maintaining superplastic properties of the superplastic component(s), and (b) in a step in which the temperature of the composite article is gradually increased from the said diffusion bonding temperature to a temperature at which superplastic forming can take place, the rate of the said increase in temperature not exceeding 3°C. per minute.