Abstract: A composite aluminum alloy plate for a case of an electronic product contains: a first aluminum alloy plate and a second aluminum alloy plate. The first aluminum alloy plate is made of first aluminum alloy material, and the second aluminum alloy plate is made of second aluminum alloy material. The first aluminum alloy material is selected from any one of 6XXX series aluminum alloy to 8XXX series aluminum alloy, and the second aluminum alloy material is selected from any one of 1XXX series aluminum alloy to 5XXX series aluminum alloy. The first and second aluminum alloy plates are stacked and compounded by hot rolling so as to produce the composite aluminum alloy plate having an external layer, an intermediate layer, and an internal layer. Thereafter, the composite aluminum alloy plate is laminated by cold rolling and is stabilized in a tempering treatment.

Abstract: A sprocket and chain assembly for bicycles is revealed. The sprocket and chain assembly for bicycles includes a bicycle sprocket and a bicycle chain. A contact part of the bicycle sprocket and a contact part of the bicycle chain in contact with each other are made of a multi-layer clad metal which is composed of a first metal and a second metal. The first metal has higher hardness and density than the second metal. A surface material for the contact parts of the bicycle sprocket and the bicycle chain is the first metal for providing sufficient wear resistance and ensuring service life of both the bicycle sprocket and the bicycle chain. Moreover, the lightweight design of the bicycle sprocket and the bicycle chain is achieved and sufficient structural strength is provided by the contact parts made of the multi-layer clad metal.

Abstract: A vapor chamber composed of a lower shell, an upper shell and a working fluid is revealed. The upper and lower shells made of metal composite plates are connected closely to form a vacuum sealed cavity which the working fluid is filled in. The metal composite plate includes a metal matrix and a copper layer bonded to a surface of at least one side of the metal matrix. The metal matrix includes stainless steel and an aluminum silicon carbide (Al/SiC) metal matrix composite. The copper layer of the metal composite plate is treated by stamping process to form a support member inside the cavity. Thus complicated, polluting and high cost etching process is no more required. Therefore the production efficiency is improved and the cost is reduced. The metal matrix of the metal composite plate provides sufficient structural strength.