Abstract: There is provided a composite material having a composite film on a substrate, the composite film including a silver layer that contains carbon particles, wherein a crystallite size of silver of the composite film is 30 to 100 nm and Vickers hardness Hv of the composite film is 75 or more.

Abstract: A data relay apparatus has a plurality of conversion process parts installed therein and the plurality of conversion process parts are prepared for respective types of data items transmitted from a first data processing apparatus used as a data transmission source. The conversion process parts are software parts which convert data items of respective types. The data relay apparatus includes a data reception processing section which receives data transmitted from the first data processing apparatus, a data conversion processing section which determines a type of data received, retrieves one of the conversion process parts which is prepared for the data and starts the conversion process parts, and a data transmission processing section which transmits data converted by the conversion process part to a second data processing apparatus.