Abstract: An impact feedback operation device includes a base member, an operation member having an operation part equipped with a touch sensor, an actuator having a shape memory alloy wire, a temperature sensor, a voltage sensor, and a processing unit. The processing unit determines an energization condition required for the shape memory alloy wire, depending on a detected temperature and a detected voltage. The operation part is fixed to the base member through an elastically deformable elastic portion.

Abstract: An impact feedback operation device includes a base member, an operation member having an operation part equipped with a touch sensor, an actuator having a shape memory alloy wire, a temperature sensor, a voltage sensor, and a processing unit. The processing unit determines an energization condition required for the shape memory alloy wire, depending on a detected temperature and a detected voltage. The operation part is fixed to the base member through an elastically deformable elastic portion.

Abstract: Disclosed is an acidic cleaning aqueous solution for aluminum and aluminum alloy and a process for cleaning the same, intended to execute acidic cleaning without using harmful fluoride and chloride ions.The oxidation-reduction potential of a cleaning bath is controlled to be at 0.5 to 0.8 V (vs. Ag-AgCl). The cleaning bath is obtained by diluting an acidic cleaning aqueous solution for aluminum and aluminum alloy to a predetermined volume. The acidic cleaning aqueous solution contains specified amounts of at least one of inorganic acids, Br.sup.- ions and oxidized metal ions, with the addition of a surfactant and oxidizing agent if necessary.It is thus possible to present a uniform etching effect irrespective of low temperature (below 60.degree. C.) without containing fluoride ions and chromic ions within the acidic cleaning aqueous solution. Br.sup.