Formed body of Cu—Al—Mn-based shape-memory alloy and method for producing same

A formed body, comprising:

• Cu—Al—Mn-based shape-memory alloy comprising a screw portion,
• wherein the screw portion has an Hs/Ho ratio of 1.1 or more when measured in a cross section including an axis of the screw portion for Hs and Ho,
• wherein Hs is an average Vickers hardness of a surface layer portion of the screw portion, and Ho is an average Vickers hardness of a central portion of the screw portion.

A method of manufacturing a formed body of Cu—Al—Mn-based shape-memory alloy comprising a screw portion, the method comprising:

• forming a screw portion having superelasticity by plastically working at least a portion of a raw material for the formed body with form-rolling in a state that a crystal structure is an A2-type structure, to obtain a formed raw material;
• and then,
• heat treating the formed raw material so as to convert an A2-type crystal structure in the formed raw material into an L21-type crystal structure.