Strain-Detecting Composite Materials

A composite material comprising:

• a structural material;
• and
• a plurality of particles of a ferromagnetic shape-memory alloy embedded in said structural material;
• wherein said ferromagnetic shape-memory alloy changes crystallographic phase from austenite to martensite and changes magnetic phase in response to a predefined critical macroscopic average strain of said composite material.

A method of forming a composite material for sensing a predefined critical macroscopic average strain, the method comprising:

• providing a structural material in powder form;
• providing a shape-memory alloy having an austenite crystallographic phase, wherein said shape-memory alloy changes crystallographic phase from austenite to martensite in response to said predefined critical macroscopic average strain of the composite material;
• changing a size and shape of said shape-memory alloy to thereby form a plurality of particles;
• and
• combining said structural material and said plurality of particles of said shape-memory alloy at a temperature of from about 100° C. to about 700° C. to thereby form said composite material including said plurality of particles embedded in said structural material.

A composite material comprising:

• one or more layers of structural material;
• one or more layers of a shape-memory alloy;
• wherein each said shape-memory alloy layer is bonded to an adjacent structural material layer;
• and
• further wherein each said shape-memory alloy layer changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of said composite material.

A composite material comprising:

• a structural material;
• and
• a shape-memory alloy coating bonded to at least a portion of said structural material;
• wherein said shape-memory alloy coating changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of said composite material.