Michigan State University

Gm Global Technolgoy Operations, Inc.

University of Michigan

David S Grummon

Yang-Tse Cheng

Anita Miriam Weiner

John Andrew Shaw

Michael K Lukitsch

Wangyang Ni

Leonid Charles Lev

Yang T Cheng

Yijun Zhang

This invention discloses a method, using pure niobium as a transient liquid reactive braze material, for fabrication of cellular or honeycomb structures, wire space-frames or other sparse builtup structures or discrete articles using Nitinol (near-equiatomic titanium-nickel alloy) and related shape-memory and superelastic alloys. Nitinol shape memory alloys (SMAs), acquired in a form such as corrugated sheet, discrete tubes or wires, may be joined together using the newly discovered joining technique. Pure niobium when brought into contact with nitinol at elevated temperature, liquefies at temperatures below the melting point and flows readily into capillary spaces between the elements to be joined, thus forming a strong joint.

Manufacture of shape-memory alloy cellular materials and structures by transient-liquid reactive joining

This invention discloses a method, using pure niobium as a transient liquid reactive braze material, for fabrication of cellular or honeycomb structures, wire space-frames or other sparse builtup structures or discrete articles using Nitinol (near equiatomic titanium-nickel alloy) and related shape-memory and superelastic alloys. Nitinol shape memory alloys (SMAs), acquired in a form such as corrugated sheet, discrete tubes or wires, may be joined together using the newly discovered technique. Pure niobium when brought into contact with Nitinol at elevated temperature, liquefies at temperatures below the melting point and flows readily into capillary spaces between the elements to be joined, thus forming a strong joint. A series of diagrams of the interface at various stages of brazing is illustrated by FIG.

Manufacture of shape memory alloy cellular materials and structures by transient-liquid reactive joining

A method for producing a plurality of thin film actuators is disclosed. The method includes depositing a film of a shape memory alloy material onto a polyimide film to form a shape memory alloy construction. The shape memory alloy construction is strained from 2 to 8%. Post processing is conducted on the shape memory alloy construction after the step of imparting a 2 to 8% strain. This post processing can be the deposition of additional layers of the slicing of the actuators. Various shape memory metal actuators are disclosed.

Prestrained thin-film shape memory actuator using polymeric substrates

A method for forming a two-way shape memory surface includes thermomechanically training a shape memory alloy under substantially constant indentation strain. Thermomechanical training includes removeably securing an indenter to a surface of the shape memory alloy in its martensite phase, so that an indent is formed in the surface. The shape memory alloy is then heated to its austenite phase while the indenter is secured thereto. The shape memory alloy is then quenched to its martensite phase while the indenter is secured thereto. After thermomechanical training, the shape memory alloy surface exhibits a first indent depth when in its martensite phase, and a second, different indent depth when in its austenite phase. Also disclosed herein is a method for forming one-way and two-way reversible surface protrusions on shape memory alloys.

Two-way shape memory surfaces

A self-healing tribological surface comprises a shape memory material. The self-healing tribological surface can be used for recovering a scratches and/or indentations in the surface. Processes for recovering scratches or indentations generally comprises forming a shape memory material onto the surface; scratching or indenting the surface; and heating an area about the scratch or indentation, wherein a depth of the scratch or the indentation decreases after heating as compared to the depth prior to heating.

Self-healing tribological surfaces

A material and method for adhering at least two materials that includes the step of interposing at least one intermediate layer between the two materials and associated adhesion material. The materials to be adhered exhibit at least one characteristic dissimilarity and the intermediate material interposed contains at least one shape memory alloy, the shape memory alloy capable of exhibiting superelasticity.

Metallic-based adhesion materials

A material and method for adhering at least two materials that includes the step of interposing at least one intermediate layer between the two materials and associated adhesion material. The materials to be adhered exhibit at least one characteristic dissimilarity and the intermediate material interposed contains at least one shape memory alloy, the shape memory alloy capable of exhibiting -superelasticity.

The present invention discloses various embodiments of a thin film fluid control system (,) for controlling fluid flow through tubular conduits (,). The system is designed such that a shape memory alloy (,) is transformed between austenitic and martensitic phases to constrict or open the tubular conduit as desired.

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East Lansing, MI, United States of America

David S Grummon