Standardization of Shape Memory Alloys from Material to Actuator
On March 28th, 2023 a technical article outlining the roadmap for the standardization of shape memory alloys (SMAs) for use in actuators was published. Co-authored by Kinitics Automation, the article focuses on several material specifications and test methods that are seen as key to supporting the use of SMA-based actuators in commercial applications.
With the capability of generating large forces and doing significant work in a very robust, energy dense, and compact design, SMA provides a high value actuation technology for a broad range of commercial applications. Despite these proven benefits, their transition from prototype demonstration to widespread use in commercial applications has not reached full potential. The roadmap outlined in the technical article draws heavily from the medical sector experience where SMA’s enjoy widespread use and adoption in the medical applications. Rapid commercialization in this sector followed the industry adoption of ASTM standard F2063, a specification for SMA used in medical devices and surgical implants that was first published on November 10th, 2000.
In addition to the recently published ASTM standards (E3097 and E3098) that describe test methods to evaluate actuator and shape memory effect properties, a material specification that evaluates and controls the wrought material is needed. Work has begun under a ASTM Work Item on a new standard specification for wrought nickel-titanium based SMAs for actuation under the rational that, while there exists a broad range of potential applications for SMA actuators, their transition to production is hindered by a lack of accepted industry and regulatory certification standards. In addition to the standard specification, two new test methods covering constant torque thermal cycling and force controlled repeated thermal cycling are also being developed under ATSM Work Items. Next steps for the new standards under development, include relevant testing to establish or confirm requirements, finalizing drafts, balloting and publishing per ASTM guidelines.
