Biomedical Engineering Reference
In-Depth Information
of mechanism transformation and got involved in exploring its
applications mostly from metallurgical point of view. They assume
the nonreversible transformation of martensite in steels.
In 1932, Swedish physicist Arne Ölander [32] observed that
the applied stress to gold-cadmium alloy could be taken off easily
(material returned to its original shape) by heating. In 1938,
scientiic research on CuZn revealed the temperature dependence of
nucleation and disappearance of martensite phase.
For the irst time, the concept of thermoelastic martensitic
transformation was introduced by Kurdjumov and Khandros
in 1949 [17]. Research on the thermally reversible martensitic
transformation of CuAl and CuZn alloys gives the reason to think that
this phenomenon could occur in a broader manner.
In 1951, Chang and Read used x-ray analysis [5]. They assumed
some rules of transformation mechanism in AuCd. They demonstrate
that the systems possessing shape memory effect could perform
work.
The irst signiicant research started in 1961 over the shape
memory alloys by the group of William Beuehler from Naval
Ordinance Laboratory, brought a breakthrough for the engineering
application. Beuehler's earlier research on intermetallic compounds
(for the nose cone Navy's missile SUBROC), which are supposed to
possess high melting point and impact resistance, showed that the
NiTi alloy reveal the best of it, with the satisfactory properties of
elasticity, malleability, and fatigue. The alloy was called NITINOL
in memory of the place where it was discovered (the acronym of
Naval Ordinance Laboratory was added to the NiTi intermetallic
compound's name). During the research on the NiTi alloy, Beuehler
made an observation related to the acoustic effect during cooling. In
1963, he conirmed the occurrence of the shape memory effect [2],
and for the irst time, this phrase was used to determine material
property [3].
Scientiic research carried out by Wang [48] shows that
the addition of the third alloying element, Fe or Co, to the main
composition NiTi had a strong inluence on the temperature of
transformation.
The irst application of shape memory alloys was introduced
by Raychem Corporation for pipe couplings in F14 jet ighters
[7, 38]. The temperature of transformation was so low that before
assembly, couplings were transported in liquid nitrogen, which
