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The influences of 2.5wt% Mn addition on the microstructure and mechanical properties of the Cu-11.9wt%Al-3.8wt%Ni shape memory alloy (SMA) were studied by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and differential scanning calorimeter (DSC). The experimental results show that Mn addition influences considerably the austenite-martensite transformation temperatures and the kind of martensite in the Cu-Al-Ni alloy. The martensitic transformation changes from a mixed 1 1 1 β β +γ ′ ′ → transformation to a single 1 1 β β′ → martensite transformation together with a decrease in transformation temperatures. In addition, the observations reveal that the grain size of the Cu-Al-Ni alloy can be controlled with the addition of 2.5wt% Mn and thus its mechanical properties can be enhanced. The Cu-Al-Ni-Mn alloy exhibits better mechanical properties with the high ultimate compression strength and ductility of 952 MPa and 15%, respectively. These improvements are attributed to a decrease in grain size. However, the hardness decreases from Hv 230 to Hv 140 with the Mn addition.

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In this study, a simple Arduino-based experiment was designed to examine the movement of the object on an inclined plane and to define the kinetic friction coefficient. The experimental data on the movement of a small wooden block on the inclined plane formed from the hardwood was gathered with the help of an ultrasonic distance sensor. On the plane inclined at different angles, the wooden block was allowed to shift into its own position to obtain position-time curves. The acceleration of the object and then the kinetic friction coefficient were determined experimentally. The position-time curves obtained are in the expected character and the friction coefficient value is in the expected value range. Hardware and software are sufficient to examine movement on an inclined plane, and therefore a laboratory can be adapted to the context of teaching and learning.