A Direct Current Magnetron Sputtering Study of the Shape Memory Properties of Aluminum/Silicon Alloy Thin Films

Using dc magnetron sputtering, Al/Si films were made on surfaces made of fused quartz and silicon. It was carefully controlled that the films contained no more than 7 at.% silicon under ideal deposition conditions. This was done by changing the target's structure and adding silicon lines to it. This had to be done to get a good reading on how much silicon was in the plates. After being heated to 800°C and then cooled in very cold water, the thermo-elastic face-centered cubic structure changed into the flat crush test martensite. In Al/Si films with a Si content of 25.6%, this change took place. It looks like the shift in the opposite way was also thermoelastic. The several thermoelastic transitions that happened were caused by changes in temperature. Some Al-36 at.% Si coatings that were scraped off of a quartz substrate showed shape memory qualities when heated after being deformed. The coverings on these things were warped. Before the fabrication process began, a diaphragm-shaped film that stood alone was made and placed on a thin Si substrate. With a transformation hysteresis loop of about 12^OC and a temperature difference of only a few degrees from room temperature, this film has great hysteresis qualities. Another good hysteresis quality is a transformation hysteresis loop of about 12^OC. When heated and cooled several times, this diaphragm-shaped film showed a reversible tendency to expand, stretching as much as 0.08%.