V. Sampath

Bio: V. Sampath is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Shape-memory alloy & Microstructure. The author has an hindex of 13, co-authored 45 publications receiving 705 citations. Previous affiliations of V. Sampath include Ruhr University Bochum.

Influence of aluminium and iron contents on the transformation temperatures of Cu-Al-Fe shape memory alloys

Abstract: Copper based shape memory alloys have received much focus in recent times because of their good ductility, ease of production and processing and low cost. Earlier investigations have shown that ductility and other mechanical properties of the Cu-Al based shape memory alloys can significantly be improved by adding ternary elements such as Ni and Mn. While Cu-Al-Ni shape memory alloys have better thermal stability and higher operating temperatures, their practical applications are limited because of their poor workability. Cu-Al-Mn shape memory alloys on the other hand, have good ductility and workability, but their operating temperatures are lower. A similar approach is followed in Ni-Al alloys to overcome their brittleness by the addition of Fe. There is paucity of literature on the role of ternary addition of Fe to Cu-Al shape memory alloys. In the present work, therefore, the effect of aluminium and iron on the transformation temperatures has been studied. As the aluminium content increases the transformation temperatures decrease, while the ternary addition of Fe increases the transformation temperatures. The results are presented and discussed in detail in the paper.

Effect of Ternary Addition of Iron on Shape Memory Characteristics of Cu-Al Alloys

Abstract: The effect of alloying Cu-Al alloys with Fe on their transformation temperatures and shape memory properties was investigated by differential scanning calorimetry and bend test. It was found that the minor additions of iron resulted in change of transformation temperatures and led to excellent shape memory properties of the alloys. Since the transformation temperatures are high, they are an ideal choice for high-temperature applications.

Effect of In-Situ TiB2 Particle Addition on the Mechanical Properties of AA 2219 Al Alloy Composite

Abstract: Aluminium alloy AA2219 was reinforced with TiB2 particles introduced in-situ by the saltmetal reaction technique. The microstructural examinations of the composites clearly reveal the formation of TiB2 particles with a hexagonal morphology. The addition of TiB2 particles results in increased mechanical properties, such as 0.2%YS, UTS and hardness. The improvement in mechanical properties is correlated to the microstructure.

Identification of Quaternary Shape Memory Alloys with Near‐Zero Thermal Hysteresis and Unprecedented Functional Stability

Abstract: Improving the functional stability of shape memory alloys (SMAs), which undergo a reversible martensitic transformation, is critical for their applications and remains a central research theme driving advances in shape memory technology. By using a thin-film composition-spread technique and high-throughput characterization methods, the lattice parameters of quaternary Ti-Ni-Cu-Pd SMAs and the thermal hysteresis are tailored. Novel alloys with near-zero thermal hysteresis, as predicted by the geometric nonlinear theory of martensite, are identified. The thin-film results are successfully transferred to bulk materials and near-zero thermal hysteresis is observed for the phase transformation in bulk alloys using the temperature-dependent alternating current potential drop method. A universal behavior of hysteresis versus the middle eigenvalue of the transformation stretch matrix is observed for different alloy systems. Furthermore, significantly improved functional stability, investigated by thermal cycling using differential scanning calorimetry, is found for the quaternary bulk alloy Ti 50.2 Ni 34.4 Cu 12.3 Pd 3.1 .