Ni-Mn-Ga alloys exhibit supelastic and magnetic shape memory effect as discussed in class. Two other important properties of these alloys are the magnetocaloric effect and a negative magnetoresistivity. A) What is the magnetocaloric effect and negative magnetoresistivity? What is their practical significance? B) How are these effects being used in commercial applications? (you can use any reference on science direct or other data bases to answer this part. Cite your refernces clearly.) C) The mechanical behavior of these alloys is shown below. Estimate the modulus and tensile strength for 0%Dy and compare it to NiTi. D) The addition of the rare earth element Dy to these alloys is important in improving the mechanical properties. Plot the variation of approximate strength and ductility as a function of Dy content. What would be the optimum Dy content? E) Note also the Curie temperature (Tc) data for various Dy additions. What is the significance of this variation of Curie temperature?
