Exploring structural phase transitions in Heusler Ni49Mn33.4In(15.6-x)Vx (x=0; 0.3; 0.5;1) alloys within the 8-400 K temperature range via T

We propose an in-depth investigation of structural phase transitions in Heusler Ni49Mn33.4In(15.6-x)Vx (x = 0, 0.3, 0.5, 1) alloys across a broad temperature range (8 - 400 K) using Thermal-Diffuse Scattering (TDS). These alloys exhibit a significantly reduced thermal hysteresis (~2.3 K) due to improved geometric compatibility between martensitic and austenitic phases, enhancing their potential for reversible magnetostructural transitions under cycling magnetic fields. Understanding the atomic-scale mechanism of structural phase transitions is essential for optimizing solid-state magnetocaloric cooling materials and improving their thermal and mechanical efficiency. Our study will utilize single-crystalline grains (~100 µm), eliminating ambiguities associated with powder-based methods and providing deeper insight into phase coexistence and structural evolution.