The theory of the premelting phenomena in ionic crystals has been developed on the basis of the concept of heterophase fluctuation in the vicinity of their melting points. The size of the liquid-like clusters is estimated by the theory using the experimental specific heat value. Molecular dynamics simulations are also performed in NaCl and AgBr crystals to examine the ionic configuration in the premelting region. The structural features are discussed using the Lindemann instability criterion.

The precise magnetic-field-induced strain (MFIS) and magnetization of the martensite metallic compound Fe3Pt in a martensitic phase were studied in a pulsed magnetic field using the capacitance method at low temperatures down to 4.2 K, which is much lower than the martensitic transformation temperature TM=85 K. After zero field cooling, a pulsed magnetic field with a maximum frequency of 160 Hz was applied parallel to the [001]p axis. A large MFIS was measured. The value of the MFIS is ΔL/L=-1.7%. When the magnetic field was decreased, the recovery of the strain was observed. In the second applied field, a strain of about 0.6% was observed. This means that MFIS occurs even in short-pulse magnetic fields. MFIS was observed below 70 K. The largest strain was observed at 20 K. These results are almost the same as the MFIS in a steady magnetic field using a superconducting magnet.

A system for the simultaneous measurement of magnetization and magnetic strain, which is designed to be used in a pulsed magnetic field, has been developed. In this system, a capacitor on a sample is used and its capacitance changes with the displacement of a sample due to the strain on the sample in a magnetic field. Using this system, we have studied the magnetization and magnetic field-induced strain (MFIS) of the martensitic metallic compound Fe-31.2%Pd (at. %) at temperatures down to 80 K in martensite phase, which is much lower than the martensitic transformation temperature T_{M} =230 K. A substantial MFIS has been measured under a pulsed magnetic field with the time constant 6 ms, which corresponds to 80 Hz in frequency.

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