A piezo-thermal probe for thermomechanical analysis.

Thermomechanical analysis (TMA) is widely used to characterize materials and determine transition temperatures and thermal expansion coefficients. Atomic-force microscopy (AFM) microcantilevers have been used for TMA. We have developed a micromachined probe that includes two embedded sensors: one for measuring the mechanical movement of the probe (deflection) and another for providing localized heating. The new probe reduces costs and complexity and allow for portability thereby eliminating the need for an AFM. The sensitivity of the deflection element ((ΔR∕R)∕deflection) is 0.1 ppm∕nm and its gauge factor is 3.24. The melting temperature of naphthalene is measured near 78.5  °C.