Evaluation of the Validity of Crystallization Temperature Measurements Using Thermography with Different Sample Configurations

Abstract

We describe further progress of a previously reported novel crystallization temperature (T x) measurement method applicable for small sample sizes. The method uses thermography and detects T x as a change in emissivity of thin film amorphous alloy samples. We applied this method to various sample configurations of Pd–Cu–Si thin film metallic glass (TFMG). The validity of the detected T x was determined by electrical resistivity monitoring and differential scanning calorimetry (DSC). Crystallization temperature can be detected in all sample configurations; however, it was found that the magnitude of the detected change of emissivity at T x depended on the sample configuration. This emissivity change was clear in the absence of a higher emissivity material. The results suggest that this method can achieve high-throughput characterization of T x for integrated small samples such as in a thin film library.

Combinatorial search for Ti–Ni–Hf high formable shape memory alloys

“…The distance between the sample and the IR thermography was set at 0.5 m. The resolution in this case is 0.33 mm, which is sufficient for measuring the temperature of a 1 mm square alumina window. However, in a previous study, 20) when the alumina area on the substrate was large, the high IR radiation from alumina was a factor in the temperature error. Therefore, a Ti-Ni-Hf thin film with lower emissivity than alumina was deposited over the entire substrate to reduce the effect of IR radiation from alumina.…”

High-Throughput Characterization Method for Crystallization Temperature of Integrated Thin Film Amorphous Alloys Using Thermography

“…Previously, this method was demonstrated on plane thin film samples of Pt-Si, 21) Pd-Cu-Si, 22) and Ni-Nb-Zr thin film amorphous alloys. 25) Furthermore, the two-way martensitic transformation temperature of Ti-Pd-Ni thin film shape memory alloys was also detected by the same method.…”

“…Previous research studies have suggested that the method using thermography could be applicable to such libraries. [21][22][23] In this work, the high-throughput characterization of T x for thin film libraries was carried out, considering the previous results reported in ref. 21.…”

“…21. First, the configuration of the new thin film library was determined, in order to eliminate the influence of IR radiation from alumina 22) and including reference areas for temperature measurements. A homogeneous composition thin film library with this configuration was then fabricated and its T x was measured to confirm the validity of the proposed method.…”

High-Throughput Measurement Method for Time–Temperature-Transformation Diagram of Thin Film Amorphous Alloys

“…The thin film sample surface is monitored by thermography and the measured thermography indicates ''apparent temperature (T a )''. The apparent temperature is related to sample emissivity " as 15,16) T a ¼ " " 0…”