A Simple and Direct Method for Local Temperature Measurement and its Applications to Materials Evaluations

A technique utilizing chemical reagents for direct measurement of temperature at a local area and its engineering applications

“…The major steps used in the temperature measurement are listed as follows [16][17][18]: (1) A number of chemical reagents having different melting points were selected, which had been ranked in descending order in terms of their melting points, as shown in Table 3. The difference in the melting point between two consecutive reagents was around 5 • C. (2) The reagent which had the highest melting point was contacted with the measurement area.…”

“…1 and 2 [16]. Figure 1 shows the result of Valeramide (melting point was between 102 and 104 • C in catalogue).…”

“…Figures 3 and 4 show the results with l-Valine ethyl ester hydrochloride (whose melting point is equal to that of Valeramide in catalogue) and 2,4-Dimethylbenzoic acid (whose melting point is equal to that of N -Phenylglycine in catalogue) [16]. Both were free from problems of use and thus selected in place of Valeramide and N -Phenylglycine, respectively.…”

“…If the melting points of three different volumes of the reagent were approximately same, i.e., it was verified that the melting point did not depend on the volume of the reagent, the reagent was judged to be able to apply to the present method (see Ref. [16]). …”

“…[16], chemical reagents being applied to the temperature measurement were selected based on the following criteria: (1) The chemical reagent having melting point which can be introduced in the present method, was selected from a catalogue. (2) The selected reagent was investigated to determine whether it was safe for use from the Material Safety Data Sheet (MSDS).…”