Electromagnetic heating metal phase diagram experimental method and experimental test tube

Abstract

The invention relates to the technical field of heaters and specifically relates to an electromagnetic heating metal phase diagram experimental method and an experimental test tube. According to the experimental method disclosed by the invention, a system is initiated, a sample heating temperature is set, whether a loader exists in a heating furnace is scanned by a single chip microcomputer, effectiveness of the loader is scanned by the single chip microcomputer, and an electronic component is prevented from being damaged by too large current. After all input signals are detected by the systemand are all normal, self check passes. After the self check passes, an instrument begins to formally output current to heat a sample, the temperature of the sample is collected by the system in realtime and is compared with the set temperature; when the temperature of the sample is lower than the set temperature, the system continues heating the sample; when the temperature of the sample is higher than the set temperature, the system stops heating the sample and begins cooling; meanwhile, a timing function is started, count down time is set according to need, and an operator is reminded to write down the temperature in the corresponding interval until an experiment is finished. According to the experimental method disclosed by the invention, the relationship between temperature and timein a cooling process is measured, an inflection point and a cooling platform are drawn in the cooling process, and an accurate phase change temperature can be obtained.

Description

Technical field [0001] The invention relates to the technical field of heaters, in particular to an electromagnetic heating metal phase diagram experimental method and an experimental test tube. Background technique [0002] Thermal analysis is an analytical method in physical chemistry and one of the basic methods for drawing phase diagrams. It is based on the principle that the phase change of a substance is accompanied by a thermal effect. When the melt (metal, alloy or compound) is uniformly cooled, if no phase change occurs, the temperature of the system will drop uniformly. If a phase change occurs during the cooling process, the temperature change of the system becomes unbalanced, and a horizontal line or turning point appears on the cooling (or heating) curve (temperature-time relationship curve). In physical chemistry experiments, the phase diagram of the binary alloy system is often obtained by making the step cooling curve of the sample. The system is gradually coole...

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Problems solved by technology

However, the fact is that for those who use this instrument for the first time, even if they are repeatedly reminded, their heating temperature will be much higher than the specified temperature, causing a large number of thermocouples to be burned out and scrapped every time;

[0007] 2. The two-component alloy phase diagram devices currently on the market are not only expensive, but also relatively complicated in design

When the mechanical parts are running mechanically, the noise is large, the wear is large, and the environment is polluted;

[0008] 3. The original equipment did not have a fast cooling program, which made the original plan that each group had to collect five sets of experimental data be compressed into two groups

[0010] 1. The thermal inertia of resistance heating is large, and it is difficult to control the temperature. It is easy to heat above the design temperature, causing the liquid paraffin to boil and the sample to deteriorate.

[0011] 2. If the heating is turned off in advance in order to control the temperature, it is easy to cause insufficient heating and uneven melting of the sample

However, after the heating is stopped, a temperature difference is formed between the sample and room temperature. Due to the increased temperature difference, the cooling rate of the sample per unit time may be relatively fast, causing the temperature of the sample to reach the phase transition point (freezing point) to drop before the phase transition temperature occurs. up

Supercooling occurs on the step cooling curve, and the accurate phase transition temperature cannot be obtained, resulting in a large error in the drawing of the phase diagram

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