The core principle of second-hand power compensation DSC is to dynamically compensate for the thermal effect difference between the sample and reference material by independently controlling their temperatures. The working process can be divided into the following key steps:

-Dual heating system and temperature monitoring: The sample cell and reference cell are each equipped with independent heaters and temperature sensors, which are managed by two control circuits. A circuit is responsible for regulating the base temperature according to a preset program (such as linear heating/cooling); Another circuit dynamically adjusts the power of the compensating heater by monitoring the temperature difference between the two tanks in real time, ensuring that the sample and reference material are always at the same temperature.

-Dynamic compensation of thermal effect: When the sample undergoes endothermic reactions (such as melting or phase transition), the system automatically increases the heating power on the sample side to offset the heat loss; If the sample releases heat (such as crystallization or oxidation), reduce the compensation power. During this process, the instrument directly records the change in compensation power, forming a DSC curve.

-Signal output and analysis: The difference in compensation power directly reflects the heat flow rate of the sample, and through calibration, parameters such as enthalpy change and specific heat capacity can be quantitatively analyzed. For example, in the study of ordered disordered transition in alloys, the position and area of characteristic peaks can be used to determine the phase transition temperature and energy changes.

The measurement steps and usage precautions for second-hand power compensation DSC are as follows:

1、 Measurement steps

1. Sample preparation: Weigh 5-10mg of the sample, and evenly spread the powder sample in the crucible to avoid local overheating; The size of the block sample should not exceed 3mm in diameter and 2mm in height; for viscous or liquid samples, a special crucible (about 20mg) should be used. When the testing temperature is below the boiling point, a sealed dish can be used, and when it is above the boiling point, a high-pressure dish should be used.

2. Instrument calibration: Regularly calibrate the temperature and enthalpy with standard substances (such as indium and tin), check the integrity of the insulation layer, and prevent thermal drift from affecting the measurement results.

3. Parameter setting: Select the appropriate temperature range, heating rate, and atmosphere environment based on the characteristics of the sample.

4. Start testing: Place the processed sample into the DSC furnace, start the program, and monitor the changes in the DSC curve in real time.

5. Data processing: Analyze the peak shape and phase transition temperature in the DSC curve, and calculate relevant thermodynamic parameters.

2、 Precautions for use

1. Sample requirements: Ensure that the sample is dry and pure, and avoid impurities interfering with the measurement results.

2. Dosage control: Accurately weigh milligram level samples to save samples and reduce testing costs.

3. Equipment maintenance: Keep the furnace body and sample chamber clean and free of residue that may affect testing.