Abstract: Since the traditional “Binary Alloy Phase Diagram” has long been blamed for its poor operability, inadequate accuracy and heavy environmental pollution, effort is made to use low-melting material to prepare the solid-liquid phase diagram. By aid of kryoskopy in the making of cooling curve, online acquisition of temperature data and the synchronous display of cooling curve are realised by applying Bakerman temperature measuring device through burning experiment. The new method gives an excellent performance by successfully increasing the temperature accuracy from the past 0.2℃ to the current 0.001℃ and the experimental relative error decreases from 3% to 1.5%. Besides, it is characterized by easier operability, smaller dosage of chemicals, shorter experimental time, high safety and produces lilttle or no pollutants and emission, so it can well substitute the original binary alloy phase diagram experiment.