零电阻现象和迈斯纳(Meissner)效应表明,超导体在发生正常态——超导态转变时电磁性质有显著的变化,由此可测定其临界温度T_c。超导材料临界温度的测量之最大困难是需要深低温工作,由此而引起了一系列低温技术上的问题,这些问题往往成为T_c测量的主要影响因素。一、测量装置及步骤目前临界温度测量的方法有电阻法、电感法和比热法等。我们的测量用的是电阻法。其特点是相对来说较简便。电阻法是根据当超导样品进入超导态时电阻变为 The zero-resistance phenomenon and the Meissner effect show that the superconductor has a significant change in the electromagnetic properties when the normal state-superconducting state transition occurs, and thus the critical temperature T_c can be measured. The biggest difficulty in measuring the critical temperature of superconducting materials is the need for deep and low temperature work, which causes a series of low temperature technical problems, which often become the main influencing factors of Tc measurement. First, the measuring device and steps The current critical temperature measurement methods are resistance method, inductance method and the specific heat method. We measure the resistance method. Its characteristics are relatively simple. Resistance method is based on when the superconducting sample into the superconducting state resistance becomes