Development of an ultrasonic fatigue testing machine at high temperature up to 1000℃

研制了一种用于高温疲劳试验的超声波疲劳试验机。这台机器的工作速度可达1000℃。在进行高温超声疲劳试验时，必须注意温度对弹性模数、变幅杆设计等方面的影响。在本研究中，所有这些问题都得到了解决，并验证了所研制的机器的有效性。具体地，对锅炉用耐热钢和涡轮叶片用镍基单晶高温合金分别进行了650℃和1000℃的超声疲劳试验。结果表明，超声波疲劳试验与常规疲劳试验具有较好的一致性。

An ultrasonic fatigue testing machine for high temperature fatigue tests was developed. This machine can be operated up to 1000℃. In carrying out high temperature ultrasonic fatigue testing, careful attention must be paid to temperature effects on elastic modulus, horn design and so on. In this study, all of these problems were solved and validity of the developed machine was confirmed. More specifically, ultrasonic fatigue tests were conducted on heat resistance steel for boiler at 650℃ and on Ni-base single crystal superalloy for turbine blade at 1000℃. As the result, the ultrasonic fatigue testing show good agreements with conventional fatigue testing.