The “Creep Test” is performed on an alloy sample to determine its physical characteristics at typical component operating temperatures. In very simple terms, a sample is heated to a material dependent stable temperature between 300°C and 1200°C. A load is then applied to the sample to exert a longitudinal force on the grain structure of the alloy. The sample is maintained in this state for the period of the test or until the component ruptures. During the test, data is continuously monitored and recorded to qualify the stability of the temperatures, loading and sample extension.
It is important to maintain tight control of the temperature across the entire sample with 0.2 degrees centigrade being typical for the sample uniformity tolerance. To achieve this many furnaces employ highly accurate control devices with three zones of heating. Tests may run for many months and occasionally years, it is important therefore that control systems are designed to accommodate power fail and abort strategies which will allow tests to be continued after unplanned interruptions.
Large creep laboratories may have several hundred furnaces, carrying out simultaneous testing of samples. The results from the tests form part of the audit trail of data for the eventual components and for convenience many users rely on communicating control systems to provide automation to the process of data management:
- Isolated thermocouple inputs
- Easy adjustment of Setpoint
- Power fail and recovery routines
- Long term process stability
- Measurement of “creep” and detection of sample break
- Digital communications and Data management solutions
6100A / 6180A Paperless Graphic Recorder 
6180 AeroDAQ Graphic Recorder 
3500 Advanced Temperature Controller and Programmer 
