The Electrothermomechanical Tester (ETMT) was developed by Instron and NPL and is located at The Ohio State University as part of equipment owned and operated by CAMM. The ETMT tests small rectangular geometries 40x2x1 mm in tension at a wide range of temperatures, including room temperature. The sample size can be varied within the limitations of load, resistance of the sample, and size of the grips. Room temperature testing must be performed with an external laser extensometer to accurately measure the gauge length. Room temperature tests to date have shown that as the feature size (grain size) decreases the data comes closer to mimicking that of traditional bulk tensile tests. The direct resistive heating capabilities and relatively small sample sizes allow for rapid and accurate temperature variations. Tensile, fatigue, creep, and heat treatment tests can all be reliably performed in either air or argon atmospheres and in displacement or load controlled conditions. Time between tests is decreased due to temperature ramp rates of 200oC per second, which are superior to that of a convection furnace. The ETMT is also capable of measuring the potential drop across the length of the sample, which allows for true stress/true strain measurements (constant temperature) and phase transformation identification.

Load Capcity: ±5kN
Temperature Rating: 300-1700oC (type R thermal couple range)
High Integrity Inert Gas Enclosure
Current capacity: 480 Amp max (dependant on material and cross section)
Displacement measurement devices:
Motor Encoder (1mm resolution)
Linear Encoder (0.1mm resolution)
Clip-on extensometer (1mm resolution)
External Laser extensometer (1mm resolution)
Model name and number: ETMT 8800 MkII

Ancillary Equipment:
Spot Welder (thermal couple attachment):
Miyachi Unitek Dual Pulse 125 power supply with 80A/EZ solder head

Example Results:

Relevant Papers published within CAMM       

None Currently Available – New area of research

Other References of interest available in the literature

1. Dary, F.-C., Roebuck, B., and Gee, M.G., Effects of Microstructure on the Thermo-mechanical Fatigue Response of Hardmetals using aw Miniaturised Testing Rig. International Journal of Refractory Metals & Hard Materials, 1999. 17: p. 45-53.
2. Griffiths, A., Nimno, W., Roebuck, B., Hinds, G., and Turnbill, A., A Novel Apprch to Characterising the Mechanical Properties of Super Martensitic 13Cr Stainless Steel Welds. Materials Science & Engineering A, 2004. 384: p. 83-91.
3. Roebuck, B., Gee, M.G., Miniaturised Thermomechanical Tests on Hardmetals and Cermets. Materials Science & Engineering, 1996. A209(1-2): p. 358-362.
4. Roebuck, B., Cox, D. and Reed, R., Measurement of the Temperature Dependence of g' Volume Fraction in a Ni-based Single Crystal Superalloy from Resistivity Measurements. Scripta Materialia, 2001. 44(6): p. 917-921.