When working in automotive R&D, awareness of how various materials act at ambient temperature as well as normal operating temperature is important. Many original equipment manufactures have unique temperature requirements that all components need to achieve, for example: -30oC to 80oC. However, engine and transmission components get considerably hotter. It is extremely important to subject the material to these temperatures during testing to understand their performance.
Non-ambient Metals Tensile Testing
THE CHALLENGE
In order to determine the material's performance at high temperatures, it is critical that the temperature of the material is carefully controlled when the desired temperature is reached. For auxiliary parts or components, the temperature requirement will not be as high when compared to the material within the engine block, which will be considerably hotter and can be closer to the melting point of the material which could cause failure.
THE Solution
3119-600 Series environmental chambers can accurately control the temperature from -150oC up to 600oC (-240°F to 1110°F) making them suitable for all types of materials within the engine and transmission assemblies. Alternatively, the 1200°C (2200°F) Model SF-16 three-zone resistance furnaces have a split construction design that facilitates fast and easy loading of a pre-assembled load string. Adjustable stainless steel latches keep the furnace halves locked together during use, but are then easily opened once testing is complete. The temperature soak time can be automatically set in Bluehill® Universal and once complete the test will start. Alternatively, utilizing TestProfiler you can have different temperatures under different loading conditions during the same test.
THE CHALLENGE
The complete stress-strain curve is important because it shows not only the maximum stress and strain a material can handle, but also important properties such as stiffness and yield (where the material becomes completely deformed), and ultimately, how the material will behave in use. Therefore, it is critical to determine the strain during high-temperature testing.
THE solution
There are several choices for extensometry, depending on your requirements and the type of furnace that you have. If the furnace has a port in the side, then a side entry extensometer can be used, these typically have long ceramic arms with the body of the extensometer outside of the temperature. Alternatively, if it is a closed type furnace, a vertical mechanical extensometer such as the W-6183 type is effective.