with moveable lid
Heating stage (module) for elevated temperature experiments, with moveable lid for SEM in-situ examination. Metallurgical and materials science studies benefit from specimen heating in the SEM. Dynamic observations of phase transitions and other microstructural changes with respect to temperature can be informative for materials research and failure analysis. Using specialized equipment, dynamic gas reactions can be studied. The effect of re-crystallisation can be observed using the combination of specimen heating and electron backscattered diffraction (EBSD).
This substage (or "module") for heating experiments (room temperature to 1 050 degrees C) was mainly designed for the use in a SEM. It is clamped to the SEM stage just like a large specimen. The module comes in different shapes - they depend upon the available space around the specimen stage of the individual SEM for which it was made.
The module is suitable for corrosion experiments, and heating under gas or vapor. (NO Oxygen, NO Water) A needle valve at the vacuum feedthrough flange allows fine controlled "bleeding" of gas or vapor into the heating chamber, during the heating process. This small chamber can be closed by a motorized "lid" during the heating experiments under aggressive gas atmosphere, to protect the inside of the SEM. The cover will be opened again after completing the high temperature experiment in humid or gas atmosphere (see small inserts to the right), to inspect the surface of the specimen after heating.
If no gas is flowing, heating can also be done with the "lid" open, to observe the surface changes.
The center piece of this module is an encapsulated ceramic resistance heater. A flat metal cylinder serves as a specimen platform or holder; it may have all kinds of useful shapes - flat, or cup-shaped in the middle. Disk shaped specimens up to 25 mm diameter can be held down with small tungsten springs. The special heater does not produce electrical fields, which may distort the electron image.
The vacuum flange and attachment kit are in the shipment volume.
please make sure, BEFOR starting your experiment, that ALL components and gases etc. can work together without causing unexpected reactions. Materials used are: Tungsten, Molybdaenum, AL2O3.
The PID-temperature controller (usually equipped with a PC interface) pilots the temperature according to the physical parameters, required for the experiment. After an initial "learning"-routine, which is only done once, the heating rate can be selected. The controller finds this experiment temperature following a time/temperature-ramp without oscillations. Alternatively, the heating controller can also work by individual commands from the operator, changing the current in the heater and observes the changes on the specimen surface from step to step.
RT to 300, 500, 800 or 1 050 degrees, depending upon the required design. Various methods of attaching the specimen, according to your requirements.
Attaching the Module to the SEM Stage
The heating module is mounted to the SEM stage like a "large specimen". Typical SEMs for this version of the heating module are the whole Hitachi line, Stereoscans, Tesla, and a few others. Please let us know the type of your SEM.
Heating Under Gaseous Environment
Some SEMs allow viewing under "poor vacuum" conditions or with several Torr of water vapor. The 300 and 500 degree versions work at full atmospheric pressure at air, and in vacuum likewise. Higher temperatures should be done in the "VP" (= "Variable Pressure") modus of the SEM, or under vacuum. This module goes one step beyond this: certain environment may be created by admitting gases to the small subchamber of the heater. (NO Oxygen, NO Water) This gas inlet is controlled by a very precise needle valve, attached to the vacuum feedthrough at the SEM chamber wall. A fine stainless steel capillaryfeeds the gases into the heater chamber. The small heater chamber can be closed under vacuum with a motorized mechanism. Even strongly corrosive gases may be used while the cap of the heater chamber is closed.
Dimensions: Approx. 65 mm x 55 mm x 38 mm. The structure of this module is shaped so that it will never touch the chamber wall when opening the stage door. The furnace is lined with several layers of reflective, high temperature resistant sheet metal. For thermal isolation, the whole structure rests on sharp tips. This point contact, together with the shielding, keeps heat dissipation into the stage mechanics at bay.
- Micromanipulators (Prober-Modules) with integrated heating platforms: 300, 500 or 800 degrees C. Probers with 1 µm or tenth µm resolution, number of probers varies over a wide range from simple to very luxurious.
- "Cryo-Stages" (Liquid Nitrogen or Helium)
- "Cryo-Module" as a Substage (Liquid Nitrogen)