Heating holder guidelines
If you plan to use heating holders for in-situ experiments, we require your careful review and compliance with the following guidelines.
1. Include in your proposal target temperature and all phase diagrams of material with those of the tantalum furnaces and tantalum and/or molybdenum washers. Eutectic melting or bonding to the furnace body can occur at much lower temperatures than expected.
2. Holders are individually marked with the maximum temperature displayed on the specimen rod. Do not exceed this marked maximum temperature. It is easy to overshoot target temperature, so approach with caution.
3. Pre-schedule time for technical training and assistance by NCEM staff, especially if you are an infrequent or first-time user.
4. Heating holders are extremely delicate and must be loaded and unloaded with great care. Please seek help if you are unclear about any steps in the procedure.
5. The water recirculator must always be turned on for target temperatures above 500C.
6. If specimens are not self supporting, copper grids are generally adequate to 500C. For target temperatures above 500C, molybdenum grids are required. Gatan G-1 high temperature epoxy remains intact at temperatures in excess of 1000C.
7. The tantalum hex screw ($200 ea.) and tantalum washers ($20 ea.) are expensive to replace. If you drop these accessories on the floor, please find them immediately or ask someone under the age of 40 for help in locating them.
8. Use of heating holders for vacuum heat treatment of specimens is strictly forbidden.