Conversion of conventional push-rod dilatometers for ultra-low thermal-expansion measurements is described. The method is based on the determination of the displacement of the probe-rod by ultra-precise dial-gage measurements by means of a laser-speckle technique. The movement of speckles created in space by the laser beam incident on an aluminum foil attached to the needle of the gage is observed for the measurements. It has been found that the sensitivity of the modified dilatometer is orders of magnitude higher than the existing LVDT approach.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Mechanical Engineering
- Electrical and Electronic Engineering