Dilatometer measuring sample length during electrolytic processes - where change in sample length moves ferrite core inside search coil (CS 30.4.80)

摘要

A sample rod is located in a frame so the top end of the rod is free to move, and is in contact via an insulating coupling with a rod. On the top of this rod is a fused silica rod carrying a ferrite core, which moves inside a double coil when the length of the sample rod alters. The coil can be moved axially in a clamp assembly via a micrometer screw, so a zero point can be obtd. on a micro-ammeter at the start of measuring and recording the changes in length of a sample. The carrier parts of the device, and the moving rod are all made of a material with a coeffit. of thermal expansion of 1 x 10 power -7 to 5 x 10 power-6/deg.C. e.g. an Invar alloy (RTM). A nut prestresses rod in frame. For example, in electroplating; the hydrogenation of metals; or measuring the internal stress created in anodising.