Subject liquidus

The force and the period over which the force is applied determine the proportion of solidus and liquidus character. A letterpress ink is subjected to differing forces over differing periods of time and (since it is a mixture of viscous and elastic components) its solidus/viscous character will differ as it... 

Figure 34.23. Schematic setup of the hot tearing tests performed by Herfurth and Engler [29]. A thick plate of an A1 alloy is subjected to several heat sinks inducing a temperature distribution as indicated. After a thermal equilibrium has been estabhshed with a small hquid zone, acting as a stress concentrator, a tensile load is applied with a given crosshead speed and fracture goes from the bottom to the top. The sample is covered in the interesting area with a silica aerogel and the test is observed by an infrared camera. Note Tl means the liquidus temperature, Ts the solidus temperature, the eutectic point.

This paper is dedicated to the memory of Professor Frank H. Spedding, Iowa State University, who died on December 15, 1984 at the age of 82. It is especially appropriate to the subject of this paper because a fair fraction of his many scientific endeavors was devoted to the study of the rare earth metals—especially their preparation, properties and alloying behavior of the intra rare earth binary alloys. His contributions (along with his many collaborators) in this area include the first to prepare metallic Sm metal the determination of its unique crystal structure the discovery of the Sm-type structure in an intermediate alloy phase formed by a light and a heavy lanthanide the first to ascertain that the crystal structure of the high temperature phase was bcc and the first to show that there is no detectable separation between liquidus and solidus (< 1°C) in binary alloy systems of the lanthanide metals that have atomic numbers within four of each other. 

Only 45 s above liquidus (minimum allowed reflow time) was used for each reflow cycle, in order to limit the amount of time the board was subjected to the elevated temperatures. 

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