Effects of Arsenic, Antimony and Tin on Strength, Recrystallization Temperature and Snoek Peak of Alpha Iron

Abstract

Synopsis:
Effects of arsenic, antimony and tin on strength, recrystallization temperature and Snoek peaks of alpha iron were investigated. It was found that the increase in tensile strength caused by cold drawing became layer in the order, arsenic, tin and antimony addition. Effect of arsenic on the recrystallization temperature of alpha iron was not observed, on the contrary, antimony and tin affected the recrystallization temperature and it rised about 90°C. Changes in tensile strength and in electrical resistivity at liquid nitrogen temperature after aging the alloys quenched from 950°C were also investigated. The changes assumed to be due to precipitation were found in the alloys bearing more than about 0.25 atomic per cent antimony and tin, but were not found in the alloys containing less than 0.045 atomic per cent of antimony and 0.094 atomic per cent of tin, and less than 0.38 atomic per cent of arsenic.
The internal friction peaks owing to carbon and nitrogen were investigated by using the alloys containing about 0.25 atomic per cent arsenic, antimony and tin. In addition to the usual carbon and nitrogen peaks, abnormal peaks were observed on high temperature side of the usual peaks. Activation energies of the abnormal peaks were determined as 19.1 kcal/mol in Fe-As-N, 19.2 kcal/mol in Fe-Sb-N, 200 kcal/mol in Fe-As-C, 21.5 kcal/ mol in Fe-As-C, 21.2 kcal/mol in Fe-Sb-C, and 22.5 kcal/mol in Fe-Sn-C.