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Isothermal compression tests were conducted on A100 steel using a Gleeble 1500 thermal simulator at a temperature range of 900–1,200°C and strain rate range of 0.001–3 s−1. Results show that the A100 steel has higher strength than the Aermet 100 steel at high temperatures. Constant values, such as A, α, and n, and activate energy Qwere obtained through the regression processing of the stress–strain data curves under different strains. A set of constitutive equations for A100 steel was proposed by using an Arrhenius-type equation. The optimum processing craft ranges for A100 steel based on the analysis of the hot working diagram and deformation mechanism are as follows: temperature range of 1,000–1,100°C and strain rate range of 0.01–0.1 s−1. The average grain size within this working range is 7–22.5 μm.

The method of measuring mixed radon and thoron daughter concentrations during and after sampling is discussed and a versatile computer program for analyzing observed data of radon and thoron daughters has been written based on a mathematical technique using a matrix and weighted least squares calculation. The program is also suitable for calculating the concentrations of radon daughter from the total alpha spectroscopy data during and after sampling. A set of optimum time intervals is recommended for measuring the concentrations of mixed radon and thoron daughter.