Analysis of the data obtained from liquid metal diffusion experiments conducted on the MIR space station

Recent liquid metal diffusion experiments onboard the MIR space station have led to the proposal that suppression of g-jitter may change the temperature dependence of the diffusion coefficient from a square law to a linear dependence. It has also been claimed that the diffusion coefficients obtained under isolation mode are significantly lower than their non-isolated counterparts. A thorough reanalysis of the original data leads to three principal findings: (i) a linear temperature-dependence does not emerge when all available diffusion data obtained on MIR in the isolation mode are considered in the analysis. This finding suggests that the D∝TD∝T relation that was shown previously for a number of dilute alloy systems may simply arise because very limited numbers of data were considered for analysis for each system; (ii) the measured diffusion coefficients obtained with g-jitter suppressed are not reproduced in two replicated experiments; and (iii) the diffusion coefficient values are not consistently below the corresponding non-isolated microgravity data. These facts suggest there is an uncontrolled source of experiment variation that is much stronger than the effect of g-jitter on the experiments. On the basis of these new findings, it is proposed that the results from the liquid metal diffusion experiments conducted on MIR do not support the conclusions drawn.