Since non-standardized conditions resulted in poor repeatability and reproducibility of test results as well as failure to measure some of the powder contact angle during the powder contact angle measurement test, this paper studied the impact of such external factors on the powder contact angle test as compactness of the powder column, number of layers and height of the wrapped filter paper and the selection of dipping liquid. Following results were obtained:the compactness of the powder column remarkably influenced the discreteness of the powder contact angle, where the more stable the compactness was, the smaller discreteness we got;such external factors as number of layers and height of the filter paper wrapped at bottom of the glass tube and the selection of dipping liquid imposed direct impact on whether we could get results of the powder contact angle, especially to powders with greater grain size; powders with bigger grain size needed more layers of filter papers wrapped at the bottom; in order to get results of the contact angle of the powders smoothly, we needed to make the top surface of the wrapped filter paper at bottom of the glass tube above the liquid level and to select the polar liquid with non-zero dispersion component of surface energy parameter components.%针对矿粉接触角测定试验中条件非标准化导致的试验结果重复性差、复现性差,及部分矿粉接触角无法测得的问题,根据试验原理并结合试验现象,对粉体柱密实度、滤纸层数及其包裹高度、浸渍液体选择等外因对矿粉接触角试验的影响进行了试验研究.研究表明:粉体柱的密实程度对矿粉接触角的离散性影响显著,密实度越稳定接触角离散性越小;玻璃管底部滤纸包裹层数及包裹高度、以及浸渍液体的选择等外因,对能否测得矿粉接触角有直接影响,并且对粒径较大的矿粉影响尤为显著;矿粉粒径越大,玻璃管底部需要包裹滤纸层数越多;玻璃管底部包裹滤纸的顶面需高出液面,选择表面能参数分量中色散分量非零的极性液体,以确保顺利测出粉体的接触角.
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