A review of high-temperature experimental techniques used to investigate the cohesive zone of the ironmaking blast furnace

The softening and melting (S&M) under load test is widely used as a laboratory-scale routine test to investigate the behaviour of ferrous burden materials in the cohesive zone (CZ). However, it has been more than 30 years since the last comprehensive review and over that time, operational conditions in large, high-production blast furnaces (BFs) have changed substantially. This review provides a summary and critique of current laboratory methods and practices used to evaluate the behaviour of ferrous materials in the CZ, focussing on the various configurations and operating conditions employed for the S&M under load test. Moreover, the review proposes and argues for a more integrated approach to S&M analysis for research, one which promotes a more comprehensive understanding of ferrous burden behaviour in the CZ region and which, in turn, enables the development of more robust, routine tests for the purpose of material comparisons and prediction of BF performance.