Effect of conditions of finish rolling of steel rod on mechanical descalability

摘要

The effects of position of specimens in coils of low carbon steel rod, laying temperature, cooling conditions, aging time, relative humidity and temperature on scale cracking and removal behaviour in bending tests of mechanical descalability have been studied. It was found that laying temperature has a larger effect on scale thickness than cooling rate. Thicker scale results in better descalability. Aging time under ambient conditions after rolling results in little systematic effect on descalability, but considerable variability is attributed to variability in ambient relative humidity. Aging under controlled humidity conditions showed that low humidity is beneficial to descalability and that aging for more than 5 days at ambient temperature has little further effect. Higher aging temperature with constant high relative humidity has a small, but beneficial effect on descalability.