Magnesium carbon brick performance due to the different firing conditions will be big changes, Japan black asaki sowing grinding company technical personnel to study the mechanism of the performance of magnesium carbon brick change, based on graphite content of 8% low graphite magnesium carbon brick, by changing the firing time, examined the magnesium carbon brick thermal shock resistance performance, matrix tissue structure and the change of the distribution.

The sample was made of 8% scale graphite and 92 electrofused magnesium sand, plus 1% 99 metal aluminum powder, reduced and burned for 10h and 30h at 1400℃, and then the thermal shock resistance and tissue changes of the sample were investigated.In the heat-shock resistance test, the test block was impregnated in 1600℃ of iron water for 90s, and then water-cooled for 30s, and circulated for three times to compare the cracking of the appearance and section of the test block.The microstructure of the matrix was observed using FE-SEM, EDS.

After the section of the sample after the heat shock resistance test was observed, it was found that the reduced sample after 30h produced obvious cracking and poor heat shock resistance.The micrograph of the distribution of aluminum, magnesium, silicon and calcium in the sample matrix burned after 30h showed that the original micropowder of magnesium spinarefied, except for the presence of silicon and calcium.This indicates that the positive secondary binding in the substrate, coupled with the high impurity content, encourages the sintering of low melting materials, which leads to the rising elastic modulus and the reduced thermal shock resistance.