Mechanism analysis of magnesium phosphate cement by pyrophyllite under high temperature
The high-temperature resistance of magnesium phosphate cement(MPC)as an inorganic adhesive for strengthening and repairing building structures has attracted significant attention.In this paper,a pyrophyllite compound magnesium phosphate cement(P-MPC)was prepared.The high-temperature resistance of this mate-rial was analyzed through mechanical properties,mass loss rate,microscopic observation,and phase analysis.Results indicate that with increasing pyrophyllite content,the compressive strength retention rate of MPC grad-ually in creased at elevated temperatures.At 800 ℃,the strength retention rate of MPC with 12％pyrophyllite content was 20％,exceeding 6％of the blank control group.Phase composition analysis revealed that the de-composition of hydration product struvite was a key factor leading to the decrease in compressive strength of MPC.Thermogravimetric analysis indicated that the mass loss rate of MPC decreased gradually with increasing pyrophyllite content.Backscattered electron spectrometer(BES)analysis of the microstructure and elemental composition of the blank control group and the experimental group with 12％pyrophyllite content at 200 ℃ and 800 ℃ showed that the pyrophyllite maintained good integrity with MPC at high temperatures,indicating that this silicate material can effectively combine with MPCthereby improv its high-temperature resistance.
pyrophyllitemagnesium phosphate cementhigh temperature resistancebackscattered electron spec-trometer
万方数据
维普
