Magnesium Phosphate Cement Mechanics And Research To The Influence Factors Of Water Resistance

This paper studies the effects of different additives on the structure and properties of magnesium phosphate cement by optimizing the experimental ratio and explores the hydration mechanism of magnesium phosphate cement.The results show that:1.P/M mass ratio of magnesium phosphate cement hydration has a decisive influence,magnesium oxide and potassium dihydrogen phosphate hydration reaction first occurred in the magnesium oxide particle surface,when the P/M mass ratio,the resulting water The product MgKPO₄·6H₂O less,magnesium oxide at this time play a role in supporting the skeleton.As the relative content of magnesia increases,the integrity of the matrix is destroyed,and the macroscopic properties deteriorate.Therefore,the best P/M ratio is 1:3.2.The water-cement ratio of magnesium phosphate cement equally significant.With the increase of water-cement ratio,the compressive strength of magnesium phosphate cement generally shows the first increase and then decrease,and reaches the maximum when the water-cement ratio is between 0.12 and 0.14.The water-cement ratio has little effect on the early strength of the magnesium phosphate cement stone,and has obvious influence on the later strength.Overall,the best water-cement ratio of 0.14.The introduction of borax on the structural performance of magnesium phosphate cement significantly.With the increase of the content of borax,the compressive strength of magnesium phosphate cement first increases and then decreases.When the content of borax is 11%,the compressive strength reaches the maximum.When the content of borax is more than 11%The compressive strength of magnesium cement decreases sharply.With the extension of age,the compressive strength of hardened body increases gradually.With the increase of the fly ash incorporation,the wear resistance of the magnesium phosphate cement tends to increase,and when the fly ash incorporation is 10%,its wear resistance is small,the wear resistance at room temperature it is good.The wear resistance of magnesium phosphate cement is better than that of ordinary silicate concrete.The reason may be that the magnesium phosphate cement contains a large amount of magnesium oxide particles that are not involved in the reaction,while the re-combustion magnesium oxide particles themselves have higher Wear resistance.5.The addition of citric acid provides a good acidic environment for the hydration reaction.Even when soaked in water,MgKPO₄·6H₂O can be continuously generated due to the conditions of the hydration reaction,and thus the adhesiveness is extremely strong Hydration products,so that the matrix will not loose,scattered skeleton,so that the matrix greatly enhance the water resistance.