Mg3(PO4)2 cement is composed of 66.5 parts of metal oxide powder by weight, 24 parts of phosphate, 5 parts of retarder and 4.5 parts are mixed into a solidification component, while the metal oxide powder is dead burned magnesium oxide powder with purity greater than 90% and fineness less than 200 meshes, the phosphate is potassium dihydrogen phosphate, and the purity is greater than 98%, while the retarder borax is a technical product with purity greater than 98%, and the solidification component 2hpo4 is adjusted with K, Fine aggregate with fineness modulus of 2~3, and a mixture of river sand and quartz sand with maximum particle size of 4.75mm.

The preparation steps of the quick repair mortar are as follows: weigh various raw materials according to the above proportion, dissolve the K component 2hpo4 in the phosphoric acid retarder borax and magnesium cement in the mixing water to form a mixed solution, treat it into the residual curing agent of magnesium cement, mix mineral admixtures such as powder in the mixing kettle, enter the mixing kettle to mix the mixed solution, mix at a low speed for 30s, add fine aggregate, then mix at a low speed for 30s, and mix at a high speed for 90s, The mortar mixer is a planetary type mortar mixer. Its low-speed mixing speed is 135r/min, rotating around the sun 57r/min, high-speed mixing speed is 275r/min, rotating around the sun 115r/min, and the Mg3(PO4)2 cement based quick patching mortar with uniformly enhanced water resistance is obtained.

Mg3(PO4)2 cement is composed of 60 parts of metal oxide powder, 28 parts of phosphate, 6 parts of retarder and 6 parts of retarder measured by weight. The metal oxide powder is dead burned magnesium oxide powder with purity greater than 90% and fineness less than 200 meshes. The phosphate is potassium dihydrogen phosphate, a technical product with purity greater than 98%, and the retarder borax, a technical product with purity greater than 98%. The solidification component 2hpo4 · 3H2O is adjusted to K and fineness modulus is 2~3, Fine aggregate with a maximum particle size of 4.75mm.

All kinds of good raw materials shall be weighed according to the above proportion, and the preparation method of Mg3(PO4)2 cement based quick patching mortar with excellent waterproof performance shall be referred to Example 1.

The preparation steps of the quick repair mortar are as follows:

1) Weigh 5 portions of borax and 4.5 portions of K into 2hpo4, add enough water to fully dissolve them, and obtain mixed solution;

2) 66.5 portions of dead burned magnesia powder, 15 portions of silica fume and 15 portions of fly ash are poured into the planetary mortar mixer in turn, and the mixed powder is obtained by mixing at a low speed of 140r/min and 62r/min rotating around the sun for 5min;

3) The mixed solution can be added into the mixed powder at will. Rotate at 140r/min and rotate at a low speed of 62r/min for 30s around the day. Add fine aggregate. Rotate at 140r/min and rotate at a low speed of 30s and rotate at 62r/min around the day. Rotate at 285r/min and rotate at a high speed of 125r/min for 90 seconds to obtain Mg3(PO4)2 cement based quick patching mortar.

The above description of the embodiments is for the convenience of the skilled person and the person using the invention. It is obvious that skilled people can easily make various modifications to these embodiments, and the general principles described herein are applicable to other embodiments without performing creative work. Therefore, the invention is not limited to the above embodiments. According to the announcement of the invention, all competent field technicians should be within the protection scope of the invention without departing from the scope of improvement and modification.