Exterior wall decoration is one of the important contents of building decoration. Its purpose is to improve the ability of the wall to resist various factors such as dust, rain, snow, freezing, and sun exposure, and together with the wall structure to meet the insulation , heat insulation, sound insulation, waterproof, landscaping and other functional requirements. Next Xiaobian will introduce to you the exterior wall decoration materials .
First, Portland cement
There are two types of Portland cement, namely type I Portland cement without mixed materials, denoted by code P·I; and limestone or grain with no more than 5% of cement quality during the grinding of portland cement. The blast furnace slag is referred to as type II Portland cement and is denoted by the symbol P·n.
1, Portland cement composition material
The Portland cement clinker is calcined to a part of the raw material with the appropriate ingredients. The resulting calcined calcium silicate is the main component of the sinter, which is called Portland cement clinker, or clinker for short. Clinker is the main component of various Portland cements, and its quality directly affects the performance and quality of cement products.
Mixed materials refer to those mineral materials that are added to the clinker and gypsum together with clinker and gypsum to increase cement production, reduce cement production costs, increase cement varieties, and improve cement performance, such as granulated blast furnace slag, limestone, and powder. Coal ash and pozzolanic mixed materials. Gypsum is a component used to adjust the setting time of cement. Natural gypsum can be used, and industrial byproduct gypsum can also be used.
2. Mineral composition of Portland cement clinker
A series of physical, chemical and physical chemical reactions (raw material drying, dehydration of HA's minerals, carbonate decomposition, solid phase reaction, clinker sintering, and clinker cooling) occur in sequence during the heating of the raw meal. material. The clinker is mainly composed of CaO, SiO2, A1203-%Fee0, four kinds of oxides, and the total amount is above 95%. They are shaped into mature material minerals through a series of complicated physical and chemical reactions. There are four main minerals of Portland cement clinker: tricalcium silicate (3CaO·Si02), dicalcium silicate (2CaO·Si02), tricalcium aluminate (3CaO·A1203), and tetracalcium aluminosilicate ( 4CaO·A1203·Fe203). During cement hydration, four mineral components exhibit different reaction characteristics.
3, mixed with Portland cement
In order to improve certain properties of portland cement, increase production and reduce costs, adding appropriate amount of mixed materials in Portland cement clinker, and grinding together with gypsum to obtain hydraulic binder material, known as blending Material of Portland cement. Portland cement mixed with mixed materials includes ordinary portland cement, slag portland cement, pozzolanic portland cement, fly ash portland cement, and composite portland cement. They are all part of the Portland cement series, with clinker as the main component and gypsum as a retarder. The difference between different types of cement is mainly due to the different types and quantities of the blended materials. The production of various silicate series cements mixed with mixed materials can produce different types of cement for the rational use of cement to meet the needs of various construction projects, increase cement production, reduce cement production costs, save energy, and improve the stability of cement Sex, reduce the heat of cement hydration, improve the anti-corrosion capacity of concrete, etc., make comprehensive use of industrial waste, reduce environmental pollution, and realize the ecologicalization of the cement industry.
Second, ordinary silicate pot cement
The hydraulic cementitious material made of Portland cement clinker, 6% by weight of mixed material, and appropriate amount of gypsum ground, known as ordinary portland cement (ordinary cement), code P.00 doping activity When mixing materials, the maximum mixing amount must not exceed 15%. It is allowed to use kiln ash not exceeding 5% of cement mass or non-reactive mixed material not exceeding 10% of cement mass.
Third, slag Portland cement
The hydraulic cementitious material made of Portland cement clinker, granulated blast furnace slag, and appropriate amount of gypsum is called slag Portland cement (slag cement), codenamed P.5.
IV. Pozzolanic Portland Cement
The hydraulic cementitious material made of a mixture of Portland cement clinker and pozzolanic material and an appropriate amount of gypsum is called pozzolanic portland cement (or pozzolan cement), codenamed P·P. The mixing amount of pozzolanic mixed materials in cement is 20% to 50% in terms of mass fraction.
V. Fly ash cement
The hydraulic cementitious material made of portland cement clinker, fly ash and appropriate amount of gypsum is called fly ash portland cement (abbreviated as fly ash cement), and code name P·Fo cement medium pulverized coal The ash content is 20% to 40% in terms of mass fraction.
Sixth, composite Portland cement
The hydraulic cementitious material made of Portland cement clinker, two or more kinds of mixed materials, and appropriate amount of gypsum ground is called composite Portland cement (referred to as composite cement), code P.C. The total mixing amount of mixed materials in cement should be greater than 15% by mass, but not more than 50%. In cement, it is permissible to use not more than 8% of kiln dust instead of mixed materials. The mixed material content of the mixed slag cannot be duplicated with slag Portland cement.
Seven, white Portland cement
1, white cement raw materials
White cement raw materials should be pure limestone, white I soil or calcite, kaolin, pyrophyllite or sandy cat soil with low iron content. Both raw material preparation and clinker grinding should be carried out without iron contamination. The fuel is preferably ashless natural gas or heavy oil; if pulverized coal is used, its coal ash content is required to be less than 10%, and the FeO content in coal ash is low. In order to ensure the whiteness of the cement, the whiteness of the gypsum used must be higher than the whiteness of the clinker. Generally, high-quality fibrous gypsum is used.
2, the chemical composition of white cement
The white cement clinker is still based on Portland cement clinker.
3, other varieties of white cement
White Sulphate Cement: White Sulphate Cement is mainly made of limestone and Al-Si ore (such as coke gemstone), plus appropriate amount of dolomite and a small amount of fluorite as flux, and coke as fuel, the block in the blast furnace It was completely melted, and after quenched with water, a pale blue slag was obtained. After drying, an appropriate amount of calcined gypsum and a small amount of quick lime were ground together to produce white sulfate cement. The cement has faster coagulation and hardening, high early strength, steady growth in late strength, strong resistance to carbonization, and no sanding on the surface. The disadvantage is that the hydration rate at low temperatures has declined.
White Cinder Slag Cement: White steel slag cement is obtained by grinding the white slag reducing slag with a proper amount of satin calcined gypsum. It can also be made by adding a suitable amount of white granulated blast furnace slag. This kind of white steel slag cement has early strength and quick set characteristics, 7d strength can reach about 90% of 28d strength, the disadvantage is that the early strength is low, the strength of cement is not stable enough, its advantages are low cost, strength can grow steadily, resistance Eroding is good.
Editor's summary: What are the exterior wall decoration materials introduced here? For more information, you can follow this site information.
Partition wall decoration kindergarten corridor wall decoration bedroom wall decoration partition wall what material balcony wall decoration
Carbide Thrust Block,Carbide Thrust Plate,Cemented Carbide Thrust Plate,Carbide Thrust Plate For Wear Parts
Zhuzhou Kerui Cemented Carbide Co., Ltd. , https://www.carbide-china.com