玻镁板（Mgo Board）

玻镁板（Mgo Board） 玻镁板(Mgo Board) The concept of magnesium cement edit (1) different names and standardization of magnesium cement; Magnesium cement is a special kind of cement, because it was invented by French Sorel (Sorel) in 1867, so it is also called magnesium oxychloride cement. At the same time, it takes Magnesium Oxide as the main ingredient, it is customarily called magnesia cement. In many enterprises, according to it to Magnesium Oxide and magnesium chloride two kinds of magnesium compounds as the main raw material characteristics, also referred to as "double magnesium cement". Usually, people are accustomed to call the magnesite cementitious material, because his main raw material of light burned magnesia powder is calcined magnesite. Later, people used glass fiber to strengthen the magnesium cement to make inorganic composite materials, which is called inorganic glass fiber reinforced plastics. So far, magnesium cement has a new name, inorganic glass fiber reinforced plastic. So many names of magnesium cement, it is very confusing, as of now there is no name of a standardized, legal, unified, if called "magnesium oxychloride cement", so some do not use magnesium chloride as the magnesia cementitious material blending agent cannot be included. If called "magnesite cement" has its limitations, because the magnesia cementitious material can not try and try the calcined magnesite, dolomite powder ash. "Magnesite cement" cannot include dolomite lime cement. The prosperity of Haicheng Magnesite Factory "but if called" magnesium cement ", the concept can be broad. This can not only include magnesium oxychloride, magnesia cementitious material can also include the addition of magnesium chloride to other agents that can contain harmonic; calcined magnesite cement, can also be inclusive of calcined dolomite and magnesium cement. Therefore, it is appropriate to refer to magnesium cementitious material as "magnesium cement". The magnesium cement is collectively referred to as magnesium cement, which is intended to promote its name. (2) the concept of magnesium cement Is the use of magnesium cement calcined magnesite from light calcined powder or low temperature calcined dolomite the ash (the main component of MgO) for cementing agent, with six water magnesium chloride (MgCL2 - 6H2O) and water soluble magnesium salt as additive, adding water, formed by light burnt magnesia and six water chloride magnesium as the main raw material, and therefore, in general, refers to the magnesium oxychloride cement cement. The main component of hardened magnesium cement is formed by 5Mg (OH) 2 - MgCL2 - 8H2O and 3Mg (OH) 2 - MgCL2 - 8H2O phase consisting of Magnesium Oxide - magnesium chloride water three yuan compound salt crystallization phase, in addition, there is a part of Mg (OH) 2 gel. Magnesium cement can be hardened rapidly at normal temperature and pressure, forming a relatively brittle and artificial stone with high hardness. It can be processed into a variety of building materials and decorative materials by using this hardening and gelling property. It has broad application prospects. Artificial stone formed by magnesium cement hardened body similar to cement, with cementitious properties like cement, but its performance of conventional cement have great differences, different test methods, the two is not a concept. 2 development status of magnesium cement in China edit China's magnesium cement and its products have nearly eighty years of development history, as early as 1930s had the practice of making cement floors and walls using magnesium cement in building, and do a magnesium cement factory floor, but the path of development of China's magnesium cement and its product is not smooth, experienced a hazy understanding, a preliminary understanding and deepen the research into several stages, the development of norms, roughly as follows: 1, the initial period of magnesium cement Understanding and application of magnesium cement should be said in the Northeast China, because Liaoning is rich in magnesite, and from the practice that Magnesium Oxide and magnesium chloride solution after curing and hardening speed, without moisture curing, flexural strength and high compressive strength, high hardness, good wear resistance, but poor water resistance products, in the rain and wet weather products under the moist surface, and then covered with drops of water, even water flowing into a phenomenon, easy deformation, the reaction mechanism is not at all clear understanding, not on the phase structure and phase composition of products, so the performance of the master products are blind and contingency. No application of modifier, it can be said that understanding of magnesium cement is hazy, this period lasted nearly 30 years, the development is very slow. 2, comprehensive and in-depth research and application period In the "75" period, joint research by the former National Science and Technology Committee of the Chinese Academy of Sciences Qinghai Saline Lake Research Institute, Qinghai Building Materials Research Institute of Chinese Academy of Sciences, Shanghai Institute of ceramics, Chinese Academy of Sciences, Tongji University, Beijing Institute of geology, Beijing iron and Steel Institute, Northwestern University, Shenyang Institute of Metal Research Institute and other research institutions, and, after five years, costing tens of millions of dollars for, issued "the research and development of magnesium cement and its related 75-37-04-01, magnesium cement base and the characteristics of physical and chemical research", "75-37-04-02, the preparation process of magnesium cement, 75-37-04-03, magnesium cement products and Its Applications", "75-37-04-04, Magnesium cement trial "joint research, has made great achievements, such as the use of bischofite produced by Magnesium Oxide active magnesium cement, the magnesium cement system equilibrium and non equilibrium phase diagram, reveals the reason why magnesium cement poor water resistance, preliminary research on the variation of magnesium cement hardened products in use in the process, discovered the 518 crystalline phase has a variety of forms, using the technology of composite admixture, the gas rigid magnesium cement into the water resistance of magnesium cement, pointed out the research direction of hydraulic magnesium cement etc.. 75 scientific and technological achievements of the magnesium cement the level of our country in the international leading position, the application conditions of magnesium cement in the construction have been prepared using magnesium cement, magnesium cement concrete, lightweight aggregate concrete and porous concrete, the concrete has been used for the production of magnesium cement reinforced concrete load-bearing member glass fiber reinforced magnesium magnesium cement cement products, decorative materials and insulation materials. After entering 1980s, China's magnesium cement categories and products are more. In the building materials industry are: fire boards, fire protection decorative boards, building templates, non load partition board, movable room, building decoration components and lines, doors and windows, ventilation ducts, smoke exhaust roads and corrugated tiles. In the municipal sector are: manhole covers, garbage cans, etc.. In the machinery industry, there are packing boxes, Inorganic cable trays and so on. In agriculture, there are vegetables, greenhouse skeleton, granary and so on. The development of magnesium cement products to many types and wide functions. 3, enter the healthy development of the norm In twenty-first Century, magnesite industry has entered a new period of development, but the industry's lack of talent, small scale, backward technology, lack of strict product quality assurance system; management and optimization of magnesite market order have not been solved thoroughly. Especially the "75" scientific and technological achievements have not good in-depth to allow enterprises to digestion and absorption, quality of raw materials to ensure the light burning Magnesium Oxide bottleneck in the development of the industry is still in the boom, that magnesite appeared shoddy products listed, caused some adverse effects. In order to promote the healthy development of the industry, China Magnesite Industry Association was used to adjust the industrial structure of magnesite, magnesite in the industry to carry out the rectification, the implementation of industry access system, improve the industry threshold, clarify the importance of the establishment of quality management and quality control system. For the development of Scientific Outlook on Development guide Magnesite Industry, China magnesite Association pay close attention to personnel training, technical exchanges, must hold an annual meeting each year, the academic report is the annual meeting of the central issue of experts and technical exchanges, technical advice. At the same time, the widely publicized standards magnesite materials and products in the industry, after decades of efforts, China's Department of building materials, materials, metallurgy, machinery, chemical, fire and light from different field requirements issued a series of standards. It should be said that the national attention, industry and pragmatic work, make our country magnesite career into standardized and healthy development period. [1] Main properties of 3 magnesium cement edit (1) the common cementing material of air hardening, represented by general cement, is hydraulic, that is, it can harden in water. But magnesium cement is quite different from conventional cement. It is hard and hard to harden in water. This is a more prominent feature of magnesium cement compared with conventional cement. (2) multicomponent magnesium cement is a multicomponent, single light burned magnesium water is not hardened. It is a group of light burned magnesium or dolomitic lime powder, another component is a blending agent of magnesium salt, other components including water and modifier. (3) high heat release magnesium cement releases high heat when it is hardened. Its heat release amount is 1000~13500J/gMgO, the central temperature of the highest reaction system can reach 140 degrees C, and it may exceed 150 degrees C in summer. The hydration heat of ordinary cement is only 300~400J/g cement, and magnesium cement is 3~4 times of that of ordinary cement. (4) the strength of the steel, corrosive magnesium cement mostly magnesium chloride as a blending agent, containing a large number of chloride ions, steel corrosion is very strong. (5) high strength magnesium cement can easily reach 62.5MPa. The compressive strength can generally light burnt magnesia cementitious materials can reach more than 62.5MPa, most of which can reach more than 90MPa. In the light burnt magnesia, magnesium cement quality can be guaranteed the reasonable ratio of science and technology under the condition can reach about 140MPa. Experiments show that when the light burned magnesia powder and inorganic aggregate mass ratio is 1:1, the compressive strength up to 34MPa a day, the flexural strength of 9MPa. 28 days compressive strength of 142PMa, flexural strength of 26MPa. (6) high wear resistance, and its abrasion resistance is three times of ordinary Portland cement. We have Yongmei cement and conventional 32.5 Portland cement for each a piece of tile, together with the maintenance of 28 days of anti abrasion test, grinding length of 34.7mm ordinary portland cement floor tile, The ground brick made of light firing powder has a length of only 12.1mm, which is equivalent to 1/3 of cement ground brick, which is in conformity with the test abroad. Therefore, magnesium cement is particularly suitable for the production of floor tiles and other high wear-resistant products, especially abrasives, such as polished tiles, grinding blocks and so on. Haicheng Xingsheng Magnesite Factory (7) high temperature and low temperature, in all kinds of inorganic cementing materials, only magnesium cement at the same time, that is, high temperature resistance and low temperature resistance characteristics. The main component of light burning powder, MgO, is 2800 C, which is the first of all kinds of refractory used in Magnesium Oxide. Therefore, magnesium cement building materials products are generally resistant to high temperature characteristics, even if the composite glass fiber, but also fire-resistant more than 300 degrees C. Because of the fire resistance of magnesium cement, it is widely used in the production of fireproof boards. Magnesium cement is not only excellent in high temperature resistance, but also excellent in low temperature resistance. Because magnesium cement is mostly magnesium chloride as a blending agent, while magnesium chloride is antifreeze, chloride salt. Therefore, magnesium cement has a natural resistance to low temperature, so at low temperatures, magnesium cement products can also be produced as usual, without additional antifreeze. In general, resistant to -30 DEG C at low temperature. (8) anti bittern corrosion of magnesium cement is used for brine as conditioning agents (mostly magnesium chloride), that is to say it is a brine composition, so it is not afraid of brine corrosion, and also increase the strength in bittern. This makes it can overcome the shortcomings of ordinary cement and concrete products, for the bittern area. (9) the air stability and weatherability due to magnesium cement is gas rigid, in the final set only in the air which can continue to harden, which makes it have good air stability, the air is dry, the more stable it is. The results show that the compressive strength and bending resistance of magnesium cement products increase with age in dry air, and it is still stable until the age of two years. It is also proved that the strength of magnesium cement in dry air is continuously increasing. In addition, because of the high and low temperature resistance of magnesium cement, it is stable in high temperature climate and cold climate, and will not affect its stability due to climate change. It is weather resistant is also very good. (10) the conventional cement of low alkalinity fever corrosion of magnesium cement is far lower than that of any breed. It is tested that the pH value of the slurry filtrate fluctuates between 8~9.5, which is very low and close to neutral. Because the alkalinity of magnesium cement is very low, it is only alkaline, and the corrosion of glass fiber and wood fiber is very small. You know the GRC products with glass fiber reinforced plant fiber products, wood shavings, sawdust, cotton stalk, bagasse, peanut shell, rice husk, maize powder, wood fiber reinforced by heart, and the glass fiber and wood fiber are not alkali resistant materials, extremely afraid of alkali corrosion, high alkali corrosion they will lose strength. The cementitious materials lose enhancement effect. Therefore, conventional cement can not be reinforced with glass fiber and wood fiber because of high alkali. The magnesium cement has unique unique alkaline advantages in the field of GRC and fiber products in the field to show their talents, and this is it can become the main reason for inorganic glass fiber reinforced plastic. (11) the density of light and low density magnesium cement products is only 70% of that of ordinary silicate products. The density of its products is 1600~1800kg/ cubic meters, while the density of cement products is 2400~2500kg/ cubic meters. As a result, it has very low density. (12) rapidly solidified magnesium cement has the spontaneous quick coagulation property. Generally, when the agent is added, the strength of the mould can be reached by 4~8h. Its initial setting is 35~45min, final setting 50~60min, be equivalent to fast hard cement. The rapid solidification of quick hardening cement is formed by adding accelerating material, and the production process is complicated, while magnesium cement is a fast coagulation formed by the material itself. (13) good impermeability. The magnesium cement has a high degree of compactness after setting and hardening. The pores are much smaller than conventional cement. Therefore, it has a good impermeability after hardening, the water permeability coefficient is very low, and does not use anti permeability agent, and its hardened body can reach more than S25 impermeability mark. It is because of its good impermeability, decided it has a broad application prospects in the field of corrugated roofing materials etc.. (14) abrasive products high gloss with the same brightness, with a product in the preparation of magnesium cement of conventional cement material, and then compared the two gloss can be found, is a high magnesium cement product gloss than cement products. 4 advantages and disadvantages edit (1) advantages 1, generation of a wood magnesium cement material in the packaging industry, the building materials industry can be made of lightweight tile kiln instead of asbestos tile, tile, glazed tile, or made into building materials instead of some component of Portland cement products. 2. The production of energy saving and low consumption magnesium cement products is not only simple and convenient, but also requires thermal equipment such as kilns, dryers and so on. The energy consumption of production can be greatly reduced. 3, the use of safe, non-toxic, tasteless magnesium cement does not contain harmful substances, The product is non-toxic, tasteless and volatile, and has no irritation, and the use is very safe. 4, solid waste volume, high utilization rate due to high strength magnesium cement, when mixed with a large number of solid waste filler, it can still meet the strength requirements, therefore, magnesium cement products are generally mixed with fly ash and sawdust, straw powder, mixing amount of up to 60% 30%~. 5, the application field of application of a wide range of products, currently has nearly twenty magnesium cement products in a field of packaging materials, building materials, decoration materials, transportation facilities, aquaculture products, supporting products, refractory products, audio products, abrasives, wood furniture products to obtain a wide range of products have been developed. There are more than 100 varieties, new varieties still appear constantly. 6, good manufacturability, convenient use of magnesium cement products have good machinability, sawing, planing, nailing, drilling, carving, paste, very suitable for factory production and processing and installation site, very convenient to use. 7, low temperature molding, four seasons can produce magnesium cement, because of good resistance to low temperature can be as usual production, generally not affected, this is beneficial to extend the production period. 8, product has the advantages of simple process, easy production of magnesium cement solidification due to fast, not strict with the requirements of production conditions, general conditions can be engaged in the product processing, many products do not need large equipment, manual and semi manual can be engaged in the production, so it is easy to start the production of magnesium cement product, lower the threshold. 9. The production cost of the product is low and the profit is high. Because of the high strength, the magnesium cement can be mixed with a large amount of waste material, so that the amount of the material is reduced, the total cost is reduced, and the production cost is lower than that of ordinary Portland cement. (2) abuse 1, halogen halogen is in mg cement product is damp or ambient temperature is high, water or sticky stains appear tide and tidal water surface products, these stains with moisture or humidity increases, when the water drops or damp accumulation stains, it drips down from products, commonly known as "Tang chao". 2. Poor water resistance. The water resistance of the material is the ability to keep it stable for a long time or under the influence of water. The water resistance of magnesium cement is very poor, and its hardened body can gradually lose strength in water, and the strength loss rate can reach 60%~80%. 3, the warpage of magnesium cement product warpage was the most obvious, three-dimensional products generally irregular shape, or thickness of larger and smaller amplitude flat products, its deformation is small or the same shape, and large thin flat products the most easy to warp. The central part of the arch rises and the men bend. 4, it is the first expansion of the hardened crack: occurrence of micro cracks, micro cracks gradually widened and deepened, the product slowly crumbled into a pile of fragments, eventually, completely scrapped. The main technical performance of hardening crack: setting time particularly fast, large amount of heat release, rapid development of early strength, while the late strength is low, and with standard temperature cracks, especially after the water splitting into pieces, and the hardening Center for the powder, splitting into pieces, and the hardening center became powdery. No strength. 5, pan frost, white magnesium cement products wide frost, white generally more obvious 5 use of magnesium cement edit 1. for the production of building materials: fireproof board (magnesium plate), light partition, Magnesite covers, magnesite tile, ventilation pipe, activity room, greenhouse support etc.. 2. for the production of decorative materials: fire doors, imitation stone relief art decorations, flower pots, art fountain, large rockery, antique large door lion, trash, culture stone and brick art culture, railings, household or large combined granary etc.. 3. used in the production of packaging materials: pallets, electrical machinery, instrumentation, large wooden packing boxes, especially mechanical equipment, packaging boxes, etc.. 4. for the production of transport facilities: Highway shelters, police box, road guardrail, bridge parapet, lampposts etc.. 5. for the production of handicrafts: animal figures crafts, flower pots, wall, frame, urn, park chairs, Rome post, wood furniture, bird feeder, plate, box products, garden ornaments series etc.. 6. used in the production of chemical materials: desulfurization, Magnesium Sulfate, selenium and so on. 7., for the production of other products: Abrasives, biogas tanks, firecrackers, solid agent and so on.