The property of black lead

40 people, span of atomic of the carbon in same network layer is 1. 42A. Belonging to 6 brilliant is, provide complete layer shape cleavage. Cleavage face is given priority to with molecular key, weaker to molecular appeal, reason its are natural but buoyancy is very good. Black lead is qualitative soft, black gray; Have fat feeling, can pollute paper. Hardness is 1 ～ 2, increase its hardness to be able to be added to 3 ～ along what perpendicular direction follows foreign matter 5. Specific gravity is 1. 9 ～ 2. 3. Below isolation oxygen condition, its melting point is in 3000 ℃ above, be most be able to bear or endure lukewarm mineral one of. The pure black lead in nature is done not have, often contain the impurity such as Si02, A1203, Fe0, CaO, P2O5, Cu0 among them. These impurity constant with the mineral form such as quartz, pyrite, carbonate appears. In addition, still have the aeriform share such as water, bitumen, CO2, H2, CH4, N2. Because of the analysis of this pair of black lead, except determine outside fixed carbon content, still must determine at the same time volatilize the content of cent and ash content. The craft character of black lead basically decides the crystallization form at it. The black lead with crystallization different pattern is mineral, have different industrial value and use. On industry, differ according to crystallization configuration, natural black lead cent is 3 kinds. 1. Black lead of compact crystallization shape calls black lead of compact crystallization shape lump black lead again. This kind of black lead is crystal and clear crystal is macroscopical. Grain diameter is more than 0. 1 millimeter. Crystal is arranged desultorily, show compact lump construction. This kind: The characteristic of black lead is grade very tall, contain carbolic quantity to be 60 ～ commonly 65 ％ , amount to 80 ～ sometimes 98 ％ , but its plasticity and satiny sex are not as good as scale black lead. 2. Crystal of black lead of scale black lead submits scale form; Deteriorate below the pressure of high strenth and this is become, have the branch of large scale and fine scale. The characteristic of ore of this kind of black lead is grade not tall, be in commonly 3 ％ of 2 ～ , or between 25 ％ of 100 ～ . It is nature in but one of ore with best buoyancy, choose more through be being ground more can get concentrate of high grade black lead. Of this kind of black lead but buoyancy, lubricity, plasticity all compares other type black lead advantageous; Its industrial value is the accordingly greatest. 3. Black lead of character of concealed of concealed crystalloid black lead calls noncrystalline black lead or earthy record black lead again, the crystal diameter of this kind of black lead is less than 1 micron commonly, it is the aggregate of microcrystalline black lead, below the electron microscope only ability sees brilliant body. The characteristic of this kind of black lead is the surface submits earthy form, devoid burnish, lubricity is poor also. Grade is higher. 80 ％ of general 60 ～ . A few is as high as 90 ％ above. Ore is optional the gender is poorer. Black lead because its are special structure, and have following special quality: 1) high temperature resistant model: The melting point of black lead is 3850 ± 50 ℃ , boiling point is 4250 ℃ , although calcination of electric arc of classics superhigh temperature, the loss of weight is very small, hot coefficient of expansion is very small also. Black lead intensity rises along with temperature and strengthen, when 2000 ℃ , black lead intensity raises one times. 2) electric, thermal conductivity: The conductivity of black lead is compared general metalloid mine is 100 times taller. Thermal conductivity exceeds the metallic stuff such as steel, iron, lead. Coefficient of thermal conductivity lifts along with temperature and reduce, fall in extremely high temperature even, black lead becomes adiabatic system. 3) lubricity: The lubricant function of black lead depends on the size of black lead scale, scale is larger, coefficient of friction is smaller, lubricant performance is better. 4) chemical stability: Black lead has good chemical stability below normal temperature, ability acid, alkali resistance and be able to bear or endure of organic dissolvent corrode. 5) plasticity: The tenacity of black lead is good, but the chip with very small the year's harvest. 6) heatproof shake sex: What black lead can withstand temperature when be used below normal temperature is acuteness change and do not send destroy, when temperature is choppy, the bulk change of black lead is not big, won't produce crackle. Natural black lead is mixed with lump black lead scale black lead is best, use is the most extensive. Our country has not discovered field of extensive lump black lead, black lead of scale black lead and concealed crystalloid all has bigger field, formed the base of large-scale exploitation. Natural black lead has a lot of good quality, apply extensively at national economy consequently departmental door, it is especially in industry of metallurgy, mechanical, electric equipment, chemical industry receive wide application. Black lead is had those who highlight is high temperature resistant and be able to bear or endure the property of microtherm, coefficient of expansion is very small, volume is steady, because this can resist the change of urgent cold urgent heat, of black lead high temperature resistant when property and general metal differ to lift when temperature, it is not to tend bate, and its intensity instead heighten. Black lead is the good conductor of heat and report, its conduct heat function and electric function and most metal are about the same, but have its characteristic again, general metal lifts when temperature when, coefficient of thermal conductivity also lifts subsequently, and the coefficient of thermal conductivity of black lead is contrary, when temperature is elevatory, its coefficient of thermal conductivity drops instead. Below extremely high temperature, black lead tends insulation condition, because this is below superhigh temperature condition, the heat proof quality of black lead is very reliable. The plasticity of black lead and lubricity win application on industry already, scale is larger, coefficient of friction is smaller, scale black lead is the accordingly most slippery, lubricity is best, take second place of black lead of compact crystallization shape, lubricity of earthy record black lead is poorer. Black lead is the super material of chemical industry, its chemical stability is very outstanding, it is acid-proof, alkali resistance, anti-corrosive, special place is had in chemical industry. Black lead still is the moderator with admirable atomic reactor, make the utility of black lead entered a new historical level, to make admirable moderator, the extract craft of black lead got further progress, because this black lead already made the important material of nuclear energy industry. Black lead is carbon qualitative element is crystal and mineral, its knot crystal lattice is worn for structure of hexagon layer shape, see a picture 1, 1. The distance between each net layer is 3.

40 people, span of atomic of the carbon in same network layer is 1. 42A. Belonging to 6 brilliant is, provide complete layer shape cleavage. Cleavage face is given priority to with molecular key, weaker to molecular appeal, reason its are natural but buoyancy is very good. Black lead is qualitative soft, black gray; Have fat feeling, can pollute paper. Hardness is 1 ～ 2, increase its hardness to be able to be added to 3 ～ along what perpendicular direction follows foreign matter 5. Specific gravity is 1. 9 ～ 2. 3. Below isolation oxygen condition, its melting point is in 3000 ℃ above, be most be able to bear or endure lukewarm mineral one of. The pure black lead in nature is done not have, often contain the impurity such as Si02, A1203, Fe0, CaO, P2O5, Cu0 among them. These impurity constant with the mineral form such as quartz, pyrite, carbonate appears. In addition, still have the aeriform share such as water, bitumen, CO2, H2, CH4, N2. Because of the analysis of this pair of black lead, except determine outside fixed carbon content, still must determine at the same time volatilize the content of cent and ash content. The craft character of black lead basically decides the crystallization form at it. The black lead with crystallization different pattern is mineral, have different industrial value and use. On industry, differ according to crystallization configuration, natural black lead cent is 3 kinds. 1. Black lead of compact crystallization shape calls black lead of compact crystallization shape lump black lead again. This kind of black lead is crystal and clear crystal is macroscopical. Grain diameter is more than 0. 1 millimeter. Crystal is arranged desultorily, show compact lump construction. This kind: The characteristic of black lead is grade very tall, contain carbolic quantity to be 60 ～ commonly 65 ％ , amount to 80 ～ sometimes 98 ％ , but its plasticity and satiny sex are not as good as scale black lead. 2. Crystal of black lead of scale black lead submits scale form; Deteriorate below the pressure of high strenth and this is become, have the branch of large scale and fine scale. The characteristic of ore of this kind of black lead is grade not tall, be in commonly 3 ％ of 2 ～ , or between 25 ％ of 100 ～ . It is nature in but one of ore with best buoyancy, choose more through be being ground more can get concentrate of high grade black lead. Of this kind of black lead but buoyancy, lubricity, plasticity all compares other type black lead advantageous; Its industrial value is the accordingly greatest. 3. Black lead of character of concealed of concealed crystalloid black lead calls noncrystalline black lead or earthy record black lead again, the crystal diameter of this kind of black lead is less than 1 micron commonly, it is the aggregate of microcrystalline black lead, below the electron microscope only ability sees brilliant body. The characteristic of this kind of black lead is the surface submits earthy form, devoid burnish, lubricity is poor also. Grade is higher. 80 ％ of general 60 ～ . A few is as high as 90 ％ above. Ore is optional the gender is poorer. Black lead because its are special structure, and have following special quality: 1) high temperature resistant model: The melting point of black lead is 3850 ± 50 ℃ , boiling point is 4250 ℃ , although calcination of electric arc of classics superhigh temperature, the loss of weight is very small, hot coefficient of expansion is very small also. Black lead intensity rises along with temperature and strengthen, when 2000 ℃ , black lead intensity raises one times. 2) electric, thermal conductivity: The conductivity of black lead is compared general metalloid mine is 100 times taller. Thermal conductivity exceeds the metallic stuff such as steel, iron, lead. Coefficient of thermal conductivity lifts along with temperature and reduce, fall in extremely high temperature even, black lead becomes adiabatic system. 3) lubricity: The lubricant function of black lead depends on the size of black lead scale, scale is larger, coefficient of friction is smaller, lubricant performance is better. 4) chemical stability: Black lead has good chemical stability below normal temperature, ability acid, alkali resistance and be able to bear or endure of organic dissolvent corrode. 5) plasticity: The tenacity of black lead is good, but the chip with very small the year's harvest. 6) heatproof shake sex: What black lead can withstand temperature when be used below normal temperature is acuteness change and do not send destroy, when temperature is choppy, the bulk change of black lead is not big, won't produce crackle. Natural black lead is mixed with lump black lead scale black lead is best, use is the most extensive. Our country has not discovered field of extensive lump black lead, black lead of scale black lead and concealed crystalloid all has bigger field, formed the base of large-scale exploitation. Natural black lead has a lot of good quality, apply extensively at national economy consequently departmental door, it is especially in industry of metallurgy, mechanical, electric equipment, chemical industry receive wide application. Black lead is had those who highlight is high temperature resistant and be able to bear or endure the property of microtherm, coefficient of expansion is very small, volume is steady, because this can resist the change of urgent cold urgent heat, of black lead high temperature resistant when property and general metal differ to lift when temperature, it is not to tend bate, and its intensity instead heighten. Black lead is the good conductor of heat and report, its conduct heat function and electric function and most metal are about the same, but have its characteristic again, general metal lifts when temperature when, coefficient of thermal conductivity also lifts subsequently, and the coefficient of thermal conductivity of black lead is contrary, when temperature is elevatory, its coefficient of thermal conductivity drops instead. Below extremely high temperature, black lead tends insulation condition, because this is below superhigh temperature condition, the heat proof quality of black lead is very reliable. The plasticity of black lead and lubricity win application on industry already, scale is larger, coefficient of friction is smaller, scale black lead is the accordingly most slippery, lubricity is best, take second place of black lead of compact crystallization shape, lubricity of earthy record black lead is poorer. Black lead is the super material of chemical industry, its chemical stability is very outstanding, it is acid-proof, alkali resistance, anti-corrosive, special place is had in chemical industry. Black lead still is the moderator with admirable atomic reactor, make the utility of black lead entered a new historical level, to make admirable moderator, the extract craft of black lead got further progress, because this black lead already made the important material of nuclear energy industry. CNC Milling CNC Machining