The coating that can protect metal strengthening to conduct heat in the metal objects heating process
Technical field
The present invention relates to metallic paint; relate to a kind of metalliferous material or workpiece heating process of being used for; for example behind the metal strand before the hot-work, behind the metal strand cutting section to the coating of going into the stokehold, relate in particular to a kind of coating that in metalliferous material or workpiece heating process, is used to protect metal, enhancement of heat transfer.
Background technology
Metalliferous material or workpiece such as steel ingot, steel billet, steel plate and other metal need workpiece is put into the industrial furnace internal heating in hot procedure.What adopt at present is that this kind type of heating exists following two shortcomings with the exposed mode of putting into the industrial furnace internal heating of workpiece:
1, metalliferous material in heating process with furnace gas generation mass transfer.
(1) oxygen generation chemical reaction in metal and the stove, namely metal sucks oxygen element from furnace gas, generates oxide in the metal surface, is commonly called as " scaling loss ", reduces recovery rate of iron.
(2) intrametallic trace element is taken away by furnace gas, forms trace element loss layer in the metal surface.Silicon-manganese spring steel for example, this kind material hardening capacity is good, is used for making heavily stressed spring, is widely used in industries such as automobile making.But silicon-manganese spring steel surface in heating process produces oxidation and decarbonization easily, forms decarburized layer, reduces elasticity and the fatigue strength of spring.This just causes subsequent handling to strip off the skin to metal works processing or Carburization Treatment, increase thus operation, reduce productivity ratio and recovery rate of iron.
2, the heat time heating time of metalliferous material relatively longer, the speed of namely accepting heat in stove is low.
In the industrial furnace more than 500 ℃, conduct heat take radiant heat transfer as main.The heat transfer of flame space is a very complicated complex heat transfer process in the industrial furnace, and the stove kind is more, and complex heat transfer is different in the different stoves, its situation complexity.In a stove that is full of flame or high-temperature furnace gas, exist three different temperature provinces: furnace gas (or flame), furnace lining (furnace wall and furnace roof), material.Because flame temperature is very high, so main heat transfer type is radiation in the stove, and conduction and convection current only account for littler proportion in heat flow.In addition, furnace wall also can dissipated heat for peripheral air, and this thermosteresis also has some influences to temperature in the stove.Blackness ε
mRepresent the radiative transfer performance of material, ε
mBe worth greatly more, the radiative transfer performance is good more.Because the metalliferous material blackness is lower, such as the surperficial blackness ε of steel billet
m≤ 0.8, the smooth metal surface of the work blackness after the processing is far below this numerical value.And the blackness value of some material is: 1>ε
m>0.9.Therefore, Luo Lu metalliferous material is longer relatively heat-up time.
In the conventional use of metalliferous material, coating or paints and lacquers protection are used very extensive.Such as household appliances, automobile, engineering machinery, steel construction, roof panel etc., all adopt coating or paint that metal is protected, have simultaneously effect attractive in appearance.
The application of high-temperature coatings on the high temperature Thermal Equipment is also quite extensive.Abroad, the ET-4 coating that Britain CRC company produces, CRC-10A produced in USA, G-125, SBE coating, CRC1100, CRC1500 coating that Japan produces, coating blackness (emittance) ε
mReach 0.9, the High-temp. kiln inwall that is used for industries such as metallurgy, machinery, petrochemical industry, electric power applies, and reaches the effect that protection stove inwall promptly prolongs the stove inwall life-span, improves radiative transfer intensity.
In China, developed multiple high temperature radiating coating material, for example: ambient cure phosphoric acid salt high-temperature resistant coating, high temperature organosilicon paint, contain the carborundum coating that chromium high temperature organosilicon paint, zircon/zirconium white compound are done high-temperature resistant coating and high temperature resistant seal agent, acid-resistant and anti-high-temperature coating for boiler dust remover, carbon containing refractory antioxidant coating, the paint adhesion agent of stove liner high temp, infrared radiation and improved fan efficiency, or the like.These coating majorities are used for the High-temp. kiln inwall and apply, and reach the effect that protection stove inwall promptly prolongs the stove inwall life-span, improves radiative transfer intensity.Minority is for the protection of the metal in using, and prolongs metal service life.
But the high-temperature coatings product of above-mentioned domestic and international application; the High-temp. kiln inwall that only is used for industries such as metallurgy, machinery, petrochemical industry, electric power applies; minority is used for protecting the metal of use; also be not used for metalliferous material or workpiece heating process, for example behind the metal strand before the hot-work, behind the metal strand cutting section to the operation of going into the stokehold.
Summary of the invention
Task of the present invention provides the coating that can protect the metal enhancement of heat transfer in a kind of metal objects heating process, and it has solved existing high-temperature coatings product and has failed to be used for metalliferous material or the workpiece heating process problem with protection metal, enhancement of heat transfer.
Technical solution of the present invention is as follows:
The coating that can protect metal strengthening to conduct heat in a kind of metal objects heating process, the components by weight percent of described functional paint is: 100~400 parts of SiC, 0~400 part of chromite ore; 100~200 parts of clay powders, 0~100 part of carbon black, 5~20 parts of titanium dioxides; 5~20 parts of lithopones, 5~20 parts of zinc powders, Al
2O
30~100 part, 200~600 parts in PA80 glue is the following solids fraction particle of 320 orders, and water is surplus.
During use, functional paint of the present invention is coated in workpiece surface to be heated, puts into the burner hearth heating then, heat after promptly " putting on clothes ", played the effect of protecting metal, enhancement of heat transfer to workpiece.Functional paint of the present invention is specially adapted to the heating process in the metal strand post-treatment process, promptly behind the metal strand before the hot-work, behind the metal strand cutting section to the operation of going into the stokehold.
The functional paint that applies has the dual-use function of protection metal, augmentation of heat transfer, it also can be a kind of single functional paint, only form fine and close protective layer at surface of the work, intercept mass transfer between workpiece and the burner hearth gas, can prevent workpiece oxidation and decarburization such as graphite, SiC matter coating, perhaps only form high radiation coating at surface of the work, to improve firing rate, for example a kind of Gr2O3 matter coating; It also can be composite functional coating, have aforementioned two kinds of functions concurrently, for example adopt a kind of micro-nano high-temp. far infrared energy-saving coatings, the granular superfine of this coating, reach nano-scale particle, form fine and close ultra-thin overcoat, strong adhesion, difficult drop-off at workpiece substrate, effectively intercept workpiece and furnace gas generation mass transfer, reduce oxidation and trace element and take off mistake, this coating blackness is big, blackness ε
m=0.93, coating can be accepted heat quickly in stove, then in the conduction heat transfer mode to inside workpiece heat conduction, strengthened the workpiece heat transfer.
The coating method of functional paint of the present invention can adopt the modes such as brushing, immersion, roller coat or spraying.
Functional paint of the present invention is used extremely extensive in metalliferous material or workpiece heating process, adopts the exposed mode of putting into the industrial furnace internal heating of workpiece, is being heated metal works surface-coated functional paint post-heating, and its advantage is as follows:
1, reduces the burning burn out rate.
2, trace element takes off the mistake rate in the reduction metal, can remove some steel grade to strip off the skin operation or add micro-operation.
3, improve firing rate, improve existing firing equipment output and productivity ratio.
4, in pusher-type furnace, steel bonding takes place in heated steel billet sometimes, can prevent steel bonding after applying this functional paint.
Functional paint of the present invention has broad application prospects.China has become the annual output steel and has surpassed 400,000,000 tons country, and wherein the part steel are through repeatedly exposed heating.Take the steel hot rolling operation as example, China in this operation heating process average burning burn out rate greater than 1%, using functional paint of the present invention can drop to this operation burn out rate below 0.3%, only above first advantage annual just can for China overcharge steel above 2,800,000 tons.Functional paint of the present invention then has bigger application potential as other heating process that is used for the iron and steel material and the heating process of other metal.
Embodiment
The present invention is the coating that can protect metal strengthening to conduct heat in a kind of metal objects heating process; the components by weight percent of this functional paint prescription is: 100~400 parts of SiC; 0~400 part of chromite ore; 100~200 parts of clay powders; 0~100 part of carbon black, 5~20 parts of titanium dioxides, 5~20 parts of lithopones; 5~20 parts of zinc powders, Al
2O
30~100 part, 200~600 parts of PA80 glue or waterglass, these components are the following solids fraction particle of 320 orders, and water is surplus.
The preparation method of this functional paint is, the above-mentioned components by weight percent of functional paint is mixed, and makes thick fluid, applies to be fit to corresponding spraying, roller coat or brushing machinery.
The application method of this functional paint is, functional paint is applied to heating process in the metal strand post-treatment process, be to the operation of going into the stokehold behind the metal strand before the hot-work, behind the metal strand cutting section, increased the step of giving material or workpiece coating coating, heated to after being heated metal objects surface-coated functional paint.The application of this functional paint on production-line technique, has been improved recovery rate of iron, reduced that trace element takes off mistake in the metal.
This functional paint can be a kind of single functional paint, forms coat, only plays barrier metal workpiece and furnace gas effect of mass transmitting; Also can be another kind of single functional paint, form coat, only play reinforced metal workpiece and furnace gas, furnace wall heat transfer effect.That is to say, use single functional paint, form coat, played single kind and protected or strengthen function, for example heated steel billet can prevent steel bonding in the pusher-type furnace after applying this functional paint.
This functional paint can be a kind of dual-function paint, forms coat, has both played barrier metal workpiece and furnace gas effect of mass transmitting, plays again reinforced metal workpiece and furnace gas, furnace wall heat transfer effect.
This functional paint is easy to that its removal is had easy removal capacity after finishing protection metal function before rolling processing, augmentation of heat transfer function.
According to the above-mentioned prescription of functional paint of the present invention, can be realized by the specific embodiment of following prescription.
Embodiment 1:
The components by weight percent of this functional paint is: 400 parts of SiC, 0 part of chromite ore, 200 parts of clay powders, 100 parts of carbon blacks, 20 parts of titanium dioxides, 20 parts of lithopones, 20 parts of zinc powders, Al
2O
3100 parts, 600 parts in PA80 glue, water are surplus.
Embodiment 2:
The components by weight percent of this functional paint is: 100 parts of SiC, 400 parts of chromite ore, 100 parts of clay powders, 0 part of carbon black, 5 parts of titanium dioxides, 5 parts of lithopones, 5 parts of zinc powders, Al
2O
30 part, 600 parts in PA80 glue, water are surplus.
Embodiment 3:
The components by weight percent of this functional paint is: 250 parts of SiC, 300 parts of chromite ore, 150 parts of clay powders, 50 parts of carbon blacks, 15 parts of titanium dioxides, 15 parts of lithopones, 10 parts of zinc powders, Al
2O
350 parts, 600 parts in PA80 glue, water are surplus.
Embodiment 4:
The components by weight percent of this functional paint is: 200 parts of SiC, 200 parts of chromite ore, 180 parts of clay powders, 80 parts of carbon blacks, 12 parts of titanium dioxides, 18 parts of lithopones, 6 parts of zinc powders, Al
2O
320 parts, 500 parts in PA80 glue, water are surplus.
Embodiment 5:
The components by weight percent of functional paint is: 150 parts of SiC, 100 parts of chromite ore, 110 parts of clay powders, 10 parts of carbon blacks, 8 parts of titanium dioxides, 9 parts of lithopones, 7 parts of zinc powders, Al
2O
370 parts, 200 parts in PA80 glue, water are surplus.
Certainly, those skilled in the art in the present technique field will be appreciated that, the foregoing description only is to be used for illustrating the present invention, and be not as limitation of the invention, as long as in connotation scope of the present invention, all will drop in the scope of claim of the present invention variation, the modification of the foregoing description.