The high temperature resistant melt erosive of a kind of guard electrode matrix ceramic coating and preparation method thereof
Technical field
Preparation one deck ceramic coating on the metallic surface that the energy that the present invention relates to utilize high energy plasma arc or flame to produce uses in high-temperature fusant, particularly a kind of guard electrode matrix is high temperature resistant, anti-, and melt corrodes and the composite ceramic coat and the preparation method of high temperature thermal shock.
Background technology
Desire improves the service life of the metal that uses in the high-temperature fusant, adopts the effect of surface ceramic coat resist technology very remarkable.Under the condition of routine, general pottery all belongs to inert material, with high-temperature fusant chemical reaction does not take place, and oxide compound is the ceramic coating material of using always.
The high-temperature smelting pot electrode generally adopts the high-melting-point refractory material to make, and adopts Graphite Electrodes as steel-making with the high-temperature electric arc stove.Silicate institute of the Chinese Academy of Sciences and Xiangfan viscose glue technical institute all take high-temperature oxidation resistant coating protection steel-making with electric arc hearthstone electrode ink, can improve electrode life and reduce power consumption.Report in this steel technology 1996, (3) adopts oxidation resistant coating to reduce consumption of electrode.This type of oxidation resistant coating is the brushing of inorganic paint and makes, and the coating cohesive strength is not high, and washing away of anti-melt not.Glass Int.Mar.1984; the report related content of plasma spraying FeCrAl coating protection molybdenum electrode among p42~42 Protectionof molybdenum electrodes in forehearths during commissioning by the use ofFeCrAl coating; but the FeCrAl metal is soluble in the melt of melting, changes certain specific character of melt material as impurity.The electrode surface of making at electric arc furnace molybdenum alloy or other superalloy adopts the method for inert ceramic material coating shielding protection not appear in the newspapers.
Summary of the invention
The objective of the invention is to overcome the deficiency of the high temperature resistant melt etching resist of above-mentioned guard electrode matrix, the high temperature resistant melt erosive of a kind of guard electrode matrix inert ceramic material coating and preparation method thereof is provided.
For reaching goal of the invention, the high temperature resistant melt erosive of a kind of guard electrode matrix coating that the present invention proposes is bottom with the molybdenum disilicide, be surface layer with the reunion ball-type powder spraying ceramic coating of zirconium silicate or high purity zircon micropowder system.
Described thickness of ceramic coating is 0.4~0.7mm, is generally 0.4~0.5mm.
The high temperature resistant melt erosive of a kind of guard electrode matrix of the present invention coating; its described coating comprises that thickness is less than 0.1mm molybdenum disilicide bottom; with the compound powder bed of pressing a, b, c, the spraying of d component sequential scheduling thickness, compound powder by the proportioning of 1000 grams is:
A) zirconium silicate or zircon ZrO
2SiO
2350~390 grams, molybdenum disilicide MoSi
2590~630 grams, two kinds of material sum 〉=980 grams, binding agent is supplied surplus;
B) zirconium silicate or zircon ZrO
2SiO
2550~590 grams, molybdenum disilicide MoSi
2390~430 grams, two kinds of material sum 〉=980 grams, binding agent is supplied surplus;
C) zirconium silicate or zircon ZrO
2SiO
2750~790 grams, molybdenum disilicide MoSi
2190~230 grams, two kinds of material sum 〉=980 grams, binding agent is supplied surplus;
D) zirconium silicate or zircon ZrO
2SiO
2〉=980 grams, binding agent is supplied surplus;
Wherein said zircon is the high-purity zirconium diamond stone, and zirconium silicate and high-purity zirconium diamond stone are reunion ball-type powder.Described total coating thickness is 0.4~0.7mm, is generally 0.4~0.5mm.
Described zirconium silicate or high-purity zirconium diamond stone powder and molybdenum silicide powder granularity are 0.5~15 μ m.
Described electrode matrix is the electrode bar that molybdenum alloy that electric smelter is used is made.
The coating method of the high temperature resistant melt erosive of described guard electrode matrix coating may further comprise the steps:
1) the molybdenum alloy electrode bar periphery to required spraying carries out sandblasting;
2) spray one deck molybdenum disilicide bottom with the plasma powder spraying method at molybdenum alloy electrode bar periphery, spray described zirconium silicate or zircon reunion ball-type powder again, sprayed coating thickness 0.4~0.7mm through sandblasting.
The coating method of the high temperature resistant melt erosive of described guard electrode matrix coating may further comprise the steps:
1) the molybdenum alloy electrode bar periphery to required spraying carries out sandblasting;
2) spray one deck molybdenum disilicide bottom with the plasma powder spraying method at molybdenum alloy electrode bar periphery through sandblasting, thickness is less than 0.1mm, then described spray material is sprayed on the electrode bar periphery total thickness 0.4~0.7mm by described a, b, c, d component sequential scheduling thickness.
Its binding agent is general mineral binder bond and organic binder bond.
Zirconium silicate of the present invention or zircon also can be used alone as the little molybdenum alloy surface high temperature resistance melt erosive supercoat of thermal expansivity, or use molybdenum disilicide MoSi under the little working condition of thermal shocking
2Form the tie coat of two-layer or three-decker as bottom, be used for the electrode work condition environment not too under the harsh conditions.
Zirconium silicate of the present invention or zircon (ZrO
2SiO
2) and molybdenum disilicide (MoSi
2) Conglobation type ceramic powder unitized design, and the compound coating that adopts plasma spraying or other spraying technologies to prepare, have following excellent
1, zirconium silicate or zircon (ZrO
2SiO
2) material surface and alkaline melt be nonwetting, has excellent erosion-resisting characteristics; Molybdenum disilicide (MoSi
2) material and molybdenum matrix bond better performances, and in≤1400 ℃ alkaline melten glass electric arc smelting furnace, molybdenum disilicide (MoSi
2) can form the vitreous state tissue, play self-enclosed effect, thereby stop up the space that exists in the coating, played the effect that stops melt endosmosis protection molybdenum matrix.
2, zirconium silicate or zircon (ZrO
2SiO
2) and molybdenum disilicide (MoSi
2) material is close with the thermal expansivity of molybdenum and some superalloys, phase constitution is stable under≤1400 ℃ of high temperature, and in actual use, transformation stress and thermal stresses between coating and body material are less, can not cause the coating shedding phenomenon.
3, zirconium silicate or zircon (ZrO
2SiO
2) and molybdenum disilicide (MoSi
2) design of composite ceramic coat, and adopt plasma spraying and the preparation of other spraying technologies, coating and molybdenum alloy or other superalloy bar substrate combinating strength height.
Embodiment
Embodiment 1
1, the zirconium silicate fines of≤10 μ m granularities is made the spherical dusty spray of reuniting, the content 〉=98wt% of fines wherein, binding agent is supplied surplus.
2, surface finish alligatoring, activation treatment are carried out in the molybdenum alloy bar material cylindrical surface of required spraying;
3, with plasma powder spraying and gas explosion spraying method at molybdenum alloy and the high-temperature alloy surface spraying Zirconium silicate ceramic coating handled, thickness 0.5mm;
4, after coating preparation finishes, if adopt the method for dip-coating or brushing, the phosphoric acid salt or the potash water glass that are coated with about last layer 0.1mm at the ceramic coating outside surface carry out the sealing of hole processing again, and the coating result of use can be better.
Embodiment 2
1, the zircon of≤10 μ m granularities and molybdenum disilicide fines are made the spherical dusty spray of reuniting respectively, the content 〉=98wt% of fines wherein, binding agent is supplied surplus.
2, molybdenum alloy or other superalloy electrode bar periphery to required spraying carries out sandblasting;
3, spray one deck molybdenum disilicide bottom, thickness 0.1~0.15mm with plasma powder spraying or other heat spraying methods at molybdenum alloy or other superalloy electrode bar periphery through sandblasting;
4, adopt powder plasma spraying and gas explosion spraying method to spray the zircon ceramics coating on the molybdenum disilicide bottom, total thickness is less than 0.7mm.
5, after coating preparation finishes, if adopt the method for dip-coating or brushing, the phosphoric acid salt or the potash water glass that are coated with about last layer 0.1mm at the ceramic coating outside surface carry out the sealing of hole processing again, and the coating result of use can be better.
Embodiment 3
1, with the zirconium silicate and the molybdenum disilicide fines of≤10 μ m granularities, be mixed with the spherical dusty spray of reunion of four kinds of heterogeneities according to following ratio, be example with 1000 grams
Zirconium silicate (ZrO
2.SiO
2) molybdenum disilicide (MoSi
2)
A) 350~390 grams, 590~630 grams, two kinds of material sum 〉=980 grams
B) 550~590 grams, 390~430 grams, two kinds of material sum 〉=980 grams
C) 750~790 grams, 190~230 grams, two kinds of material sum 〉=980 grams
D) 〉=980 restrain
Binding agent is supplied surplus.
2, molybdenum alloy or other superalloy electrode bar periphery to required spraying carries out sandblasting;
3, spray one deck molybdenum disilicide bottom with plasma powder spraying or other heat spraying methods at molybdenum alloy or other superalloy electrode bar periphery through sandblasting, thickness is less than 0.1mm;
4, the spherical dusty spray of the reunion of above-mentioned preparation is sprayed with powder plasma, by a), b), c), d) component sequential scheduling thickness is sprayed on the molybdenum alloy electrode bar periphery, total thickness is less than 0.7mm.
5, after coating preparation finishes, if adopt the method for dip-coating or brushing, the phosphoric acid salt or the potash water glass that are coated with about last layer 0.1mm at the ceramic coating outside surface carry out the sealing of hole processing again, and the coating result of use can be better.