CN101514474B - Method for preparing Y2SiO5/MoSi2 composite coat by sonoelectrodeposition - Google Patents

Abstract

The invention relates to a method for preparing a Y2SiO5/MoSi2 composite coat by sonoelectrodeposition. Y2SiO5/MoSi2 powder is used as raw material to be respectively made into Y2SiO5/MoSi2 coats with compact structure, microcrack and different thickness in certain powder material proportion and under certain temperature and voltage and different ultrasonic powers. The method has the advantages of simple technical control and uniform coat, ensuring that the coat has better connecting property and can be used for product with complex surface, and the method can obtain an external antioxidant coat with controllable structure and good performance under low temperature. Under comparatively low temperature, the method can prepare the Y2SiO5/MoSi2 composite coat with good connection property with a substrate, high antioxidant property and controllable coat thickness. The prepared coat can protect carbon/carbon composite material under high temperature effectively, and the oxidative weight loss of a sample is less than 0.5 percent after being oxygenated for 200 hours under the high temperature of 1600 DEG C.

Description

A kind of acoustic-electric deposition preparation Y 2SiO 5/ MoSi 2The method of compound coating

Technical field

The present invention relates to a kind of Y ₂SiO ₅/ MoSi ₂The preparation method of compound coating is specifically related to a kind of acoustic-electric deposition preparation Y ₂SiO ₅/ MoSi ₂The method of compound coating.

Background technology

Carbon/carbon compound material becomes the focus of people's research gradually in recent years.Because the carbon/carbon compound material thermal expansivity is low, density is low, anti-ablation, corrosion-resistant, stable friction factor, the heat-conductivity conducting performance is good and characteristics such as high strength, high-modulus, the characteristic that goes up not down with temperature rising mechanical property particularly, so it is applied to Aeronautics and Astronautics and civilian industry field.Yet, its many above-mentioned character is only under inert atmosphere or be lower than under 450 ℃ the condition and could keep, oxidation weight loss will make the mechanical property of carbon/carbon compound material obviously descend, thereby limit it as the widespread use of high-temperature refractory under oxidizing atmosphere.Therefore, solving carbon/carbon compound material high temperature oxidation protection question is the prerequisite that makes full use of its performance.

Oxidation resistant coating is considered to solve the effective ways of carbon/carbon compound material high temperature oxidation protection question, but because the special physicochemical characteristic of carbon/carbon compound material, many high temperature ceramic material can't directly use as high temperature coating, therefore adopt the compound coating method of transition layer/external coating (EC) (high temperature ceramic material) mostly, in transition layer, because SiC and carbon/carbon compound material have good physical chemistry consistency, so generally adopted.MoSi ₂(coefficient of expansion is 8.3 * 10 at 300-1340K ^-6/ K) under 1800 ℃ of anti-oxidant atmosphere, have high-temperature stability and have self-healing function, so have good antioxidant effect, be widely used in the inoxidzable coating of superalloy, refractory metal.But since its coefficient of expansion and C/C (coefficient of expansion is about 1.2 * 10 ^-6/ K) differing greatly, use can cause the cracking of coating and peel off separately, thereby makes the coating failure.So select for use have high-melting-point, the yttrium silicate material and the MoSi of excellent physical and chemical performances such as low Young's modulus, low thermal coefficient of expansion, low vaporization at high temperature rate, low high-temperature oxygen rate of permeation and resistance to chemical attack ₂Constitute the compound anti-oxidation external coating (EC), and to adopt SiC be that transition layer has improved external coating (EC) and the unmatched problem of the C/C matrix material coefficient of expansion largely, prolonged C/C matrix material work-ing life at high temperature, played better oxidation-protective effect.

Up to the present, the technology of preparing of oxidation resistant coating mainly contains hot isostatic pressing method, molten slurry coating sintering method, plasma spraying method and original position forming method etc.But because above method all needs at high temperature just can prepare more satisfactory coating.And higher preparation temperature may cause certain damage to matrix, makes coating have certain defective in varying degrees, so low temperature preparation technology's exploitation is one of direction of endeavouring of investigator always.

The characteristics of acoustic-electric sedimentation at first are the combinations of sonochemistry technology and electro-deposition techniques, and the reacting activation energy that utilizes localized hyperthermia that ultrasonic wave produces in reaction system and high pressure effectively to reduce suspended particles, make it in electrodeposition process, react more complete and abundant.In addition, utilize the concussion effect of ultrasonic wave in suspension, not only can overcome electrodeposition process in technologic defective, and can remedy the bonding force problem that common electrical deposits indeterminable inside and outside coating.Phase transformation and the embrittlement adopting this method can avoid adopting conventional high-temperature to apply and cause solve in the coating preparation process thermal damage to matrix to a certain extent; Secondly, deposition process is non-streamlined process, can form uniform settled layer at the matrix surface of complex-shaped or porous surface, and the accurate control coating composition of energy, thickness and porosity, make heterogeneous compound coating of simple efficient production and graded ceramics coating become possibility; Moreover whole process is that the orientation of charged particle moves, a large amount of gases affect coatings that produce in the time of can be because of the brine electrolysis solvent and the bonding force of matrix.

Adopting electrodip process to prepare in the research of iridium silicate coating layer, Chr.Argirusis, T.Damjanovic, M.Stojanovic, G.Borchardt (Chr.Argirusis, T.Damjanovic, M.Stojanovic, G.Borchardt.Current Research inAdvanced Materials and Processes, 2005, pp.451-456) wait human 70wt%Y ₂Si ₂O ₇And 30wt%Y ₂SiO ₅After nano-powder fully disperseed in b propanol, the deposition voltage deposit of 60V 1-3 minute, preparing thickness on the C/C-Si-SiC matrix material was the compound external coating (EC) of yttrium silicate of 15-30 μ m.This coating plays C/C in 1500 ℃ still air and reaches 100 hours protection.Huang Jianfeng (Huang Jian-Feng, Zeng Xie-Rong, Li He-Jun, Ceramics International, 2006 (32): 417-421.Huang Jian-Feng, ZengXie-Rong, Li He-Jun, Journal of Material Science, 2004 (39): 7383-7385) waiting the yttrium silicate nano powder with gradient composition is spraying raw material, adopts the Y of plasma spraying method in SiC undercoat surface preparation ₂O ₃2SiO ₂/ Y ₂O ₃1.5SiO ₂/ Y ₂O ₃SiO ₂Gradient composite coating has been brought into play different components yttrium silicate properties of materials preferably, and material weightlessness is lower than 2% behind 1600 ℃ of following oxidation 116h; Y in this coating system ₂O ₃And SiO ₂Distribution gradient has greatly been alleviated the thermal stresses of coating inside, outer field Y ₂O ₃SiO ₂(Y ₂SiO ₅) then play the effect of thermal barrier coating, reduced internally coated service temperature, help improving anti-oxidation of coating.In addition, for MoSi ₂The preparation of oxidation resistant coating, once (once mediate banyan, Yang Zheng such as mediate banyan, Li Hejun, aviation journal, 1997,18 (4): the once mediate banyan of 427-431., Li Hejun, Yang Zheng, silicate journal, 1999,27 (1): the once mediate banyan of 8-15., Li Hejun, the matrix material journal, 2000,17 (2): the 42-45.) Si-MoSi for preparing with entrapping method ₂Coating comprises MoSi ₂/ SiC two-phase layer, SiC tight zone and Si spreading area three parts, oxidation resistant coating is 1500 ℃ of oxidations through 242h, and the rate of weight loss of sample is 0.57%, and the oxidation weight loss rate stabilization is 2.34 * 10 for a long time ^-5G/m ².s; 1600 ℃ of oxidation 115.5h rate of weight loss are 2.65%.

Summary of the invention

The objective of the invention is to overcome the shortcoming of above-mentioned prior art, provide that a kind of technology controlling and process is simple, preparation temperature is low, coating structure and the controlled acoustic-electric deposition preparation Y of pattern ₂SiO ₅/ MoSi ₂The method of compound coating, controlled by coating structure and pattern that the present invention prepares, compact structure, have better bonding force and antioxidant property.

For achieving the above object, the technical solution used in the present invention is:

1) at first, selects the analytically pure yttrium silicate (Y of 0.05-5 micron for use ₂SiO ₅), pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=2.5-5g: 150ml is mixed with suspension, after 1000-2000r/min stirs 8-12h, ratio in 0.5-1.5g/L is introduced iodine in suspension, after continuing mechanical stirring 8-12h, place ultrasonic wave standby behind vibration 10-60min under the power of 100-500W;

2) secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 50-100 micron thickness SiC coating in advance;

3) then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 50-100 ℃, the control ultrasonic power is 80-150W, the control deposition voltage is 50-300V, and depositing time is 10-60min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode;

4) carbon/carbon compound material is placed in 60-100 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.

The present invention adopts the acoustic-electric sedimentation at carbon/carbon fiber reinforced silicon carbide matrix composite surface preparation Y ₂SiO ₅/ MoSi ₂The compound anti-oxidation external coating (EC) utilizes Y ₂SiO ₅, MoSi ₂Powder is a raw material, and according to certain powder proportioning, under certain temperature and voltage, different ultrasonic powers can be prepared Y compact structure, that have micro-flaw, different thickness respectively ₂SiO ₅/ MoSi ₂Coating.The advantage of this method is that technology controlling and process is simple, and coating is even, makes coating have better bonding force, can be used for surperficial complex product, and can obtain controllable structure and well behaved anti-oxidant external coating (EC) at low temperatures.Under relatively low temperature, can prepare and matrix bond is good, antioxidant property is high, coat-thickness is controlled Y ₂SiO ₅/ MoSi ₂Compound coating.Coatings prepared can at high temperature effectively be protected carbon/carbon compound material, at the oxidation weight loss of oxidation sample after 200 hours under 1600 ℃ the high temperature less than 0.5%.

Embodiment

Embodiment 1: at first, select 5 microns analytically pure yttrium silicate (Y for use ₂SiO ₅), pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=2.5g: 150ml is mixed with suspension, after 1000r/min stirs 8h, ratio in 0.5g/L is introduced iodine in suspension, after continuing mechanical stirring 8h, place ultrasonic wave standby behind vibration 20min under the power of 100W; Secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 50 micron thickness SiC coatings in advance; Then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 50 ℃, the control ultrasonic power is 80W, the control deposition voltage is 75V, and depositing time is 15min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode; Carbon/carbon compound material is placed in 60 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.

Embodiment 2: at first, select 1 micron analytically pure yttrium silicate (Y for use ₂SiO ₅), pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=3g: 150ml is mixed with suspension, after 1500r/min stirs 10h, ratio in 1.5g/L is introduced iodine in suspension, after continuing mechanical stirring 10h, place ultrasonic wave standby behind vibration 40min under the power of 200W; Secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 80 micron thickness SiC coatings in advance; Then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 80 ℃, the control ultrasonic power is 100W, the control deposition voltage is 200V, and depositing time is 30min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode; Carbon/carbon compound material is placed in 80 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.

Embodiment 3: at first, select 0.05 micron analytically pure yttrium silicate (Y for use ₂SiO ₅), pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=5g: 150ml is mixed with suspension, after 2000r/min stirs 12h, ratio in 1g/L is introduced iodine in suspension, after continuing mechanical stirring 12h, place ultrasonic wave standby behind vibration 60min under the power of 300W; Secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 100 micron thickness SiC coatings in advance; Then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 100 ℃, the control ultrasonic power is 150W, the control deposition voltage is 300V, and depositing time is 60min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode; Carbon/carbon compound material is placed in 100 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.

Embodiment 4: at first, select 0.5 micron analytically pure yttrium silicate (Y for use ₂SiO ₅), pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=4g: 150ml is mixed with suspension, after 1800r/min stirs 11h, ratio in 1.3g/L is introduced iodine in suspension, after continuing mechanical stirring 9h, place ultrasonic wave standby behind vibration 10min under the power of 500W; Secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 90 micron thickness SiC coatings in advance; Then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 70 ℃, the control ultrasonic power is 130W, the control deposition voltage is 50V, and depositing time is 10min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode; Carbon/carbon compound material is placed in 90 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.

Claims (1)

1. an acoustic-electric deposition prepares Y ₂SiO ₅/ MoSi ₂The method of compound coating is characterized in that:

1) at first, selects the analytically pure yttrium silicate Y of 0.05-5 micron for use ₂SiO ₅, pure MoSi ₂Powder, analytically pure Virahol and iodine are starting material, with Y ₂SiO ₅And MoSi ₂By 1: 1 mass ratio mix mixture, ratio in mixture: Virahol=2.5-5g: 150ml is mixed with suspension, after 1000-2000r/min stirs 8-12h, ratio in 0.5-1.5g/L is introduced iodine in suspension, after continuing mechanical stirring 8-12h, place ultrasonic wave standby behind vibration 10-60min under the power of 100-500W;

2) secondly, above-mentioned suspension is added in the electrodeposit reaction device, be anode with the Graphite Electrodes, be negative electrode with the carbon/carbon compound material that deposited 50-100 micron thickness SiC coating in advance;

3) then, reactor is put into ultrasonic generator, simultaneously with constant temperature water bath to 50-100 ℃, the control ultrasonic power is 80-150W, the control deposition voltage is 50-300V, and depositing time is 10-60min, closes the deposition power supply after galvanic deposit is finished, stop heating simultaneously, treat that the electrodeposit reaction device is cooled to the carbon/carbon compound material that takes out after the room temperature as negative electrode;

4) carbon/carbon compound material is placed in 60-100 ℃ the loft drier drying with distilled water wash and promptly finishes Y ₂SiO ₅/ MoSi ₂Compound coating be prepared into Y ₂SiO ₅/ MoSi ₂The carbon/carbon compound material that compound coating applies.