Coating of thermal spraying TBCs organizes the research that the structure affects to high temperature alloy

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[summary] organize change in the light of metallographic of base material of alloy of high temperature of thermal spraying around, and coating of spray heat barrier (English abbreviate: The constituent structure change that base material of the alloy after TBCs) issues in instantaneous high temperature begins research. In making clear process of coating of thermal spraying TBCs as a result, organization of base material of high temperature alloy changes without clear structure; Below 1300K temperature, the organization of high temperature alloy after 10min can form branch brilliant state and separate out 2 Y photograph, and below coequal condition, the organization that uses the base material of high temperature alloy after coating of thermal spraying TBCs is protected did not produce apparent change. 1. Coating of overview heat barrier (abbreviation TBCs) points to normally in high temperature resistant the coat of pottery and porcelain that metallic surface has good and adiabatic effect, it makes base material is avoided suffer high temperature oxidizes and corrode, drop the working temperature of matrix. Empty spaceflight of Ren Hang of technology of heat barrier coating, generate electricity, vessel of metallurgy, ship and car are made wait for a domain to having wide application, inchoate research work is a center with American NASA, study what achievement basically applies at lamina of turbine of air cooling engine to prevent heat and anticorrosion to reach water-cooled or fuel is cooling of type rocket motor outside wall. Technology of 60 time TBCs applies 20 centuries successfully on the lame parts of an apparatus of the nozzle of X-15 rocket and firebox of turbine burning gas. Since 1980, the country such as the United States, Japan, Germany and England invests to begin systematic research to TBCs technology gigantic in succession, sky of Yu Hang of successful application, generate electricity wait for an industry. Current, coating of advanced ceramics heat barrier can make below working environment alloy job temperature reduces 150 ℃ to control. The article passes the constituent structure SEM that issues high temperature alloy to different condition to analyse, coating of differentiate heat barrier plays the protective effect to base material in instantaneous high temperature. 2. Advance copy literary grace uses coating of heat barrier of preparation of system of DH-80 plasma spray, TBCs material chooses Metco204, spray parameter sees a table 1. Base material is chosen cast high temperature alloy. Testing stand of coating high temperature capability is used to have a test to the heat proof quality of heat barrier coating in the experiment. The metallographic organization that through be in to high temperature alloy different position leaves and SEM observation are comparative, judge process of high-energy plasma spray to issue heat barrier coating to organize protective action of the structure to matrix of high temperature alloy to the influence of matrix and instantaneous high temperature. Express 2 it is test program. Among them sample 1 to cast high temperature alloy primitive tissue standard specimen, sample 2 after be coating of MTBCs of μ of plasma spray 200p cast high temperature alloy, sample 3 cast high temperature alloy to do not have what heat barrier coating protects, sample 4 it is those who have coat of 200p μ MTBCs to cast high temperature alloy. 3. Result analysis (the organization that 1) coins the constituent structure of high temperature alloy to cast high temperature alloy is bulkier (show 1 times like the graph) , basically did not wait for axial crystal structure, have Y+y ′ in all crystal appears, at the same time partial carbide distributings to go up in matrix; Distributinging on Y solid solution photograph of aggrandizement of Y ′ dispersion, y ′ Xiang Weiming displays regular diamonds photograph, be in times lower below, can observe apparently the Y+y ′ of chrysanthemum shape in all the carbide photograph of crystal and black, if pursue,2 are shown. (The constituent change after 2) casting alloy overheat pursues 3 it is sample the 3 metallographic after 5min heats below 1300K temperature organize form appearance. It is thus clear that its organization organizes organization of shape of brilliant of translate into branch by loud casting voice, its limb is long, branch brilliant span is bigger, issueing what can see carbide look apparently times higher to distributing and in all the occurrence that brilliant organizes. Graph 4 issue form appearance for SEM, photograph of ′ of Y of visible aggrandizement photograph produced apparent solid dissolve recrystallization, diamonds photograph is organized (if the graph is shown 2 times) as a result of solid dissolve, begin to turn into irregular appearance, call Y ′ 2 times the separate out of the photograph partly from time to tome together, size is the grain of photograph of 2 Y ′ of separate out about 100mm, accompany have look of much petty 2 Y ′ separate out, the specification is in 1300K, heat below the condition of 5min, cast organization of high temperature alloy to produce apparent change, function drops greatly. (Process of 3) thermal spraying pursues to casting the influence of high temperature alloy 5, graph 6 it is the matrix after plasma spray coating respectively constituent metallographic and SEM form appearance. Visible, matrix of high temperature alloy is in plasma spray process organization of its casting appearance did not produce apparent change, remain the axial crystal structure such as loud casting voice, the Y+ Y ′ that there is white on its at the same time in all crystal and carbide photograph. In times taller SEM observation falls, its organization also did not change apparently, remain ′ of aggrandizement photograph Y to distributing to go up in Y solid solution, aggrandizement photograph remains diamonds shape structure. Of the carbide look that also has black at the same time and chrysanthemum shape in all brilliant organization appears. (Coating of the heat barrier below condition of 4) instantaneous high temperature is right the protective action sample that casts high temperature alloy 4 heat below 1300K temperature if the appearance of metallographic organization body after 10min pursues show 7 times. Organization of branch brilliant shape appeared likewise after visible instantaneous high temperature, but its limb is short and thick, branch brilliant span is shorter at the same time, this and sample 3 in occurrence branch brilliant organization has very big distinction, sample distributinging density of 4 branches brilliant is big, this shows TBCs coating has very powerful protection effect to casting matrix of high temperature alloy. Graph 8 it is the form appearance below SEM observation. Visible much calls Y ′ photograph to still be diamonds photograph structure, and only a few photograph of ′ of aggrandizement photograph Y produces solid dissolve. 4. Epilogue (of 1) overheat cast high temperature alloy to form branch brilliant; The appearance of photograph of ′ of Y of its aggrandizement photograph is irregular appearance by lump change, at the same time span of aggrandizement alternate with greatens; Dimension is the grain of photograph of 2 Y ′ of separate out about 100mm. (The course of coating of 2) spray TBCs is right the photograph structure that casts high temperature alloy does not have apparent effect. (After the overheat of high temperature casting alloy of coating of 3) spray TBCs, also branch brilliant appears, but the separate out that does not have Y ′ photograph 2 times, this makes clear coating of thermal spraying TBCs to be able to put the function below instantaneous high temperature to stabilize play to protect action to cast high temperature alloy. CNC Milling