最新刊期
卷 38 ， 期 7 ， 2018
- 摘要：Using copper-mould spray casting and isothermal heat treatment,sub-rapid solidification and precipitation behavior of AZ91 alloy with 2% nano SiC were investigated to reveal the influences of SiC particle on grain refinement and precipitation.The experimental results show that both the quenching by copper mould and the addition of SiC can promote refinement and reduce solute segregation,which suppress the formation of divorce eutecticβphase in grain boundary.After aging treatment at 200 ℃for 2 h,the SiC particles can increase the dislocation density and lattice distortion energy.Consequently,granular discontinuous precipitates can be formed along the grain boundary,and the solute content of supersaturated solid solution is decreased.With increasing aging time to 16 h,sufficient atomic diffusion can take the coexistence of discontinuous precipitation and continuous precipitation modes,which forms aperpendicular distribution of strip precipitates to the grain boundary and non directional precipitates with granular or short rod inside grain.Moreover,the hardness of primary grain can be increased significantly.关键词：Magnesium Alloys;Non-equilibrium Solidification;Aging Treatment;Grain Refinement;Precipitation
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发布时间：2023-12-18 - 摘要：Effects of solid solution treatment at different temperature on biological corrosion resistance of ZK60 magnesium alloy were investigated.The corrosion behavior of the alloy in the simulated body fluid（SBF）solution was evaluated by immersion test and electrochemical test.The microstructure and morphology of corrosion product were observed by OM（optical microscopy）and SEM（scanning electronic microscopy）.The compositions of corrosion product were analyzed by EDS.The results reveal that the second phase in the as-cast alloy is gradually dissolved after the solid solution treatment,and the potential difference between the matrix and the second phase is decreased,which reduces the tendency of the alloy galvanic corrosion and localized corrosion and improves the corrosion resistance of the alloy.The ZK60 alloy presents desirable biological corrosion resistance at solution temperature of 330℃,where its corrosion rate reaches 2.573 mm/a,and its corrosion current and corrosion potential are 0.205 mA/cm2 and-1.504 V,respectively.关键词：ZK60 Magnesium Alloy;Solution Temperature;SBF Solution;Biological Corrosion Resistance
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发布时间：2023-12-18 - 摘要：The TiC particulate-reinforced titanium matrix composites（TMCs）were fabricated by in situ synthesis using pure titanium and graphite powder.The calculated volume fraction of reinforced phase TiC was 2%,4%,6%,8%,10%,respectively.The effect of the TiC volume fraction on the microstructure and friction properties of titanium matrix composites were investigated.The results show that with TiC content increase,the morphology of TiC in the matrix alloy is transformed from fibous,short rod structre into dendritic structure,and hardness is increased from 30.8 HRC to 46.2 HRC.When the volume fraction of TiC is 6%,the hardness reaches the maximum and the average friction coefficient of wearing against Cr12MoV steel is decreases from 0.46 to 0.37 at 100 Nand 100 r/min.The main mechanism of dry sliding friction and wear against Cr12MoV steel is transformed from severe adhesion wear and oxidation wear to slight abrasive wear,adhesion wear and oxidation wear with increasing in TiC content.关键词：Titanium Matrix Composites;TiC Particle-reinforced;Wear Resistance
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发布时间：2023-12-18 - 摘要：Damping capacity of the test alloys was tested by MDA 8Q00 dynamic mechanical analyzer.The effects of rare earth element Nd on the damping capacities and microstructure of ZK60 magnesium alloys were analyzed,and the damping properties of the alloys at as-cast,as-solution and as-extruded were compared.The results show that the grains in the alloy at as-cast state are refined from 100μm to approximately 35μm and the microstructure of the alloy is changed from two phases ofα-Mg+MgZn to three phases ofα-Mg+MgZn+MgNdZn owing to the addition of rare earth element Nd.The lengths in the weak pinning points are shortened and the strain independent damping capacities of the alloy are reduced because of solid solution of Nd atoms.However,the strain dependent damping values of the alloy with Nd are improved by a large number of movable dislocations produced by interaction between MgNdZn andα-Mg matrix.In moderate strain amplitude range(1×10-4≤ε≤4×10-4),damping properties of ZK60 magnesium alloys at as-cast,as-solution and as-extruded,containing rare earth element Nd,are higher than that of alloys without Nd,respectively.关键词：Rare Earth Element Nd;ZK60 Magnesium Alloy;Microstructure;Damping Property
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发布时间：2023-12-18 - 摘要：Two kinds of AuSn20 eutectic alloy solder ribbons were prepared by a common casting-rolling process and a rapid solidification-rolling process.The microstructure,phase constitution,composition distribution,melting characteristics and soldering strength of the AuSn20 alloys prepared were analyzed comparatively using optical microscopy,scanning electron microscopy,X-ray diffraction,energy dispersive spectroscopy,differential scanning calorimetry and a MTS ceramic testing system.The results show that the microstructure of AuSn20 eutectic alloy solder ribbons prepared by a rapid solidification-rolling process presents finer and more uniform compared with that of ones by common casting-rolling process.The solidus and liquidus are reduced by 4.9 ℃ and 7.4 ℃,respectively,and the melting range is narrowed by 2.5 ℃.In addition,the wettability and shear strength of the solder joints are increased by10.96% and 19.02%,respectively.关键词：Papid Solidification;AuSn20 Solder;Microstructure;Properties
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发布时间：2023-12-18 - 摘要：The research status of solidified structure of metal by physical fields was described briefly,and based on the single physical field,several newly developed compound physical fields on effects of solidified structure were expounded.Due to the good control effect of the compound physical fields,in order to obtain the desirable grain refinement,some problems in development in compound physical fields were pointed out.Finally,future of compound physical fields was also prospected.关键词：Compound Physical Fields;Solidification Structure;Grain Refinement
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发布时间：2023-12-18 - 摘要：The structure and technological characteristics of aluminum alloy box were analyzed.The gating system of sand casting was designed.The casting process of aluminum alloy box body was simulated by AnyCasting software,and the position and reason of casting defect were visualized.Based on the simulated results,process scheme was modified by improving gating system,setting cold iron and riser reasonably to reduce the casting defects.Finally,an optimized casting process scheme was designed sucessfully.关键词：Aluminum Alloy;Sand Casting;Numerical Simulation;Process Optimization
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发布时间：2023-12-18 - 摘要：To solve the problems of quality inconsistency of the aluminum alloy engine block,mathematical model with the characteristic of nonlinearity,strong coupling and uncertainty was established for the metal mold casting solidification process.The cloud model can realize the uncertain transformation between qualitative description and quantitative numbers and it is combined with PID control method to achieve the optimal temperature control in the solidification process.To test and verify the superiority of the control algorithm,the temperature control system experimental platform was established to compare tests among the manual operation,PID control and cloud model PID control algorithm.The experimental results reveal that the cloud model PID has an advantage of following ability and stability.关键词：Solidification Process;Uncertainty;Cloud Model;PID;Reasoning Mechanism
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发布时间：2023-12-18 - 摘要：Porosity defect is most formed likely in the die-casting parts with complex shape and uneven thickness.It is effective way to improving quality of die casting parts by local squeeze process-assisted HPDC.The method and structure of local squeeze process was analyzed.The influence of four kinds of parameters for applying local squeeze process on die casting part quality was presented,including squeeze depth,pressure,squeezing delaied time and time of duration.Two castings produced by local squeeze process-assisted HPDC were presented to verify the application effect.关键词：Die Casting;Local Squeeze Process;Shrinkage;Gas Hole
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发布时间：2023-12-18 - 摘要：Aiming at structural characteristics,the mould was designed with feeding at side blank sealing face or side of assembled face（enhanced rib）,and the effects were analyzed.The resultant mould design was determined.The scrap shape was described.Through modifying process and management,countermeasures were presented,focusing on eliminating gas hole in the castings to decrease scrap rate.关键词：Pouring Channel;Exhausting and Overflow Slot;Die Casting Die
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发布时间：2023-12-18 - 摘要：Effects of squeezing melt temperature on microstructure and mechanical properties of Al-5.0 Cu-0.6 Mn-0.5 Fe-0.1 Ti-0.1 RE alloy prepared by squeeze casting were investigated by tensile test,image analysis and scanning electron microscope.The results show that with the squeezing melt temperature of650 ℃,the ultimate tensile strength and elongation of the alloy reach 299 MPa and 17.5%,respectively,while those of the alloy are increased slightly with the squeezing melt temperature from 590 ℃ to650 ℃,which can be attributed to the decrease of the dendritic arm spacing ofα-Al phase,the second intermetallic phases,the volume of casting defects and the increase of volume fraction of fine structure in bi-modal structure resulted from the increase of solidification liquid phase under applied pressure.关键词：Aluminum Alloy;Squeeze Casting;Squeezing Melt Temperature;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The high vacuum die casting of the car automotive chassis structural parts was analyzed,and the die casting technology development and application of the heat-treatable Al-Si-Mg-Mn high strength aluminum alloy car automotive chassis structural parts were described.The numerical simulation method was adopted to analyze the flow and filling of the aluminum alloy liquid and the distribution of the casting defects with different pouring gates.In addition,the effects of gating system were analyzed,such as the comb-shaped pouring gate,the sector pouring gate,pouring concentrate and pouring disperse,long pouring gate and short pouring gate,on the filling process,filling temperature,the filling velocity and the drag pressure.The optimized pouring system and exhausted system was determined to reduce greatly the mold development period.关键词：Car Automotive Chassis Structural Parts;High Vacuum Die Casting;Numerical Simulation;Gating System
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发布时间：2023-12-18 - 摘要：The filling and solidification process was simulated by Magma software for aluminum alloy chain cover,and die casting process were optimized as follows:pouring temperature of 670 ℃,mold preheating temperature of 150 ℃,slow injection velocity of 0.3 m/s and the high injection velocity of 3 m/s.Through adopting the optimized parameters,the qualified aluminum alloy chain cover was produced successfully,which verified the rationality of the simulated results.关键词：Die Casting;Numerical Simulation;Chain Cover
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发布时间：2023-12-18 - 摘要：Processing measures were described of solving shrinkage porosities（holes）which were formed as a result of over-thermal of isolated hot spot and poor heat dissipation of mold shell in investment castings.Some measures were adopted to ensure smooth feeding channel and uniform temperature distribution to realize sequential solidification of filling process,such as partial mold shell chilling,insulation+partial mold shell water quenching,insulation+partial spraying water treatment,adding feeding rib,setting riser subsidiary,modifying pouring-riser design,improving heat dissipation condition and avoiding localized over-heat,successfully eliminating shrinkage porosities（holes）tendency.关键词：Water Quenching;Hot Spot;Feeding Channel;Temperature Field;Feeding Rib
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发布时间：2023-12-18 - 摘要：Aiming at the problem of TiAl alloy’s low room temperature plasticity and cracking tendency,investment casting process of Ti-48 Al-2 Cr-2 Nb alloy was investigated by the combination methods of oxide ceramic shell,VAR an centrifugal casting.TiAl alloy thin-walled circular component has been manufactured successfully with a diameter of 260 mm and wall thickness of 1.53.0 mm in the 80%area after the optimization of gating system and pouring process.Through the nondestructive testing of metallurgical quality,absence of crack and shrinkage cavity defects can be observed.关键词：TiAl Alloy;Investment Casting;Gating System;Pouring Process
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发布时间：2023-12-18 - 摘要：The Al-16 Si-7 Ti composite tubes reinforced with in-situ primary particles were prepared by centrifugal casting.Microstructure in the composites prepared was observed and analyzed by SEM,EDS and OM,and the effects of heat treatment on the microstructure and properties of the composites were investigated.The results show that the centrifugal casting of Al-16 Si-7 Ti composites forms three layer structures,the outer layer containing a large number of primary TiAlSi/Si particles（the enhancement phase）,the middle layer of particle free matrix zone,and the inner layer with a very small amount of primary Si particles.After heat treatment,the morphology change of primary TiAlSi phase can be ignored and the sharp corners of the primary Si particles tends to be spherical,and the eutectic structure is dissolved and presents a punctate distribution.The hardness value of the aged alloy reaches HRB 67.5.The wear resistance of the composites after aging treatment is also better than that of the as cast ones,and the volume wear of the aged composite is reduced by 65%.关键词：Al-16Si-7Ti Composites;Heat Treatment;Structures and Properties
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发布时间：2023-12-18 - 摘要：The surface of aluminum alloy was treated by zincate process and QJ207 brazing process.The results reveal that both methods can remove effectively the oxide film and improve the wettability of liquid magnesium on the surface of solid aluminum alloy.The interfacial structure and properties of Mg/Al-20 Si bi-metal liquid-solid compound casting with different rare earth Nd contents in magnesium alloy were analyzed by means of SEM,XRD,EPMA,mechanical testing machine and microhardness tester.With the increase of Nd contents,Al-Nd phase is formed in the interface of composite materials,which inhibits the production of intermetallic compounds,and Al-Nd phase is gradually transformed from acicular Al11 Nd3 phase to blocky Al2 Nd phase.When content of Nd reaches 1%,the maximum shear strength of 22.28 MPa can be obtained.关键词：Zincate;Brazing Flux;Rare Earth Nd;Interface;Shearing Strength
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发布时间：2023-12-18 - 摘要：The temperature dependence of elastic properties,elastic anomalies and energy loss associated with structure relaxation of Zr-based bulk metallic glasses（BMGs）Zr60.6Cu18.6Ni11.7Al9.1and Zr54.45Cu29.7Al9.9Ni4.95Y1 was investigated using dynamic mechanical analysis（DMA）.The glass transition temperature Tgand the crystallization temperature Txwere determined to be 689K,654K,733Kand 724Kby differential scanning calorimetry（DSC）.X-ray diffraction（XRD）analysis indicates that both the structures exhibit amorphous.DMA results indicate that kinks or valleys in the storage moduli occur near Tg.Peaks of the loss moduli and the loss factor occur near Tg.With the increase of the frequency,the peak amplitudes are decreased,and the peak temperature basically remains the constant value.βrelaxation is indicated by the excess wings.关键词：Metallic Glasses;Dynamic Mechanical Analysis;Elastic Properties;Structure Relaxation
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发布时间：2023-12-18 - 摘要：The effects of different pretreatments（homogenization,peak ageing and hot extrusion）and cold-rolling true strain on the mechanical properties of Al-0.2 Sc-0.02 Zr-0.02 Yb alloy were investigated.The results reveal that the peak aging temperature（330℃）is independent on the cold rolling.The mechanical properties of three kinds of pretreating+cold rolling+ageing alloys are increased with increasing in the cold-rolling true strain,which approximately follows the Hollomon’s formula.The corresponding strengthening coefficient K and strengthening exponent n canbe obtained obtained by fitting method.Among the three kinds of pretreatments+cold-rolling+peak ageing alloys,the nis the maximum for homogenization,secondary for hot extrusion,and the minimum for peak aging.For the homogenization+cold rolling+ageing alloys,the nis increased firstly and then decreased with increasing in ageing temperature,and the maximumnis presented at 280 ℃.关键词：Al-Sc-Zr-Yb Alloys;Mechanical Properties;Pretreatments;Cold Rolling;Ageing
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发布时间：2023-12-18 - 摘要：The casting process of complex thin-walled frame aluminum alloy castings was described.Based on the three-box modeling,the required sand core structure was designed,and the middle box molding process was simplified.A round bottom-pouring gating system was designed.The filling and solidification process of the castings were visualized with the help of the ProCAST software.Based on the position distribution and size of the shrinkage cavities and porosities,by setting a riser,insulating sleeve and cold iron at the predicted defects position,effective filling can be realized,and the casting defects such as shrinkage cavities and porosities can be basically eliminated.关键词：Aluminum Alloy;Casting Method Design;Numerical Simulation;Process Optimization
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发布时间：2023-12-18 - 摘要：The influence of the type,addition of Al-5Ti-B refiner and refining process on the structure and mechanical properties of ZL205Aalloy was investigated by OM,SEM and tensile testing.When the TiB2phase in the Al-5Ti-B refiner is aggregated,the refinement effect can induce inhomogeneity.In addition,the coarse Al3Ti in the refiner will be resided in the alloy and greatly reduce the elongation.With Al-5Ti-B refiner of 0.25%,the refinement effect of ZL205Aalloy is desirable and the mechanical properties reach the satisfied values,where the yield strength,tensile strength and elongation reach 378MPa,455 MPa and 8.9%,respectively.With using C2Cl6 purifying,the"toxic"reaction of Al-5Ti-B refiner can lead to the aggregation and deposition of TiB2 particles.The stability of TiB2phase can be guaranteed by using Ar purifying and controlling the purifying time.关键词：ZL205A Alloy;Al-Ti-B Refiner;Purifying Process;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The macro and micro feature,chemical composition of fracture surface,metallography and hardness of burst failure aluminum alloy T-shaped tube were analyzed by SEM,EDS and optical microscope.The results reveal that the failure fracture is characterized by ductile fracture.Hydroforming Tshaped tube has a higher compressive strength compared with tube billet due to working hardening,and the shoulder is severely thinned under the internal pressure.What’s more,the instantaneous fracture was formed at the shoulder of T-shaped tube and then extended to both ends.The shoulder thickness of Tshaped tube should be appropriately increased to improve pressure resistance under the working environment.关键词：Aluminum Alloy T-shape Tube;Bursting Test;Failure Analysis;Fracture Morphology
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发布时间：2023-12-18 - 摘要：The effects of Zr、Sc element on corrosion resistance of Al-Cu-Mg-Ag-Ti alloy were investigated by slow tensile,intergranular corrosion and electrochemical testing.The results reveal that the corrosion resistance of the alloy can be improved by adding Zr elements.Stress corrosion sensitivity factor(Iscc)of Zr-containing alloys is lower than that of the Zr-free alloy.However,the compound addition of Zr and Sc can not further improve the corrosion resistance of the alloy.The addition of Zr can inhibit the recrystallization and make the precipitate free zone narrower,greatly improving the corrosion resistance of Al-Cu-Mg-Ag-Ti alloy.The comprehensive performance of Al-Cu-Mg-Ag-Ti alloy with 0.19%Zr presents the desirable comprehensive behavior,where the lowest depth of intergranular corrosion and the smallest Iscc as well as the highest tensile strength can be obtained.In addition,the yield strength and tensile strength of the alloy with 0.19%Zr reach 466 MPa and 518 MPa,respectively.关键词：Al-Cu-Mg-Ag-Ti;Zr;Intergranular Corrosion;Stress Corrosion Resistance;Electrochemical Tests;Tensile Strength
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发布时间：2023-12-18 - 摘要：Normal and square segregation area of TC18 titanium forged bar were analyzed.EBSD analysis was employed to quantitatively characterize the micro features of both area.The results indicate that the microstructure constitution is similar.However,due to the influence of Fe and Cr segregation,theβtransus temperature is decreased which is benefits for the precipitation and nucleation ofαphase.Consequently the overallαphase content is higher.Besides,αphase is distributed intensely from 0 to 40μm2.The cooling rate of square segregation area is higher than normal area,thus the 010μm2 smallαparticle is obviously higher than normal area with a higher globularization ratio.The results show that forged TC18 bar is not qulified as rotating part for long-term use.关键词：TC18;Forged Bar;Square Segregation;EBSD
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发布时间：2023-12-18 - 摘要：Internal defects is easily formed in aluminum alloy wheels during production,and it’s quality needs to be evaluated through X-ray non-destructive testing technology.The traditional detection method is dependant on manual evaluation,which detects qualitatively by experience with high strenght work and lack objective data.An automatic detection method based on digital image processing technology was proposed,which could extracts defect area by using image segmentation algorithm and calculating the geometric parameters of the defect to achieve its quantitative results.The experimental results reveal that the proposed method can be used to assist the manual evaluation and meet the needs of production test.关键词：Automobile Hub;Defect Detection;Image Processing;Manual Detection;Automatic Detection
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发布时间：2023-12-18 - 摘要：The laser heat treatment was used to replace the furnace heat treatment of the traditional retrogression re-aging（RRA）in the regression stage in order to achieve a better effect of short-time high temperature regression treatment.The heat treatment process was presented as follows:the heating temperature of the pre-aging stage at 120 ℃for 16 hwith laser heat treatment in the regression stage,where the laser power is 650 Wand the scanning speed is 2 mm/s with the re-aging stage at 120 ℃for24 h.The high temperature tensile tests of the alloy with heat treatment were carried out.The results show that with the increase of temperature,the strength loss of the alloy at high temperatures is severe,while the elongation is increased greatly,and the fracture can form obvious necking.The high temperature properties of the alloy after LRRA heat treatment are superior to those of ones after RRA heat treatment.The advantage of LRRA heat treatment becomes more obvious with the increase of temperature.关键词：7075 Aluminum Alloy;Laser Heat Treatment;Retrogression and Re-aging;High Temperature Tensile Properties;Mechanical Properties
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发布时间：2023-12-18 - 摘要：SLS,SLA,FDM and machining technologies were used to prepare side frame characters in railway vehicle with polyamide,photopolymer,PLA and ABS.Meanwhile,small batches of core-making experiments were carried out to validate the suitability of the 3D printing plastic core in railway castings.The results indicate that the strength and wear-resistance of the four kinds of materials can satisfy requirements of sand core production.Dimensional precision and surface quality of the photopolymer core are more desriable.3D printing photopolymer core has the advantages of high processing efficiency,high accuracy,low cost,easy to repair and change the structure and light weight of mould,which is suitable for application to the trial production and small batch production of steel castings.关键词：3D Printing;SLS Technology;SLA Technology;FDM Technology;Railway Castings
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发布时间：2023-12-18 - 摘要：The effects of different annealing temperature and time on the microstructural evolution and mechanical properties of the oxygen free copper tube were investigated by OM,TEM,SEM and universal tensile tester.The results reveal that:the high energy and high density dislocation of the as-deformed sample are evolved into thin dislocation walls,subgrain boundaries and then high angle grain boundaries with annealing at 260 ℃ or 300 ℃for 60 min,resulting in low density dislocation structure.After annealing at 300℃,recovery and recrystallization are fully completed.The tensile strength,yield strength and hardness are decreased with temperature increase,while the elongation is increased.Within the annealing temperature range of 300 ℃to 460 ℃,the change of mechanical properties of the copper tube can be ignored.Increasing the annealing time at 300 ℃from 10 min to 60 min,recrystallization is induced gradually,and the tensile strength,yield strength and hardness are decreased,while elongation is increased.With annealing for 60 min,recrystallization is finished,and the tensile fracture morphology is changed from quasi-cleavage surface,tearing edge and dimple characteristics to equiaxial dimples.Compared with those of as-deformed sample,the tensile strength,yield strength and hardness of the copper tube are decreased by 39%,68.5%and 53.1%,respectively,and the elongation is increased from1.2%to 50%.With annealing time more than 60 min,the grain size is increased slightly before reached a stable value,showing an insignificant effect on the mechanical properties.关键词：Copper Tube;Annealing;Microstructure;Mechanical Properties
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发布时间：2023-12-18 -
Effects of Pulsed Magnetic Field on Solidification Structure and Mechanical Properties of ZA27 Alloy
摘要：The effects of different pulse parameters and cooling conditions on the solidified structure and mechanical properties of ZA27 alloy were investigated.The results show that the solidified structure and mechanical properties of the alloy can be improved by controlling the parameters of the pulsed magnetic field and cooling conditions.When the pulse voltage is at 0300 V,with the increase of pulse voltage,the primary phase in the ZA27 alloy is transformed gradually from coarse dendrite to fine spherical or rosette structure,and the compressive strength is increased gradually,where the maximum strength is increased by up to 39.6%,compared with that of the alloy without pulse magnetic field treatment.When the pulse frequency is at 110 Hz,with the increase of pulse frequency,the primary phase in the alloy is refined gradually,and the compressive strength is increased gradually.With the increase of pouring temperature at 490580℃ or the mold temperature at 10400℃,the primary phase in the alloy is refined at first and then coarsened,and the turn point are 520 ℃ and 200 ℃,respectively.As a whole,with the pouring temperature or mold temperature increase,the compressive strength of the alloy is increased gradually.关键词：ZA27 Alloy;Pulsed Magnetic Field;Solidified Structure;Mechanical Properties- 2
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发布时间：2023-12-18 - 摘要：The electrolysis effects of Ni-based alloys in different electrolytes were investigated.Three kinds of Ni-based alloys,including N6,Cr20 Ni80 and 4 J43,were analyzed by electrolysis in single oxysalt electrolyte and mixed oxysalt electrolyte,respectively.Non-metallic inclusions in the alloys were separated and observed by scanning electron microscope.Meanwhile,anode polarization curves of N6,Cr20 Ni80 and 4 J43 in different electrolytes were obtained by electrochemical workstation.Morphology of inclusions separated was observed by SEM（scanning electron microscopy）.The results reveal that nonmetallic inclusions are separated smoothly from Ni-based alloys in mixed oxysalt electrolyte,and the pH value keeps at approximately 5 during electrolysis process,presenting the satisfied transpassivity.SEM analysis shows morphology change absence of non-metallic inclusions separated.The mixed oxysalt electrolyte can improve the precision of non-metallic inclusions separation from Ni-based alloys.关键词：Ni-Based Alloys;Electrolytic Extraction;Electrolyte;Non-metallic Inclusions
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发布时间：2023-12-18 - 摘要：High energy shot peening was used to treat the surface of GH4169 alloy with 2 mm in diameter stainless steel projectile.The effects of different shot peening time（1 min,3 min,5 min and 10 min）on the surface morphology,surface microstructure,surface roughness and microhardness of the GH4169 alloy were investigated.The results reveal that the surface integrity of the alloy is decreased with the increase of the shot peening time,while the shot peening layer,the microhardness and the surface roughness are increased with increasing in shot peening time.With shot peening for 10 min,the thickness effect of shot peening layer of GH4169 alloy can reach 190μm,and the surface hardness is 389 HV,increased by 35% compared with that of the original sample.关键词：GH4169 Alloy;Shot Peening;Microstructure;Surface Performance;Shot Peening Time
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发布时间：2023-12-18
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