最新刊期
卷 38 ， 期 4 ， 2018
- 摘要：The oxidation behavior of DZ125 alloy at 1 100℃ was investigated,and the formation and failure mechanisms of the oxide film were evaluated.The results show that the oxide film formed on DZ125 alloy has a three-layer structure,mainly composed of a Cr2O3 outer layer,a NiO and NiCr2O4 middle layer and an Al2O3 inner layer.The oxidation kinetics of DZ125 alloy at 1 100℃follows a parabolic law.During the oxidation process,high activity elements of Hf and Ta segregated at the grain boundaries of the alloy can be oxidized preferentially,which provide the inward diffusion path for oxygen and lead to the interior oxidation of the alloy.With the prolongation of oxidation time,the oxide film is cracked and failure under the action of stress.关键词：DZ125 Alloy;Microstructure;Oxidation;Failure Mechanisms
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发布时间：2023-12-18 - 摘要：The influences of the oxidation conditions,microstructure and composition on the oxidation resistance of Ti-Al alloys were investigated.The results reveal that Ti-48 Al-2 Cr-2 Nb alloy exhibits a desirable oxidation resistance and a kind of four-layered structure exists in the oxide films at 700 and 800℃.With the isothermal oxidation test for 100 hat 800℃,the mass increment of Ti-48 Al-2 Cr-2 Nb alloy samples with three kinds of microstructures is increased from the sample with a duplex structure to the one with a nearly lamellar structure,and then to the sample with full lamellar structure.The mass increment of Ti-Al alloys with three compositions is increased from Ti-45 Al-8 Nb-0.2 W-0.1 B-0.1 Yalloy to Ti-46.5 Al-2.5 V-1 Cr alloy,and then to Ti-48 Al-2 Cr-2 Nb alloy.The Ti-45 Al-8 Nb-0.2 W-0.1 B-0.1 Yalloy sample with duplex structure shows a low oxidation mass increment of 4.8 g/m2 after the isothermal oxidation test for 100 hat 800 ℃.关键词：Ti-Al Alloy;Oxidation Resistance;Microstructure;Composition
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发布时间：2023-12-18 - 摘要：The effects of die casting processing parameters,such as pouring temperature,mold temperature and injection speed,on microstructure and mechanical properties of AZ91-0.5 Nd-0.3 Y-0.3 La alloy were investigated based on orthogonal experiment.The results show that the order of important factor is followed as:pouring temperature,mold temperature and injection velocity.The optimized die casting process parameters of alloy are presented as:pouring temperature of 685 ℃,mold temperature of 240℃ and injection velocity of 4.0 m/s,where the ultimate tensile strength,yield strength and elongation reach 292 MPa、186 MPa and 9.7%,respectively.关键词：AZ91-Nd-Y-La Alloy;Die Casting;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Bending properties,tensile properties and hardening precipitates of 6082-T6 aluminum plates were investigated under production conditions,and the relation equation between tensile property and bending property was attempted to be established and verified.The results show that the plate bending property can be evaluated quantitively by the elongation,and the equation among critical elongation（δ）,plate thickness（t）and bending radius（r）followsδ=（t/2）（t/2+r）.The higher elongation（>17%）can be obtained by adopting the 155℃×（416）h under-aging process with the combination of clusters and finest need-likeβ″precipitates,resulting in the good plate bending property while keeping tensile properties.In addition,the tensile property data in 6082 plate production of two aging processes（170℃×12 h、155 ℃×12 h）was compared,and it was verified that the higher elongation and tensile strength could be obtained by adopting the 155 ℃×12 haging treatment.关键词：6082Alloy;Aging;Crack;Bendability;Elongation
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发布时间：2023-12-18 - 摘要：Taking bauxite and talcum powder as refractory aggregates,sodium bentonite and CMC as suspending agent,hexametaphosphate and water glass as compound binder as well as water as the carrier with appropriate antifoaming agent and surfactant,bauxite coating was prepared,in which CMC is0.5%,water glass is 5%and sodium hexametaphosphate is 6%（the amount of each additive is the mass percentage of aggregate）.By changing the amount of sodium bentonite,based on testing the coating density,pH value,viscosity,suspension,strength,leveling,smearing and dripping properties,the effect of sodium bentonite on the coating performance was analyzed.The results reveal that the coating has the desirable comprehensive performance with 5% sodium bentonite.关键词：Sodium Bentonite;Coating Behavior;Bauxite Coatings
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发布时间：2023-12-18 - 摘要：Mg-xZn-3 Y-0.7 Zr alloy was prepared by low-pressure casting.Evolution of the microstructure of Mg-xZn-3 Y-0.7 Zr alloy was observed by optical microscope,scanning electron microscope and differential thermal analysis.The heat treatment process was optimized to improve the mechanical properties through controlling secondary phase distribution in the Mg alloy.The results indicate that the as-cast microstructure of Mg-5 Zn-3 Y-0.7 Zr alloy is composed ofα-Mg and W-Mg3 Zn3 Y2 phase.The W phase with net-like structure is distributed along the grain boundary.With the addition of 8% Zn,dendrites in as-cast alloy are obviously increased,and I-Mg3 Zn6 Y phase appears.After T6 heat treatment,the IMg3 Zn6 Y phase disappears,and the plate-like eutectic structure of W phase is broken,however,fishbone lamellar eutectic structure is reserved at triangle grain boundary.The tensile test shows that the ultimate tensile strength,yielding strength and elongation of as-cast Mg-5 Zn-3 Y-0.7 Zr alloy reach 223.8 MPa,124.9 MPa and 7.3%,respectively.Effects of T6 heat treatment on mechanical properties of the Mg-5 Zn-3 Y-0.7 Zr alloy can be ignored.After T6 heat treatment,the mechanical properties of Mg-8 Zn-3 Y-0.7 Zr alloy are improved greatly.The ultimate tensile strength,yielding strength and elongation reach 263.3 MPa,207.9 MPa and 2.2%,respectively.The fracture mechanism of Mg-5 Zn-3 Y-0.7 Zr is characterized by quasi cleavage crack with tearing ridge,while the Mg-5 Zn-3 Y-0.7 Zr alloy is characterized by cleavage fracture with absence of dimple.关键词：Magnesium Alloy;Heat Treatment;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The influence of 0.15% WS-1 no silicon modifier on microstructure and properties of austenitic heat resistant stainless steel was tested.The results show that the modification treatment has a good effect on the inhibition of crystal growth,the refinement of microstructure and the increase of mechanical properties of the alloy.The tensile strength,yield strength and elongation of the alloy with 0.15%modifier reach 463.6 MPa、276.6 MPa、6.91%,respectively,which are increased by 44.3%、15.3%、77.2%,compared with those of the alloy without WS-1 modifier addition,meeting requirement of mechanical properties.关键词：Modification Treatment;Austenitic Heat Resistant Stainless Steel;Microstructure;Mechanical Property
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发布时间：2023-12-18 - 摘要：The effects of laser power,scanning speed and hatch spacing on the quality,microstructure and mechanical properties of SLM formed Ti-6 Al-4 V（TC4）powder parts were investigated by orthogonal experimental method.The energy density was introduced to confirm optimal forming domain of TC4 power in SLM.The results reveal that with the increase of energy density,the SLM forming performance of TC4 powder exhibits a tendency of improvement firstly and then worse.The optimum forming processing parameters are presented as follows:laser power of 400 W,scanning speed of 1 8002 200 mm/s,hatch spacing of 0.08 mm and spreading thickness of 0.05 mm.关键词：SLM;TC4 Alloy;Energy Density;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The application of SLA 3 Dprinting in investment casting industry was introduced,and the special process was described.Dwelling shell defects of thin-walled investment castings were paid attention,and countermeasures were presented for the practical product.The products have the advantages of high dimensional precision,surface smooth and enviromental friend.The SLA 3 Dprinting can shorten greatly the development time and reduce R&D costs,and enhance significantly the competitiveness of enterprises.关键词：SLA;3DPrinting;Investment Casting;Dwelling Shell
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发布时间：2023-12-18 - 摘要：The damping mechanism,the materials system and reinforce microstructure of magnesium matrix damping composites were described.The preparation and post treatments of magnesium matrix damping composites were summarized.Based on the review and analysis of the research progress,the prospects of the developing directions of magnesium matrix damping composites were proposed.关键词：Magnesium Matrix Composites;Damping Properties;Damping Mechanism;Material System
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发布时间：2023-12-18 - 摘要：Al-7 Si-0.3 Mg aluminum-alloy front sub-frames side beam with hollow structure was designed.Through optimizing the product structure design,gravity casting technology was adopted,and the process parameters were optimized by numerical simulation.In addition,internal quality and mechanical properties of the castings were analyzed by X-ray detector and universal tester.The results reveal that the gravity casting aluminum alloy sub-frame side beam casting can meet fully the standard requirement.关键词：Front Sub-frame Side Beam;Gravity Casting;Aluminum Alloy;Numerical Simulation
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发布时间：2023-12-18 - 摘要：A method based on the inverse heat transfer to obtain the interfacial heat transfer coefficient was established.Take the cooling curve of the iron castings as input data,it can obtain the heat transfer coefficient between the iron castings and mold in lost foam casting.When the temperature of the mold is20 ℃,the coefficient is followed as the equation h（t）=182.8-182.1×(7.23×10-5)t,while the temperature is 50 ℃,the coefficient is followed as h（t）=181.7-237.1×(1.45×10-4)t.The temperature field was simulated based on the coefficient obtained by the method.The results reveal that compared with that of ones with empirical constant,the simulated results are well agreement with the practical temperature field.关键词：Inverse Heat Transfer Method;Interfacial Heat Transfer Coefficient;Temperature Field;Iron Castings
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发布时间：2023-12-18 - 摘要：Design scheme of a communication filter part was simulated by the Magmasoft,and origination of gas hole was analyzed.Corresponding countermeasures were adopted to solve the defect,which could provide reference for the development of the similar products.关键词：Die Casting;Gating System;Exhaust System;CAE Simulation Analysis
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发布时间：2023-12-18 - 摘要：A new low-rare-earth Mg-4 Al-0.5 RE（0.25 Y+0.25 Ce）-0.8 Ca alloy was designed.The microstructures of squeeze-cast AE42 and Mg-4 Al-0.5 RE-0.8 Ca alloys were investigated,and the effects of different corrosion environment on the corrosion behavior of Mg-4 Al-0.5 RE-0.8 Ca alloy were analyzed.The results reveal that dendritic Al-RE in the AE42 is converted into acicular Al-RE in the Mg-4 Al-0.5 RE-0.8 Ca alloy,and the new Al2 Ca phase can be generated due to the Ca addition.Corrosion tests reveal that the corrosion rate is increased with the increase in temperature and chloride ion concentration.The surface film is destroyed at high temperature and passivated phenomenon is absent,while the alloy at high NaCl concentration presents the passivated phenomenon.The new alloy exhibits good corrosion resistance,which is attributed to the lower potential difference between precipitation andα-Mg matrix as well as homogeneous dense corrosion film.关键词：Squeeze Casting;Mg-4Al-0.5RE-0.8Ca;Microstructure;Corrosion Behavior
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发布时间：2023-12-18 - 摘要：The ProCAST software was used to simulate the filling and solidification process of alloy wheels with complex wheel faces,and occurrence of the defects such as porosity,shrinkage porosity and shrinkage cavity was predicted and the origination of defects was analyzed.The simulated results reveal that when the initial lift velocity of metal liquid is reduced to 65 mm/s,porosity defects near the casting gate are relieved obviously.In addition,by adjusting the water flow velocity of the side mold water cooling system to 0.75 m/s and establishing the feeding channel on both sides of the spokes,the area of hot spot at the connection between the spoke and the rim is reduced and the defects are eliminated.The optimization scheme was adopted for producing trial-wheel.The results reveal that wheel surface exhibits clear with good mechanical properties and absence of significant defects,meeting the standard requirements.关键词：Complex Wheel Faces;Low Pressure Die Casting;Numerical Simulation;Process Optimization
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发布时间：2023-12-18 - 摘要：M70 mullite refractory aggregate steel-based alcohol-based coating fragments after pouring was analyzed by the scanning electron microscopy and energy spectrum analysis.The results indicate that the coating in the pouring process contacts with the molten steel,which leads to the coating temperature closed to the refractory aggregate temperature,so chemical and physical changes in coating occurs to generate dense structure.The dense structure can prevent the infiltration of molten iron into the sand,which prevent effectively the formation of sticky sand to ensure the quality of the castings.关键词：Alcohol-base Coating;Mullite;Sticky Sand;Peeling Mechanism
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发布时间：2023-12-18 - 摘要：The interface reactions between DD6 single crystal superalloy and ceramic shells were investigated by scanning electron microscopy（SEM）and energy dispersive spectroscopy（EDS）.The results show that the interface reaction products of DD6 superalloy and Zr mold are composed of Al2O3,HfO2,oxide Nb/Ta and Si.The interfacial reactions are enhanced due to the decomposition of ZrSiO4 at high temperature,and the reaction products are adhered to the face coat of the mold to generate Al2O3 reaction layer with 58μm in thickness at the mold side.The defects can be observed on the surface of the alloy simultaneously.The"reaction pitting"model was established by analyzing the reaction process of"Al element oxidation-ZrSiO4 decomposition-a low melting point of Si-rich liquid phase formation-Al2O3 particle precipitation".关键词：DD6Single Crystal Superalloy;Zircon Ceramic Mold;Interface Reaction
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发布时间：2023-12-18 - 摘要：Al-Mg3Sb2 composite coating was prepared on the surface of magnesium alloy AZ31B by thermal spraying,and the influence of friction frequency on tribological properties of the coating in dry and3.5% NaCl solution was analyzed.The cross sectional morphology and phases of the coating were observed by SEM and XRD.The open circuit potentials and friction coefficients with different friction frequencies of the coating were measured by a corrosion abrasion tester.The sectional profiles and wear volume of wear tracks on Al-Mg3Sb2 coating were tested by ultra deep field 3D microscope.The results show that the open circuit potentials of coating are decreased with the increase of friction frequencies in 3.5%NaCl solution.The friction coefficients of the coating are decreased and the wear rates are increased with the increase of frequency under two conditions.And the friction coefficients and wear rates of the coating in 3.5%NaCl solution are all lower than those of ones under dry condition.The spalling of wear scar of the coating under dry friction condition is more and more obvious with the increase of friction frequency.In the 3.5%NaCl solution,the surface of the wear scar exhibits smooth,and a small amount of spalling pits appear with the increase of friction frequency.关键词：AZ31B Magnesium Alloy;Al-Mg3Sb2 Coating;Friction Frequency;Dry and Wet Conditions
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发布时间：2023-12-18 - 摘要：Influences of some treating ways,such as untreated,alloying treatment of P and La,ultrasonic treatment and compound treatment of ultrasonic and alloying,on solidification structure and mechanical properties of Al-20Mg2Si were investigated.Effects of ultrasonic power,ultrasonic treatment time and ultrasonic treatment temperature on size of Mg2Si phase and mechanical properties of the alloy were investigated under the condition of compound treatment.The results reveal that after compound treatment,the solidification structure and mechanical properties of the alloy are improved remarkably,and the effects are superior to those of single alloying treatment or ultrasonic treatment.Compared with untreated samples,the size of the primary Mg2Si phase is decreases by 68%,and the tensile strength and elongation of the alloy are increased by 62.3%and 47%,respectively.With the increase of ultrasonic power,the size of primary Mg2Si phase is decreased gradually,and the mechanical properties are increased gradually.With the increase of ultrasonic treatment time,the size of primary Mg2Si phase is decreased at first and then increased,however,the mechanical properties of the alloy are increased gradually.With the increase of ultrasonic treatment temperature,the size of primary Mg2Si phase is decreased at first and then increased,and the change rule of mechanical properties of the alloy is corresponded with it.关键词：Ultrasonic Treatment;Alloying Treatment;Al-20Mg2Si Alloy
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发布时间：2023-12-18 - 摘要：The microstructure and phase composition of Cu/Al composite interface were analyzed by scanning electron microscopy（SEM）and energy dispersive spectroscopy（EDS）for Cu/Al composite conductive head prepared by solid-liquid composite method.The shearing bond strength,microhardness,interfacial conductivity and corrosion resistance of the Cu/Al composite interface were expounded by means of shearing test,microhardness test,eddy current conductivity meter and electrochemical tests.The results reveal that the interface of Cu/Al composite interface is composed of a mixture of a large number of intermetallic compounds and the Al matrix,and the average width of the interfacial transition layer reaches approximately 500μm,in which there exists uneven distribution and large size Hole-like defects and small cracks,so interface bonding strength is only 610 MPa.In addition,corrosion resistance and electric behavior exhibit poor.The comparison of the microstructure and properties of the Cu/Al interface before and after the use of the conductive head shows that the main failure mechanism of the interface of the aluminum-clad conductive head is attributed to the large number of defects in the interface and the thick interface layer.When power is on,the electric resistance heats up severely,which further deteriorates the interface and eventually leads to failure.关键词：Solid-Liquid Composite;Conductive Head;Microstructure;Interfacial Properties
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发布时间：2023-12-18 -
Properties of MIG Welding AZ91D Cast Magnesium Alloy with Aluminum based Welding Wire and Its Effect
摘要：The properties of MIG welding AZ91 Dcast magnesium alloy with φ1.2 mm S301 and φ1.6 mm ER5356 aluminum wire were investigated.The results reveal that two kinds of welding wires can be welded effectively in each welding specification,and a large number of Mg17Al12 brittle phases can be observed in the welded zone,which affect seriously the mechanical properties of the welded zone.The relative content of the Mg based solid solution and the Mg-Al brittle phase in the welded zone is related to the ratio of local Mg and Al.By adding zinc alloy to the welding zone,it is found that zinc can reduce greadly the Mg17Al12 phase in the welded zone,and MgZn2 new phase is precipitated,which promote the growth of magnesium based solid solution.Finally,the comprehensive mechanical properties of the welding zone are improved.关键词：Aluminum Base Welding Wire;Zinc Foil;Mg17Al12 Phase;MgZn2 Phase- 2
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发布时间：2023-12-18 - 摘要：The temperature range of liquid structural transition（LST）for P-type Bi0.4Sb1.6Te3+5%Te alloy was explored by the direct current four-probe method.And then,the parent ingots with different melt states were prepared,respectively,which were subjected to ball milling followed by SPS sintering technology to prepare bulky materials.It is found that the electrical conductivity of the sintered samples after LST is superior significantly to that of the ones without structural transition,while the Seebeck coefficient is decreased slightly,therefore the power factor of the sintered samples is increased slightly.Meanwhile,the induced crystal structure defects in the sample after LST can lead to a strongly scattering of the phonons and thus the thermal conductivity is suppressed significantly.As a result,the sample after LST has the better thermoelectric properties,and the highest ZT value of 1.17 is presented at 120℃.关键词：Liquid Structural Transition;Thermoelectric Materials;Bi0.4Sb1.6Te3;Thermoelectric Properties
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发布时间：2023-12-18 - 摘要：The effects of the solution and aging heat treatment on the microstructure,hardness and tensile properties of ZL101 alloy with adding B and Sb were investigated.The results show that after adding B and Sb,the eutectic silicon becomes small accicular structure from coarse plate,and the long strip primaryα-Al becomes equiaxed structure.At the same heat treatment process,the eutectic silicon in B and Sb modified alloys is spheroidizing fully with the more uniform size distribution,and the precipitated aging phase in the matrix is more dispersed.In addition,the microhardness of the alloy is increased from102.4 HV to 114.6 HV compared with that without modification ones.When the heat treatment process is 540 ℃×6 hsolution+190 ℃×5 haging,the tensile strength and elongation of the B and Sb modified alloy reach 332.8 MPa and 11.73%,respectively,increased by 21.6% and 90.7%,compared with those of the unmodified alloys,and a large number of uniform and fine equiaxed dimple structures appears in the fracture.关键词：ZL101 Alloy;Solution and Aging;Modification;Refinement;B;Sb
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发布时间：2023-12-18 - 摘要：By adding different contents of Cu,Mg and rare earth element Ce to the 2D70aluminum alloys,microstructure of the alloy was analyzed by OM,SEM,EDS.The results reveal that with the increase of Cu content,the Al9FeNi phase in 2D70aluminum alloy is decreased gradually,resulting in the non-equilibrium eutectic reaction.The precipitated eutectic phasesθ-Al2Cu exhibits in the pattern of mesh or Chinese character.With the excessive content of Cu,Al7Cu4Ni phase and Al7Cu2Fe phase which are harmful to mechanical properties of the alloy are precipitated.After the addition of Mg element,excess Cu atoms are trapped to form a lamellar phase S-Al2CuMg,in which the Al9FeNi phase is affected slightly by Cu and hardly reduced.When rare earth element Ce is added,the solute redistribution of the Cu atom appears,so that it can be dissolved fully into the matrix.Thereby,the solid solubility of Cu in the aluminum alloy is increased,and a large amount of refractory phase are absent in the grain boundary,so that the microstructure of the alloy presents uniform with refinement of grain size.关键词：2D70 Aluminum Alloys;Rare Earth;Eutectic Reaction;Solute Redistribution;Solid Solubility
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发布时间：2023-12-18 - 摘要：The effects of Sr-B modification and annealing on the microstructure and thermal conductivity of eutectic Al-Si alloy were investigated by the optical microscope,laser flash apparatus and optical emission spectrometer.The results indicate that the flake-like eutectic Si is transformed into the fibrous structure,and the Al matrix purity is improved through B+Sr compound modification,which obviously enhances the thermal conductivity.The addition order of Sr-B has the remarkable effects on the microstructure and thermal property.The thermal conductivity of 0.02%B+0.03%Sr modified alloy reaches159.5 W/（m·K）,increased by 31.2%than that of the unmodified alloy.With the annealing treatment at 350 ℃for 4 h,the thermal conductivity of 0.02%B+0.03%Sr modified alloy reaches 178.8 W/（m·K）,increased by 10.93%than that of the untreated alloy.关键词：Eutectic Al-Si Alloy;Modification;Annealing;Thermal Conductivity
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发布时间：2023-12-18 - 摘要：Effects of solution treatment on the evolution of microstructure of primary Si and eutectic Si in Al-18 Si alloy prepared by CDS were investigated.The results show that the average size of primary Si in Al-18 Si is decreased significantly with the increase of temperature and time,where primary Si size reaches 20.78μm at 570℃for 6 hsolution treatment.The eutectic Si is also refined from acicular structure to near-spheroidization with increasing in temperature and time,where the average size of eutectic Si phase is decreased from 25.57μm to 5.44μm with more uniform distribution.关键词：Al-18Si Alloy;CDS;Solution Treatment;Si Phase Morphology
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发布时间：2023-12-18 - 摘要：The effects of trace rare earth Ce on microstructure of as-cast and homogenization Zr-containing 7150 alloys were investigated by optical microscope（OM）and scanning electron microscope（SEM）.The results reveal that the trace Zr and Ce can refine greatly 7150 alloy.In the process of homogenization,trace Ce can promote the dissolution of element Mg and Zn into the matrix,however,it can inhibit the homogenization annealing of 7150 alloy.In the treatment process,the Al8Cu4Ce phase with large block polygons can be obserevd,which increases the crack source of subsequent processing.关键词：As-cast Microstructure;Dendritic Segregation;7150 Alloy;Intermetallic Compounds
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发布时间：2023-12-18 - 摘要：The hot compression test was carried out to investigate the deformation behaviors of as-cast AZ91 D magnesium alloy.According to the experimental results,the hot processing maps of the AZ91 D atε=0.4 andε=0.6 were established based on dynamic material model（DMM）theory.The results reveal that the flow stress is decreased with the increase of temperature or the decrease of strain rate.The flow stress curves exhibit the characteristics of strain softening obviously.Hot working instability region of AZ91 Dalloy exhibits the increasing tendency with increasing in deformation rate.At high temperature and high strain instability region,deformation instability is controlled by the adiabatic shear band and crack,while at low temperature and high strain instability region,un-even deformation and flow instability are attributed to the formation of partial shearing band at un-even dynamic recrystalization fine area.关键词：AZ91D Magnesium Alloy;Instability Region;Microstructural Evolution;Processing Maps
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发布时间：2023-12-18 - 摘要：The effects of rare-earth element Ce on the intergranular corrosion,corrosion depth and corrosion weight loss rate of A356 alloy were investigated by adding various content of Al-Ce master alloy into A356 alloys.The results reveal that the A356 alloy without Ce has severe intergranular corrosion.The addition of Al-Ce master alloy can improve the intergranular corrosion resistance of A356 alloy.With the increase of Al-Ce master alloy,the corrosion resistance of A356 alloy is increased firstly and then decreased.The A356 alloys with 0.1% Al-Ce master alloy has the least intergranular corrosion depth of42.5 !m and minimum weight loss rate of 0.786 5×10-4 g/（cm2·h）,respectively,showing the optimal intergranular corrosion resistance.关键词：Al-Ce Master Alloy;A356 Alloy;Intergranular Corrosion
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发布时间：2023-12-18 - 摘要：The Cu/Sn-0.7Cu/Cu solder joint was used as the initial sample to observe the evolution of interfacial IMCs with time under thermomigration.The growth of IMCs was observed and its dynamic parameters were presented.The results show that asymmetrical growth is present at the IMCs in two ends of the solder joint under thermomigration.The hot end is thinned and the cold end is thickened.The cold end forms holes in IMCs during thickening process.The growth of IMCs is the co-action of concentration gradient and thermomigration,which are concentrated to the growth of IMCs in the cold end and opposite effects in the hot end.Time index of growth kinetic is obtained by the thickness curve of Cu6Sn5,which is 0.55in cold end and-0.16in hot end.Finally,the migration flux of Cu atoms is calculated as1.37×10-7mol/（m2·s）.关键词：Cu/Sn-0.7Cu/Cu Solder Joint;Intermetallic Compounds;Growth Kinetic;Migration Flux
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发布时间：2023-12-18
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