最新刊期
卷 40 ， 期 2 ， 2020
- 摘要：The microstructure characteristics of the defect band in magnesium alloy castings during the cold-chamber high pressure die casting（HPDC）process was investigated,and the corresponding relationship between the defect band and the externally solidified crystals（ESCs）,porosity and process parameters was established,based on which the formation and evolution mechanism of the defect band was discribed.The results reveal that the microstructure at the cross section of magnesium alloy die castings can be divided by the defect band into three regions with obvious differences in microstructure characteristics compared with each other.With the increase of the slow shot plunger velocity,the area fraction of the ECSs in the microstructure of die cast magnesium alloy is decreased gradually,and the defect band becomes more clear and its location is closer to the center of die castings.The width of the defect band is reduced,and the porosity inside the defect band presents more concentration.With the increase of the fast shot plunger velocity,the ESCs become more dispersed,and the defect band is closer to the central region of die castings.When there is absence of fast shot,double defect band can be observed.The morphology and distribution of the defect band in the microstructure of die cast magnesium alloy is determined by the metal flow pattern during the filling process.Under the intensive flush and intensification pressure of melt flow,the grains in the contour of the metal liquid would be fragmented and rotated,resulting in a gap whose volume is larger than the volume of remaining liquid among grains.During the solidification process,the defect band with aggregated porosity can form following the contour of melt flow.关键词：Magnesium Alloy;Cold-chamber High Pressure Die Casting;Defect Band;Microstructure
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发布时间：2023-12-18 - 摘要：CNTs/AZ91D magnesium matrix nanocomposites were prepared by high-energy ultrasonic dispersion technology and metal mold gravity casting process.The solid solution T4 heat treatment and the aging T6 heat treatment were carried out for the composites prepared.The tensile strength and elongation of 1.0% CNTs/AZ91D composites with T4 treatment can reach 285 MPa and 17.3%,which are improved by 45% and 322%,respectively,compared with 196 MPa and 4.1% of the as-cast ones.After the aging T6 heat treatment,the tensile strength of the composites is further increased to 296 MPa,and the yield strength is increased significantly to 155 MPa,while the elongation is declined to 5.5%,showing obvious aging hardening effetcs.The microstructure of 1.0%CNTs/AZ91D composites was observed by metallographic microscope,scanning electron microscope and transmission electron microscope.The results reveal that carbon nanotubes can refine grain,promote slip and twinning and transfer load,so that the comprehensive mechanical properties of CNTs/AZ91 Dcomposites can be improved obviously.关键词：Magnesium Matrix Nanocomposites;Heat Treatment;Mechanical Properties;Microstructure
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发布时间：2023-12-18 - 摘要：<正>自2月底以来,法士特集团宝鸡厂日生产汽车变速器突破3 300台。标志着企业产能的全面恢复。据了解,在疫情持续向好的同时,法士特海内外市场持续回暖,目前,已接到出口订单超过1 500台。全体员工攻坚克难、奋力冲刺3月份月产10万台汽车变速器的产能高峰,为今年企业生产经营注入新动能。法士特董事长严鉴铂表示,在做好
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发布时间：2023-12-18 - 摘要：<正>2020年3月,烟台市举行重点招商项目网上集中签约,签约采用移动云视讯会议系统举行,其中云内动力发动机项目参与了此次签约。据了解,此次云内动力发动机项目,由云南云内动力集团股份有限公司投资建设,总投资5亿元,计划新上发动机生产、装配线2条,预计年产发动机20万台。资料显示,云内动力成立于1999年,位于昆明经济技术开发区,于1999年4月15日在深圳证券交易所上市,主要从事柴油机及机组,柴油发电机组;柴油机系列及
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发布时间：2023-12-18 - 摘要：<正>2020年3月19日,万丰集团旗下万丰飞机工业有限公司与全球最大的飞行培训学校中国民用航空飞行学院签署了战略合作协议。双方旨在飞机采购、适航支持以及产学研一体化等方面展开全方位的深入合作。万丰飞机工业系万丰奥特控股集团旗下的一家国际化企业。在全球拥有3个飞机制造基地（中国、奥地利、加拿大）、3个飞机设计研发中心（奥地利、加拿大、捷克）、1个在建飞机制造工程中心（中国）,在全球90多个国家设有190多个服务中心,是世界固定翼通用飞机制造前三强。
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发布时间：2023-12-18 - 摘要：<正>湖南省兴瑞精密制造有限公司年产8 000 t铝合金、锌合金压铸件改扩建项目环评公示显示,其投资的压铸改扩建项目位于汨罗高新技术产业开发区,主要从事铝铸件、锌合金铸件的生产。据了解,此次建设项目租赁湖南森科有色金属有限公司厂房,建筑面积2 532.25 m2。项目投资3 000万元,扩建投产后,可形成各类铸件800万件的生产能力。产品包括压缩机壳体、电机壳体、减速机壳体、减速机零件、烟花机零件、医药机零件、电机端盖、电机工具壳体、轴类零件、新能源汽车零件、钥匙机零件、行星齿轮箱体
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发布时间：2023-12-18 - 摘要：<正>据中商产业研究院数据库显示,2020年1-2月全国工业机器人产量波动有所下降,全国工业机器人产量为21 292套,同比下降19.4%。另外,2020年1?2月全国发动机产量下降明显,全国发动机产量为24 761.4万千瓦,同比下降38.8%。
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发布时间：2023-12-18 - 摘要：<正>福建省重点项目——寿宁三祥锆基非晶合金项目举行开工。项目由东莞宜安科技股份有限公司与三祥新材股份有限公司合资建设,总投资6亿元,分3期建设。2020年3月6日,双方签署协议合资设立宁德三祥液态金属科技有限公司,合作投资锆基非晶合金（液态金属）项目。
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发布时间：2023-12-18 - 摘要：The effects of Sr and Ti on microstructure and properties of the die-casting rare earth modified AZ91 magnesium alloy were investigated.Through compared with that of AZ91 alloy,the strength of AZ91+RE alloy is increased with the decrease of elongation.After further adding Sr,plasticity of the alloy is improved due to refinement effect,while the strength and corrosion resistance of the modified alloy are decreased.The addition of Ti can inhibit the adverse effect of Sr and remain good plasticity.The AZ91+RE+Sr+Ti alloy has the desirable comprehensive properties by multi-element microalloying.The evolution of microstructure with the addition of components is responsible for the change of material properties.关键词：RE Magnesium Alloy;Microstructure;Mechanical Properties;Corrosion Properties
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发布时间：2023-12-18 - 摘要：Four groups of samples,including base metal（BM）,FSW,FSW+T and FSW+T+A samples,were designed to investigate the effects of plastic deformation on the corrosion resistance of the joints immersed in 3.5% NaCl solution.The results reveal that the corrosion resistance of AZ31 magnesium alloy can be enhanced significantly by friction stir welding,while post-welded tension can weaken significantly the corrosion resistance of the joint,however post-annealing treatment can enhance largely the corrosion resistance.Corrosion rate of the four groups of samples is presented as follows:BM>FSW+T>FSW≈FSW+T+A.In addition,both extension twinning and dislocation slip introduced by post-welded tension have an adverse effect on the corrosion resistance of the joint,in which dislocation slip plays the key role.关键词：Friction Stir Welding;Magnesium Alloy;Corrosion Resistance;Dislocation Slip
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发布时间：2023-12-18 - 摘要：The strength of resin sand has a significant influence on the quality of castings.Many factors can affect the strength of resin sand,especially the sand size and resin content.Effects of different furan resin addition and sand sizes on furan resin sand were investigated through analyzing strength of specimens and hardening and crack mechanism of furan resin sand with the help of SEM analysis.The results reveal that the microscopic pore in the binding bridge has a significant effect on the strength of furan resin sand.With 1.25%to 1.75%of resin content,a satisfied strength of sand can be obtained.The sand size has an effect on the strength of binding bridge,and a small size of grain leads to the adhesive fracture between binding bridge and sand particles,which can decrease the strength of furan resin sand.关键词：Furan Resin Sand;Strength;Grain Size;Binding Bridge
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发布时间：2023-12-18 - 摘要：The relationship between flow stress and strain rate,deformation temperature and strain was investigated during the plastic forming process of AZ40 Malloy through hot-compressive simulation testing.The FieldsBackofen model was established by experimentally obtained true stress-true strain data,and the optimization and improvement were carried out to put forward a new model.Meanwhile,the processing map of AZ40 Malloy was drawn.The results reveal that the Fields-Backofen model prediction curve of AZ40 Malloy is well in agreement with the experimental data before peak stress.The modified new model has a higher precision,where the correlation coefficient reaches 0.991 8 and the average relative error is 3.84%,and the prediction curve of the whole deformation stage is in better agreement with the experimental data.The processing map analysis shows that the hot working of the alloy is more suitable in the range of deformation temperature of 620～673 Kand strain rate o f0.005～0.05 s-1.关键词：AZ40M Alloy;Hot Compression;Flow Stress;Fields-Backofen Model;Processing Map
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发布时间：2023-12-18 - 摘要：Non-equilibrium solidification and precipitation behavior of rapidly cooled K424 alloy were analyzed by copper mould spray casting combined with isothermal annealing.The results reveal that microstructure is refined greatly in spray-casted alloy,and secondary dendrite spacing is reduced greatly in comparison with that of as-cast one.Moreover,the relief of solute segregation is beneficial to suppress the formation of coarse carbide and eutectic structure.With the decrease of inner diameter,the dendrite morphology in the K424 alloy is changed from random equiaxed grain to preferred growth of directional mode.After isothermal annealing between 800～1 000℃ for 30 min,γ′phase is precipitated in non-equilibrium solidified alloy,and its size and volumetric fraction are increased with increasing in aging temperature.Because of the formation of considerable uniform and fine sphericalγ′phase,microhardness of 478 HV can be obtained after holding at 900℃for 30 min,which is 13%higher than that of the initial rapid cooled alloy.关键词：Non-equilibrium Solidification;Microstructure Refinement;Precipitation;Superalloy
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发布时间：2023-12-18 - 摘要：<正>新冠肺炎疫情此前在国内肆虐时,因国内零部件短缺,海外车企的生产供应曾一度受到影响。如今,新冠肺炎疫情波及全球,更是给欧洲和北美两大汽车产业中心地区蒙上阴影。据不完全统计,包括戴姆勒、大众、菲亚特克莱斯勒集团（FCA）、标致雪铁龙集团（PSA）等在内的12家海外车企已经关停或计划关停的工厂将超过100家。目前欧洲地区受波及影响最重,已经关停的工厂将超过90家,受此次疫情影响,2020年2月欧盟乘用车市场注册量同比下降7.4%,至957 052辆,欧洲汽车销量创下自
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发布时间：2023-12-18 - 摘要：<正>市场调研机构Strategy Anaylytics发布数据,2020年2月份,全球智能手机出货量为6 200万部,同比下滑38%,环比下滑39%。究其原因,主要是新冠疫情的爆发和季节性因素对智能手机行业造成冲击,几乎所有智能手机厂商都受到了影响,中国内地市场受冲击尤为严重。这是自智能手机市场开始有统计数据后最严重的一次下滑。分析人士指出,尽管中国开始显示出复苏的迹象,但3月份
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发布时间：2023-12-18 - 摘要：The research progress in rare earth modification of A356 alloy was reviewed.The modification effects of various RE elements on A356 alloy were reviewed.Combined with commercial application of A356 alloy,the method of relatively cheap binary,even multi-component rare earth or rare earth complex modification systems with other elements is a promising and practical direction by DOE composition design.关键词：A356 Alloys;Rare Earth Element;Modification
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发布时间：2023-12-18 - 摘要：The development of TiAl alloy was reviewed.Aiming at the problems in composition uniformity and cracking in the preparation of TiAl alloy ingots,it is analyzed for the process control,process improvement and new technologies for melting,and the measures to solve the problems were put forward.关键词：TiAl Alloys;Vacuum Consumable Arc Melting;Ingot;Composition Uniformity;Crack
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发布时间：2023-12-18 - 摘要：Compared with those in the gravity cast AlSi10Mg alloy,fine crystal grains are generated in the alloy during the laser selective melting forming process,and the coarse or needle-like Si phase in theα-Al matrix becomes mesh-like with uniform distribution.Due to the rapid cooling rate during the laser forming process,the supersaturated solid solution is formed,and the tensile strength,yield strength and elongation of the alloy reach 483 MPa,314 MPa and 6.43%,respectively.After T6 treatment,the uniform network-like Si phase is dissolved and broken to grow the irregularly shaped Si phase and the finely dispersed Si phase which are rounded and passivated,and the tensile strength and yield strength of the alloy are reduced to 208 MPa and 167 MPa,while the elongation is improved to 10.37%.关键词：AlSi10Mg Alloy;Selective Laser Melting;Heat Treatment;Microstructures;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The numerical simulation was adopted to simulate the process of blowing gas into converter slag before slag splashing protection by a software.The influence of molten pool depth and slag viscosity on the flow of the molten pool was analyzed.The simulated results show that the deepening of the molten pool is conducive to the enhancement of turbulent kinetic energy conversion rate and the homogenization of the molten pool,and to the optimization of the flow field.The slag viscosity has a great influence on the dead zone ratio.The dead zone ratio is increased with the increase of the slag viscosity.Therefore,it is necessary to increase the injection time to make the molten pool stable and uniform in the deep melting pool with high viscosity.关键词：Converter Bottom Blowing;Numerical Simulation;Pool Depth;Viscosity
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发布时间：2023-12-18 - 摘要：In order to compound refinement of primary Si and modification of eutectic Si,the Al-22 Si-Cu alloy was investigated which was prepared by the combined process using a water-cooled copper serpentine pouring channel（SPC）and Sr-modifier.The results indicate that the grain size of primary Si is refined from 90μm to 28.03μm by the serpentine pouring channel process.With increasing in the Sr content,the precipitation temperature of primary silicon is decreased,and the twin density and grain size of primary Si are both increased firstly and then decreased,which reach the maximum value with the addition of 0.09%Sr.The eutectic Si morphology is modified from acicular to fibrous.The tensile strength of the Al-22 Si-Cu alloy with the addition of 0.12%Sr reaches 212.32 MPa.关键词：Al-22Si-Cu Alloy;Serpentine Channel;Primary Si;Eutectic Si;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Aiming at problems in spatial confinement of die structure in conventional super-point cooling,a new super-point cooling was presented to enlarge the using range of point cooling and eliminate burning,shrinkage holes in partial narrow position in die castings,so the qualified rate of die castings was improved greatly.关键词：Super-point Cooling;Thermal Balance;Die Casting
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发布时间：2023-12-18 - 摘要：The microstructure,mechanical properties under different solid solution and aging conditions and internal defects of the squeeze casting A365.2 aluminum alloy engine mount bracket were investigated.The results reveal that microstructure of the heat-treated A356.2 alloy is composed mainly ofα-Al matrix,eutectic Si phase and Mg2Si phase with a grain size of about 148μm and the secondary dendrite spacing around 20μm.After solution aging treatment,part of the eutectic Si phase is dissolved into theα-Al matrix,and the other is distributed in the form of granular or spherical particle at theα-Al grain boundary.The solution time,aging temperature and aging time can affect the mechanical properties of A356.2.It is found that with solution at 535 ℃ for 6 hand water quenching for 8 min+ aging at 170℃for 6 h,the tensile strength,yield strength and elongation of the squeezing casting aluminum alloy bracket reach 340.5 MPa,274.5 MPa and 10%,respectively,meeting the mechanical properties standard required by the engine bracket.关键词：Squeeze Casting;Engine Mount Bracket;Solution and Aging;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Based on the high precision feature of the waveguide tuber for phased array radar,the die-casting and assembly technology were adopted to manufacture the waveguide tube meeting the technological requirement.Through analyzing the process difficulties of the waveguide tube,the gas-controlling method of YL113 aluminum alloy,die-casting technique and assembly technology were analyzed.The results show that by using inert gas refining and vacuum degassing process,the gas content in the liqurd Al is decreased significantly which is better for the internal quality,By optimizing the pouring gate design and processing parameter,the dimensional precision of the loudspeaker-like casting and two stiffened reinforcing rib can be guaranteed with yield strength more than 270 MPa and elongation more than 2%.Meanwhile,using annealing,natural aging treatment and assembly fixture,the dimensional precision of the waveguide tube can be guaranteed and the product qualified rate can be reached up to 91%.关键词：YL113 Alloy;Hydrogen Content;Die Casting;Assembly;Dimensional Precision
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发布时间：2023-12-18 - 摘要：Different refractory fillers were added to the gypsum,and the flowability,time,wet strength of gypsum powder,strength after calcination,linear shrinkage and microstructure of the gypsum slurry were tested and analyzed at the same water-paste ratio.The results reveal that coal gangue and diatomaceous earth are simultaneously incorporated into the gypsum cast powder,then,after calcination the gypsum grains are well overlapped,compacted and the gypsum molding have the good strength.The flow diameter of gypsum slurry is 90 mm,the initial time of 7 min with the final time of 17 min,the flexural strength of 2.02 MPa,the compressive strength of2.3 MPa.After calcination the flexural strength is 0.458 MPa with the compressive strength of 1.07 MPa,and its linear shrinkage rate of 0.320% when the content of coal gangue is 20%and diatomite is 10%.关键词：Coal Gangue;Diatomaceous Earth;Investment Gypsum Type;Fluidity;Strength;Linear Shrinkage
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发布时间：2023-12-18 - 摘要：The temperature field distribution of the guide vane of heavy-duty gas turbine was analyzed by combining with precision casting experiment and numerical calculation.In addition,the forming process of shrinkage porosities was expounded by semi-quantitative theoretical calculation.The results reveal that the shrinkage porosities are closely related to the shrinkage volume in solidification stage,and the shrinkage volume is closely related to temperature gradient,wall thickness and mushy-zone width.Through increasing the temperature gradient in all directions,the shrinkage volume can be reduced to be eliminated.Meanwhile,it can also slow down the overheating of the casting on the core and shell side.关键词：Gas Turbine Guide Vane;Shrinkage Porosities;Formation Mechanism;Temperature Gradient
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发布时间：2023-12-18 - 摘要：It was described for formation mechanism of the pores in the castings,the test methodes of the permeability of the coating and the factors affecting the permeability of the coating.The research progress of gas hole defects in lost foam castings was summarized in recent years.The principle of gas permeability testing of several coatings at present was expounded.The effects of coating thickness,refractory particles and organic additives on the permeability of coatings were analyzed.关键词：Lost Foam Coating;Porosity Defect;Gas Permeability Testing;Coating Thickness;Refractory Aggregate
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发布时间：2023-12-18 - 摘要：The casting behavior of copper cladding aluminum in the horizontal continuous casting process was investigated.The effects of pouring temperature of liquid aluminum and casting speed on the distribution of temperature field,liquid fraction and velocity field for copper cladding aluminum during continuous casting process was numerically analyzed using the Fluent TMsoftware combining with the experiments.The simulated results show that with the increase of the pouring temperature of aluminum melt in the graphite core,the temperature of aluminum melt contacted with the copper tube is increased,and the melt meniscus depth is increased,so the reaction between aluminum and copper is generated easily.In addition,with increasing in the casting speed,melt meniscus depth of aluminum liquid is increased,and the contact time between liquid aluminum and the copper tube wall is increased.The simulated results are in good agreement with experimental ones.The experimental results show that the high quality ingot can be obtained at the pouring temperature of 710～730 ℃and casting speed of 200 mm/min.关键词：Copper Cladding Aluminum;Composite Materials;Horizontal Continuous Casting;Numerical Simulation
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发布时间：2023-12-18 - 摘要：Three-dimensional orthogonal Cf/Al composites with volume fraction of 50% Cfwere fabricated by vacuum pressure infiltration.The microstructure and bending properties of the composites at room temperature and high temperature were investigated.The failure mechanism of bending properties of the composites was described.The results indicate that the micro-void defects in the warp microstructure of three dimensional orthogonal Cf/Al composites are slightly more than those in the weft microstructure.The bending strength of the composites at room temperature、350℃and 400 ℃ reaches 498.8 MPa、363.0 MPa and 303.0 MPa,respectively.The bending modulus of the composites at room temperature、350℃ and 400℃ reaches 70.8 GPa、63.7 GPa and 65.6 GPa,respectively.The bending failure is mainly attributed to the buckling deformation of the warp fiber bundles caused by the compression on the inner surface,and the morphology of weft fiber bundles is relatively intact.In addition,the tensile failure of the composites is caused by the tension of the external side and existence of fiber pull-out.关键词：Three Dimensional Orthogonal;Cf/Al Composites;Microstructure;Bending Behavior
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发布时间：2023-12-18 - 摘要：SiCp/Al-Fe-V-Si composites were prepared by spray deposition,and then were wedge pressed.The effects of wedge pressing on pores,density,SiC-Al interface and mechanical properties of the composites prepared were investigated.The results reveal that microstructure and properties of the composites prepared can be improved effectively by increasing the cumulative reduction of the wedge pressing.The pressed blank is characterized with weak metallurgical bonding,low ultimate strength and elongation because of microcracks among deposited particles and between SiC particles and the Al-matrix when the cumulative reduction is lower than 45%.With cumulative reduction more than 45%,the micro-crack among the deposited particles as well as between Al matrix and SiC particles is bridged,so interface bonding is improved.Meanwhile,there is absence of evident Al4C3 brittle phase generating.There is no significant change in microstructure of the composite when the cumulative reduction is more increase,while the SiC particles are distributed more uniformly.The ultimate strength and elongation of the composites reach 291 MPa and 2.4%,respectively,when the cumulative reduction is 50%.关键词：Aluminum Matrix Composite;Wedge Pressing;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The（Mg2Ni+Mg3Sb2）/Mg composites with different Ni content were prepared by powder metallurgy method,and the prepared composites were deformed by hot pressing process.The effects of hot pressing on the microstructure and mechanical properties of（Mg2Ni+Mg3Sb2）/Mg composites were investigated.The results reveal that the hot press deformation can refine the matrix Mg particles,and improve the uniformity of Mg3Sb2 and Mg2Ni microstructure distribution as well as eliminating the defects such as voids and cracks in the composites and improving the density,so significantly increasing the mechanical properties of the composites.关键词：Powder Metallurgy;Hot Pressing Deformation;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：<正>中国铸造协会日前发表声明称将原定于5月召开的2020年上海会展活动延期至8月。目前,国内疫情持续向好,国家会展中心也已具备办展条件,但随着疫情全球蔓延,国际防控形势变得尤为严峻。为积极响应国家号召,优先支持企业全面实现复工复产,同时为保证展商和观众的安全健康,减小疫情对展会效果的影响,中国铸造协会经综合评估后慎重决定,原定于2020年5月13-16日于上海
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发布时间：2023-12-18 - 摘要：The effects of trace rare earth cerium on as-cast structure of industrial pure aluminium were investiagted.The refinement and modification mechanism of cerium on microstructure were analyzed.The results show that trace cerium can increase the perturbation of supercooling and solute instability,and release a large amount of latent heat,which lead to the decrease of interface stability and the refinement of microstructure and grain size.Cerium has a higher chemical activity,so it is easy to generate newαphase core and promote grain refinement.The rare earth compounds formed on the interface will fill the defects on the interface surface to promote the transformation of the impurity phase into pellets,and adsorb the impurity atoms to enrich at the grain boundary.关键词：Rare Earth;Aluminium Cable Steel Reinforced;Grain Refinement;Modification Mechanism
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发布时间：2023-12-18 - 摘要：The effects of strain rate on the plastic deformation mechanism of magnesium twin interface with void were investigated by molecular dynamics simulation with embedded atomic potential.The results reveal that the main forms of plastic deformation include partial dislocation,slip band and stacking fault.The Young’s modulus is independent of strain rate,and with the increase of the strain rate,the yield stress is increased.With the strain rate increase,the number of dislocations and slip bands are increased,while the number of stacking faults is increased firstly and then decreased,meanwhile the average length of dislocation motion free travel is decreased.With the deformation applied,the dislocation source produces new dislocations continuously,which leads to the increase of dislocation density.With high strain rate,stress concentration is easy to form at grain boundary,and microcracks will occur.关键词：Molecular Dynamics;Twin Interface;Void;Partial Dislocations
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发布时间：2023-12-18 - 摘要：The casting process of complex Zl114 Aalloy housing was analyzed from the housing design,casting process design,internal quality control,mechanical property control and size control.Combined with the numerical simulation technology,the developed time of casting is shortened,and the premium housing with internal quality、mechanical properties and size accuracy can meet the design requirements.关键词：ZL114A Castings;Casting Process;Design
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发布时间：2023-12-18 - 摘要：The as-cast Ti-48Al-2Nb-2Cr alloy was subjected to high temperature hot compressive deformation test by using Gleeble-1500 thermal simulator at 1 050℃to 1 200℃and the strain rate of 0.001 s-1 to 0.1 s-1 as well as deformation rate of 60%.The relationship between deformation temperature,strain rate and flow stress during high temperature deformation of the alloy was analyzed.Meanwhile,the active energy of the alloy was calculated.The Arrhenius constitutive model of Ti-48Al-2Nb-2Cr alloy and the constitutive model of multiple linear regression were established.The results reveal that the active energy of the alloy is increased with increasing in temperature and strain rate.The correlation coefficient Rof the Arrhenius constitutive model reaches 0.982 28,and the average relative error is 9.97%.In addition,the relative error within 10% only accounts for 62.0%.The correlation coefficient Rof the constitutive model of Ti-48Al-2Nb-2Cr alloy with multivariate linear regression reaches0.995 66,and the average relative error is 4.76%,meanwhile,the relative error within 10%is 92.6%,presenting a higher constitutive accuracy.关键词：Ti-48Al-2Nb-2Cr Alloy;High Temperature Deformation;Active Energy;Constitutive Model
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发布时间：2023-12-18
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