稳定化退火温度对Al-6Mg-0.3Mn-0.13Sc-0.13Zr合金板材组织和性能的影响

试验研究了不同稳定化退火温度对Al-6Mg-0. 3Mn-0. 13Sc-0. 13Zr合金冷轧板材组织和性能的影响。试验研究结果表明:随稳定化退火温度的升高,板材强度下降而塑性升高,腐蚀抗力则先升而后降;合金板材经350℃稳定化退火1h可达到强度、塑性和耐蚀性的最佳配合。     

稳定化退火对大生产条件下制备的5B70铝合金板材组织和性能的影响

采用半连续铸造,轧制技术制备了5B70铝合金冷轧板材,板材规格为2 mm×1 200 mm×2 000 mm.研究了稳定化处理工艺对该合金冷轧板材力学性能、腐蚀性能、电导率和显微组织的影响.结果表明,随稳定化退火温度的升高,冷轧板材强度呈下降趋势,塑性呈上升趋势,电导率先升而后降,冷轧板材腐蚀速率则先降而后升,200℃1 h稳定化退火后腐蚀速率最大;合金板材经320℃1 h稳定化退火可达到强度、塑性和耐蚀性的最佳配合.     

Sc含量对Al-Mg-Mn合金板材组织与性能的影响

采用半连续铸造-轧制技术制备了两种Sc质量分数含量为0.25%和0.10%的Al-Mg-Mn合金薄板,研究了稳定化退火工艺对两种不同Sc含量合金板材拉伸力学性能、剥落腐蚀性能和显微组织的影响。结果表明,两种合金冷轧板材稳定化退火过程中有相同的组织、性能变化规律,即随着退火温度升高,板材强度稍有下降而塑性升高,表现出很强的抗退火软化的能力,其中低Sc含量合金拉伸性能略低于高Sc含量合金的;其次,随退火温度的升高,板材抗剥落腐蚀的能力也表现出相同规律性的变化,200℃1 h左右退火时剥落腐蚀最严重,随着退火温度升高,抗腐蚀性能提高;两种合金冷轧板材在300℃1 h稳定化退火可以获得较好的综合拉伸力学性能和腐蚀性能,在此条件下,低Sc含量的合金板材抗拉强度、屈服强度和伸长率仍然分别达到437 N/mm2、340 N/mm2和16.3%,有很好的开发应用前景。     

稳定化退火对5B01合金性能和织构转变的影响

采用半连续铸造-轧制技术制备了5B01合金板材.研究了稳定化退火工艺对冷轧板材力学性能、抗剥落腐蚀性能以及织构的影响.结果表明,随稳定化退火温度的升高,5B01冷轧板强度呈现下降趋势而塑性升高,抗剥落腐蚀能力则先升后降.冷轧板材中主要存在黄铜织构{011}(211),铜织构{112}(111)和S织构{123}<634>,当退火温度升高到300℃左右时,板材的形变织构逐渐消失,分别向立方职构{001}(100)以及旋转立方织构{001}(110)转变.     

退火工艺对Al6MgSc合金力学性能与剥落腐蚀性能的影响

采用力学性能测试、目视剥落腐蚀试验、极化曲线和交流阻抗测试等试验方法，研究了Al6MgSc合金在不同中间退火和稳定化退火后的力学性能和剥落腐蚀性能。结果表明：中间退火对该合金的力学性能基本没有影响，在340℃中间退火时的抗剥落腐蚀性能最好；而稳定化退火温度升高使合金强度下降，在250℃退火时的抗剥落腐蚀能力最强，极化曲线和交流阻抗的测试结果与剥落腐蚀的测试结果相符合。     

冷变形工艺对铝-镁-钪合金性能的影响

采用半连续铸造方法制备了铝-镁-钪合金2.0 mm×1 200 mm×2 000 mm板材,研究了冷变形工艺对冷轧板组织和性能的影响。结果表明,铝-镁-钪合金随冷变形量增加强度升高,塑性下降。采用热轧后温轧或中间退火后冷轧,再在一定温度下进行稳定化退火的工艺,可以获得综合性能良好的铝-镁-钪合金冷轧板材。     

稳定化退火制度对Al-4.5Mg-0.7Mn-0.2Er合金板材组织和性能的影响

试验研究不同稳定化退火制度对Al-4.5Mg-0.7Mn-0.2Er合金冷轧板材组织和性能的影响。结果表明:冷轧板材在290℃退火,随着退火时间增加板材的强度逐渐降低、塑性逐渐增大;随着退火时间增加,板材的晶间腐蚀失重值逐渐减少;板材在290℃,保温45 min退火,其强度、塑性和耐蚀性为最佳。     

TC25合金板材的热处理工艺

研究了不同热处理工艺对TC25合金板材力学性能的影响。结果表明,普通退火的塑性高于双重退火。随着普通退火温度的升高,TC25合金板材的强度呈缓慢上升趋势,塑性先升高后降低。随着冷却速度的提高,塑性明显增大,抗拉强度略有升高,屈服强度显著下降。采用900℃×1 h,水冷的热处理工艺可以确保TC25合金板材的强度、塑性匹配最佳。     

退火工艺对MHC钼合金板材组织和力学性能的影响

采用粉末冶金工艺制备了MHC钼合金板材,通过拉伸力学性能测试、硬度测试、金相分析等测试手段,研究了退火温度对MHC钼合金板材显微组织和力学性能的影响。结果表明:轧制后的MHC钼合金板材的纵向抗拉强度为1150 MPa,规定塑性延伸强度为1020 MPa,伸长率为10.5%,维氏硬度为352 HV10。MHC钼合金板材在1400℃开始发生再结晶,到1700℃发生了完全再结晶,其抗拉强度和硬度均随退火温度的升高而降低,在1300~1500℃范围内伸长率随退火温度的升高而升高,在1500~1700℃范围内伸长率随温度的升高而降低,在1500℃的伸长率最高,达到22.5%。     

变形量及热处理对TA7合金板材组织性能的影响

研究了TA7合金板材在不同热处理温度、不同变形量时的组织、力学性能的变化。结果表明:TA7合金在700~850℃随退火温度升高,强度明显降低,塑性上升;相同热处理温度下,TA7合金随变形量增加,再结晶程度增强,加强度降低,而塑性升高。     

Features of formation of the structure in production of blanks of disks of heat-resistant nickel alloys

Conclusions To provide a high level of mechanical properties in wrought blanks of cast ÉP741NP and ÉP962 alloys it is necessary to form controlled structures. A necklace-type structure formed in homogenizing isostatic treatment, subsequent thermomechanical working including alternation of the operations of deformation in the (+)-area and recrystallization anneals, and final heat treatment is preferable. The temperature conditions of all stages of thermomechanical working are strictly controlled, especially the final operation of deformation and heating for hardening. To eliminate hardening cracks and distortions it is necessary to use molten salts at t=600°C as quenchants. The use of multiple production operations makes it possible to significantly reduce the structural inhomogeneity related to inhertance of the original dendritic structure. However, the structure of the final semifinished product is nevertheless characterized by a difference in occurrence of the processes of polygonization and recrystallization between the former dendritic cells and the interdendritic spaces in deformation and heat treatment.To obtain structurally homogeneous blanks for gas turbine engine parts it is necessary to use basically new methods of remelting such as vacuum double electrode remelting and electron beam remelting with an intermediate vessel.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 25–29, December, 1991.     

Ab-initio calculation of enthalpies of formation of intermetallic compounds and enthalpies of mixing of solid solutions

A large number of ab-initio calculations of energies of formation of intermetallic compounds have been performed in the last 15 years. The currently used methods are listed. The paper presents a review of the aluminium based compounds which have been studied. Comparisons of calculated and experimental enthalpies of formation are provided for aluminim-3d and-4d transition metal alloys at equiatomic composition. The modelling of the enthalpies of mixing of solid solutions based on a given lattice is described.     

试论洋务派教师聘任的思想

洋务派在洋务学堂的办学活动中,为了解决西学专业学科的教学困难,采用了聘请外籍教师的应急措施.他们以真才实学,合同制管理作为主导思想,并认为这种解决师资的途径只是权宜之计,并非久远.从客观上看,洋务派的教师聘任思想有深刻的历史影响.     

Prospects of the Use of Synergetic Approach to Solution of Problems of the Science of Nanomaterials

A synergetic approach to solution of problems of self-controlled synthesis of nanostructures and creation of self-organizing nanotechnologies is considered in connection with the superproblem of creation of materials with functional properties resembling those of biosystems. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 55 – 61, July, 2005.     

Kinetics of the oxidation of metals — Influence of self-diffusion of metal

The importance of the self-diffusion of a metal during its oxidation by a gas is treated for the cases of nonstoichiometric oxides having either interstitial cation or cation vacancies. We have established a general relationship for the reaction rate when a mixed diffusion process occurs. From this relationship, we have shown that the pressure dependence can be different, according to whether the rate-determining process is the self-diffusion through the metal or through the product.     

FeCrAIW电弧喷涂层组织的致密化研究

采用激光辐照对FeCrAlW电弧喷涂层的组织进行致密化处理,借助扫描电镜和X衍射对涂层的组织进行了分析.测试了涂层的显微硬度.结果表明:涂层组织致密度提高,孔隙率明显降低.随着激光扫描速度的增加,涂层的显微硬度降低.在较低的扫描速度下,涂层与基体之间形成互熔区,涂层与基体之间产生良好的冶金结合.     

面向零件形状的计算机图形库的开发

论述了CAD技术中参数化设计的三种建模方法，重点介绍了基于特征的参数化建模原理。在此基础上，分析机械设计中的机构结构，归纳出其零件的几何特征构成。设计了机构CAD图形库，并提出了该图形库生成步骤和人机交互界面。