材料期刊网

MICROSTRUCTURAL EVOLUTION AND CONTROL IN SUPERALLOY FORGINGS

R.Noel , D. Furrer , G. Shen and J. Lemsky(Ladish Co. , Inc. , P.O. Box 8902 , Cudahy , WI 53110-8902 , USA Manuscript received 26 Augnst 1996)

金属学报(英文版)

Optimum properties of high temperature superalloys are derived from interactions of the composition,thermomechanical deformation, and heat treatment.Nickel-base alloys contain a variety of alloying elements in a large number of combinations to produce various desired effects. The general characteristics of any specific nickelbase superalloy is determined by composition.The control of the microstructure in wrought processed superalloys can further influence the resultant component properties.The relationship between microstructure and properties is key in advanced design and manufacture of turbine engine components, and requires extensive alloy and process characterization to achieve desired results.Various forging methods have been developed and employed throughout the years to process superalloy components.Hammer forging, Press forging,and advanced isothermal press forging equipment and processes have been designed and manufactured to process speciality metals which often have very narrow processing windows.Combination processes have also been introduced into turbine engine applications,which result in a hybrid of resultant structures and properties.One such speciality,combination process is the Ladish Iso Con process which utilizes isothermal forging and conventional forging to achieve unique properties not matched by any other single process.Ladish utilizes forging presses for conventional forging, hot-die forging and for isothermal forging, in addition to hammers and ring rolling mills for wrought processing.This wide range of equipment allows flexibility in process design and optimization.Variations in temperature, strain and strain rate have been shown to significantly influence resultant grain sizes and microstructures.Tools are being developed to allow forging processes and specific forging parameters to be evaluated and optimized with regard to final microstructure before shop triale are required. Sophisticated finite element method (FEM) models are allowing the design of forging processes on computers rather than by iterative trial and error methods.

关键词: :forging , null , null

桥梁用钢示波冲击试验

杜丽影 , 邱保文 , 李荣锋 , 刘冬

物理测试

通过桥梁用钢示波冲击试验讨论了区分Wi、Wp与Wt的意义及其三者之间的关系,分析了试样的取样方向和试验温度对Wi、Wp与Wt值及其之间关系的影响.结果表明,L-T方向取样试样的Wt、Wp值均较大,Wi值变化没有规律性.Wp与Wt呈线性关系,不随试验温度和取样方向的改变而改变.Wt、Wp值随试验温度的降低而减小,Wi/Wt值随试验温度的降低而增加,均小于50％.

关键词: 桥梁用钢 , 冲击能量 , 裂纹形成能量 , 裂纹扩展能量

华南某垃圾焚烧厂排放PCBs和PCNs的固气分布、同系物分布及毒性当量特征

赵曦 , 李娟 , 陆克定 , 黄晓英

环境化学 doi:10.7524/j.issn.0254-6108.2015.07.2015020401

以华南某城市生活垃圾焚烧厂一期(WI-A)和二期(WI-B)为研究对象,采集了飞灰和烟气样品,通过GC/MS对其中PCBs和PCNs的全部单体进行了测定,分析了PCBs和PCNs的固气分布(飞灰和烟气中的总量比例)、同系物分布以及毒性当量特征.结果表明,WI-A和WI-B焚烧单位垃圾产生的PCBs和PCNs总量分别为0.397 mg·t-1(湿基)和0.363 mg·t-1(湿基).活性炭喷射量对PCBs的固气分布特征和去除率影响较大,对PCNs则不明显.PCBs同系物在烟气中以低氯取代单体为主,在飞灰中以高氯取代单体为主.PCNs同系物在烟气中以五氯单体为主,在飞灰中以四氯、五氯单体为主.WI-A和WI-B排放的烟气总TEQ分别为0.051 ng TEQ·Nm-3和0.096 ng TEQ·Nm-3,WI-A烟气Co-PCBs和D1-PCNs对总TEQ的贡献率分别为3.2％和0.13％,WI-B烟气Co-PCBs和D1-PCNs对总TEQ的贡献率分别为5.3％和0.34％,提示垃圾焚烧排放烟气中的Co-PCBs和Dl-PCNs的毒性同样值得关注.

关键词: 城市生活垃圾焚烧厂 , 多氯联苯 , 多氯萘 , 固气分布 , 同系物分布 , 毒性当量

Dependence of surface-compositional and angular distributions on the bulk composition in the sputtering of Cu-Pt and Cu-Ni alloys

Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms

Under 1 keV Ar ion bombardment of Cu-Pt and Cu-Ni alloys at high fluence at low temperature, the depletion degree of the segregating species at the second surface layer, and the normalized sputtering yield ratios (non-segregating species/segregating species) in the near-normal direction (15 degrees) and at oblique angles (75 degrees), have been estimated by an improved kinetic BIGS (Bombardment-Induced Gibbsian Segregation) model. For both the bombarded Cu-Pt and the bombarded Cu-Wi alloys, calculations show that the depletion degree of the segregating species at the second surface layer is small when its bulk composition equals the extreme value, but this depletion degree becomes large when its bulk composition equals the intermediate value. Furthermore, the difference of the normalized sputtering yield ratio between 15 degrees and 75 degrees is small when the bulk composition of the segregating species equals the extreme value, but this difference becomes large when that of the segregating species equals the intermediate value.

关键词: bombardment-induced segregation;ar ion-bombardment;gibbsian;segregation;enhanced diffusion;eutectic alloy;binary-alloys;temperature;elements;implantation;simulations

仪器化冲击法研究几种金属材料的冲击性能

陈庆垒

材料开发与应用 doi:10.3969/j.issn.1003-1545.2009.02.008

利用仪器化冲击试验机进行了D36、14MnVTiRe和10CrNiCu船体结构钢的系列冲击试验,结果表明:这几种船体结构钢具有较低的韧脆转变温度.用裂纹扩展功Wp作为韧脆转变温度的判据更加准确.韧脆转变前,断裂能量主要消耗于裂纹的扩展;韧脆转变后,裂纹形成功Wi明显大于裂纹扩展功Wp,断裂能量主要消耗于裂纹的形成.

关键词: 仪器化冲击 , 韧脆转变温度 , 裂纹形成功Wi , 裂纹扩展功Wp